Month: December 2017

Micro Irrigation: How to Make Every Drop Count

Evan 18 Comments

 

Mike Wissemann is a tenth generation farmer from Sunderland, MA. His farm, Warner Farm, has been an established source of crops for the surrounding towns since 1718. Mr. Wisseman inherited three hundred years of farming techniques and tricks. He spent his high school years working on the family farm and went on to receive a degree in Plant and Soil Science from the University of Massachusetts Amherst. Mr. Wisseman successfully expanded the farm and his crops from potato/onion crop to a wide variety of fruits and vegetables (Schwarzenbach, 2017). However, no amount of experience or education stopped him from losing tens of thousands of dollars when the Northeast experienced one of its worst droughts in decades (Kaufman, 2016). Farmers all over the Northeast were left scrambling to find enough water for their crops–some were even reduced to bucket brigades to get enough water to their acres of farmland (Shea, 2016).

Despite their best efforts, farmers could not plant their second round of crops. Even generally fertile farm areas such as those by rivers had major problems trying to irrigate (Schwarzenbach, 2017). When your entire livelihood depends on a natural resources (such as water), climate change and increasing drought years are a direct danger to your livelihood.

As climate change continues, droughts like the one experienced by Mr. Wissemann, are going to become more common.  Rising temperatures associated with climate change have impacted approximately 80% of monthly heat records (Coumou, Robinson, & Rahmstorf, 2013). As a rule, as temperature increases, the rate at which an organism produces energy increases as well (Hansen, Smith, & Criddle, 1998). This would be beneficial to productivity, if increased temperatures did not have the additional effect of decreasing the amounts of water available in soil. Think about the application of heat to a pot of water; when the water boils, the water escapes the pot in the form of vapor into the air. The same process holds true when heat is applied to the ground; the water escapes the soil in the form of vapor. This process leaves the soil devoid of water for the plants and leads to drought. The U.S. is a top exporter of agricultural goods and climate change is going to have a significant impact on our agriculture (Joint Economic Committee Democratic Staff, 2012). Between 2000 and 2015, 20-70% of the United States experienced abnormally dry conditions each year (Environmental Protection Agency [EPA], 2016). This does not bode well for the agricultural industry as droughts have an intensely negative impact on crops.

Decreased soil moisture means less water is available for the plants. This both leads to water stress and exacerbates heat stress. Water stress is a variety of plant symptoms that negatively affect plant productivity. It also aggravates heat stress which is when a plant suffers significant tissue damage because of high temperatures or high soil temperatures (Hall, 2017). The same way that humans expect to catch a cold from being overly cold or hungry for too long, plants are more susceptible to disease after being dehydrated and overheated for too long. When leaves of corn are subjected to drought-like conditions, they contained 69% more diseased biomass (Vaughan et al., 2016). When a plant is dehydrated, tiny openings in the leaves close to avoid further loss of water through evaporation. When these openings close, the leaf is incapable of expelling oxygen and taking in carbon dioxide–as if the plant is holding its breath (Osakabe, Osakabe, Shinozaki, & Tran, 2014). Increased heat stress and decreased water availability reduces the plant ability to breathe and thus make food. This results in a weakened plant that is more susceptible to disease (Irmak, 2016; Vaughan et al., 2016).

To get a better sense of the effects of combining heat and water stress, these processes can be related to the human body. Heat stress is similar to running; it elevates your heart rate.  If you run forever without rest, you will pass out, and most likely die without medical attention. Water stress, which is like holding your breath, will also eventually kill you, but can be done for some length of time. When heat stress and water stress occur simultaneously, it is like running a marathon while holding your breath. Such a venture would result in near-immediate loss of consciousness, and death without medical attention. Similarly, a plant under both water and heat stress, sees a drastic decrease in productivity, and eventual death without a change in conditions.

We are exceptionally vulnerable to these effects of climate change on our crops due to our current method of water usage. Current estimates reveal that 70% of freshwater withdrawals go towards irrigation uses (Block, 2017) and a large amount of this water could be conserved. A widely accepted, but inefficient method of irrigation is furrow or gravity irrigation. It accounts for 35% to 42% of irrigation systems in the United States (Subbs, 2016). Compared to a more modern technique known as drip irrigation, it wastes 43.6 % of total water use (Tagar et al., 2012,  p. 792). Furrow irrigation involves planting crops in rows with small trenches running in between them. Water is then flown down the trenches that run alongside the crops (Perlman, 2016). Farmers across the nation use furrow irrigation because there are lower initial investment costs as well as a lower cost for pumping water (Yonts, Eisenhauer, & Varner, 2007). Unfortunately, it also wastes a lot of water. The water is not targeted on the roots and much of it goes to wetting soil around the plant and not the actual root. This is inefficient because the roots are the plant structure that absorb the water (Lamont, Orzolek, Harper, Kime, & Jarrett, 2017). The water that is not on the roots is more likely to be lost as soil evaporation which accounts for over 50% water lost in furrow irrigation (Batchelor, Lovell, & Murata, 1996). Traditional forms of irrigation irrigate the entire field, wasting precious water on soil that will not be in contact with the plant’s roots (Lamont et al., 2017).

Plants need fresh water to survive but, unfortunately, water is a finite resource. Although the water covers 70% of the planet, only 2.5% of it is fresh water. This freshwater is “stored” in places like rivers, lakes, ice, and, perhaps most importantly, in the ground. Surface water seeps down through layers of dirt and rock to recharge groundwater storage areas, more commonly known as aquifers. Aquifers are made up of types of rock particles, such as sand and gravel,  that have enough space between them that the water can happily live. We need freshwater for activities ranging from drinking to manufacturing processes to agricultural irrigation. And about 50% of the freshwater we use for these activities is derived from groundwater (Dimick, 2014).  

The main differing factor between groundwater and surface water as a source of fresh water is the time it takes for these reserves to be recharged. Surface waters, such as lakes, can be replenished with seasonal rains. Groundwater on the other hand can take anywhere from months to tens of thousands of years to build up a reserve because the water has to flow through layers and layers of soil and rock to reach the aquifer. It can also be left untouched for long periods of time as it is not susceptible to the same rules of constant evaporation as surface water.

Agriculture has been using up this resource far faster than it can be replaced. It may take years to build up a water reserve, but it only takes seconds to pump it out. For example, the Ogallala Aquifer, which is located under the Great Plains of the United States, recharges at a rate of less than 1 inch per year (Kromm, 2017). However, over the past decade water has been withdrawn at a rate of approximately 18 inches per year. It is estimated that in the next 50 years, 69% of the Ogallala Aquifer will be gone. This depletion of groundwater resources is happening all over the country from the Colorado River Basin to the California Central Valley to the North China Plain to the Middle East (Dimick, 2014).

We cannot fix climate change, however we can mitigate its effects through effective water usage. Using the method of Micro Irrigation also known as drip irrigation, we can conserve water and mitigate the negative effects of water and heat stress on crops. Micro Irrigation involves using pressurized piping that drips water directly on the roots of the plant. It consists of a mainline distribution, sub-mainline (header), drip lines, filters, pressure regulators, and chemical injectors. Laying down an underground network of pipe which has an opening at the base of each plant. Using a pressurizing system to efficiently deliver water directly to the root system of the plant, which is the part that absorbs water (Lamont et al., 2017).

This decreases the water stress on the plants because it ensures that the plants are receiving enough water. Adequate water leads to healthier and more disease resistant crops (Irmak, 2016; Vaughan et al., 2016).

Not only does this method create better living conditions for the plants, it also conserves an incredible amount of water. This will be especially key as water availability decreases with climate change. Drip irrigation improves efficiency of water on farms by reducing the soil evaporation and drainage losses. In terms of conservation, drip irrigation may require less than half the water needed in a sprinkler irrigation method (Lamont et al., 2017). Since the water is applied directly to the roots, no water is wasted on non-productive areas, resulting in even more water efficiency (Lamont et al., 2017). Drip irrigation was much more efficient than furrow irrigation saving 56.4% of the water in comparison. (Tagar et al., 2012,  p. 792).

However, traditional irrigation wastes water in a way that drip irrigation does not. In terms of the framework of increasing water demand with climate change, agricultural methods that recognize water as a valuable, finite resource need to be implemented.  

Furrow Irrigation is cheaper to install initially, but is far more water and energy inefficient compared to drip irrigation. To install, depending on the type of furrow irrigation and the size of the farm, it will be anywhere from $13 to $70 per acre (Wichelns, Houston, Cone, Zhu, Wilen, 1996). There are more repair costs and maintenance costs for this particular type of irrigation and can be anywhere from $13 to $90 annually per acre (Wilchens et al., 1996). While it is cheaper initially, drip irrigation uses water and energy so much more efficiently, that the long term savings of drip irrigation far outweigh the initial cheapness of the furrow irrigation.

Drip Irrigation costs approximately $500- $1,200 per acre, or potentially more, to install (Simonne et al., 2015). For reference, Louisiana Delta Plantation has over 26,000 acres (Honey Brake Lodge, 2017). An acre is about the size of a football field, which would make that farm the size of 26,000 football fields put together. Even at the lowest cost, converting to Drip Irrigation would cost approximately $13 million for the Louisiana Delta Plantation. Even though the initial investment is hard to grasp in terms of magnitude, eventually the system will pay for itself by maintaining crop yields, even in dry years, and lowering energy and water costs (Stauffer, 2010; Lee Engineering, 2017). How much money will be saved and how many years it will take for the new system to pay for itself is largely dependent on the size of the farm and what kind of crop is being grown, therefore, there are not any specific numbers because of the huge variability of farm types and sizes (Stauffer, 2010). In addition, climate change is very difficult to predict precisely enough for long-term cost analysis, and the type of year-to-year predictions necessary to make those calculations are not presently feasible.

Additionally, the drip method is actually shown to increase crop yields by 22%, which itself is motivation for its implementation (Tagar et al., 2012,  p. 792). California almond farmers have seen their crop yields double as they increased their reliance on the micro irrigation system (Block, 2017). Drip irrigation creates better growing conditions by maintaining the correct moisture conditions favorable for crop growth (Batchelor et al., 1996).

However, if the initial investment cost is offset, micro irrigation will save money in the long run. This method of subsidizing the initial cost has been successful in other situations such as in the case of solar panels. An initial investment cost for switching to solar energy can be anywhere between $10,000 and $50,000 (Maehlum, 2014). It would be reduced by thousands of dollars because of the Federal and state tax credits associated with switching to solar power. Eventually, the solar panels will pay for themselves and even save you money in the long term, much like drip irrigation. Largely dependent on how big the house is, how much power is used, and where the house is located, the payback time for switching can vary, but for an average household with a high regular energy cost would be able to payback the initial investment in as little as 15 years (Maehlum, 2014).

A potential source of funding for this initial cost is the federal government. In a recent publication, the United States Department of Agriculture (USDA) showed that they are willing to fund such advancements in the agricultural industry in the name of invasive species, habitat management, soil erosion, and generalized conservation. Since all these factors contribute to the overall health and wellbeing of a farm, efficient watering is logically a top priority for the government.

These programs fall under The Conservation Reserve Program (CRP) which is a program offered by the USDA Farm Service Agency. The CRP is offered as part of an overall program to address invasive species research, technical assistance, and prevention and control that was set up by the USDA in 2015 (United States Department of Agriculture [USDA], 2015). The CRP specifically is a grant based program where the government is willing to supply money to farmers “for establishment of resource-conserving cover on environmentally sensitive croplands.” (USDA, 2015, p. 4). Among other programs, the Environmental Quality Incentive Program, which gives government aid to farmers who want to use more efficient and conservation friendly tools, and the Conservation Technical Assistance Program, which awards tools for conservation to private, tribal, and non federal lands, show a clear willingness for the government to aid in funding programs geared toward conservation and climate change problems (United States Department of Agriculture, 2015). The method under discussion to more efficiently water our farmland is expensive, but clearly the government is willing and able to encourage and fund conservation of farmlands in whatever way possible, even if that means switching to a more efficient water usage irrigation system.

Currently, despite its ability to conserve water, increase crop yields, and mitigate climate change impacts, the use of micro irrigation is not widespread. This is due in part to its high initial investment cost. With grants from the government to offset the initial costs, the system will eventually save money in the long term. A livelihood for farmers like Mike Wissemann, and food for the public like you, are only going to worsen as temperatures continue to rise. Water efficiency is important now more than ever before.

AUTHORS

Jeremy Brownholtz – Environmental Science

Molly Craft – Natural Resource Conservation

Noah Rak – Building and Construction Technology

Mary Lagunowich – Earth System

 

REFERENCES

Batchelor, C., Lovell, C., & Murata, M. (1996). Simple microirrigation techniques for improving irrigation efficiency on vegetable gardens. Agricultural Water Management,32(1), 37-48. doi:10.1016/s0378-3774(96)01257-7

Block, Ben. (2017). “Efficient” Irrigation Tool May Deplete More Water. Retrieved from http://www.worldwatch.org/node/5942.

Coumou, D., Robinson, A., & Rahmstorf, S. (2013). Global increase in record-breaking monthly-mean temperatures. Climatic Change,118(3-4), 771-782.

Dimick, D. (2014, August 21). If You Think the Water Crisis Can’t Get Worse, Wait Until the Aquifers Are Drained. Retrieved from https://news.nationalgeographic.com/news/2014/08/140819-groundwater-california-drought-aquifers-hidden-crisis/

Environmental Protection Agency [EPA]. (2016). Climate Change Indicators. Retrieved from https://www.epa.gov/climate-indicators/climate-change-indicators-drought

Hall, A. E. (2017). Heat Stress and its Impact. Retrieved from http://www.plantstress.com/Articles/heat_i/heat_i.htm

Hansen, L.D., Smith, B.N., & Criddle, R.S. (1998). Calorimetry of plant metabolism: A means to rapidly increase agricultural biomass production. Pure & Applied Chemistry, 70(3).

Honey Brake Lodge. (2017). Louisiana Delta Plantation: About. Retrieved from https://www.honeybrake.com/la-delta-plantation

Irmak, Suat. (2016) Impacts of extreme heat stress and increased soil temperature on plant growth and development. Retrieved from https://cropwatch.unl.edu/2016/impacts-extreme-heat-stress-and-increased-soil-temperature-plant-growth-and-development.

Joint Economic Committee Democratic Staff [JECDS]. (2012). The economic contribution of America’s farmers and the importance of agricultural exports. Washington, DC: U.S. Congress. Retrieved from https://www.jec.senate.gov/public/_cache/files/266a0bf3-5142-4545-b806-ef9fd78b9c2f/jec-agriculture-report.pdf.

Kaufman, Jill. (2016, August 16). Northeast Farmers Grapple with the Worst Drought in Over A Decade. Retrieved from https://www.npr.org/sections/thesalt/2016/08/30/491942025/northeast-farmers-grapple-with-worst-drought-in-more-than-a-decade.

Kromm, David. (2017). Water Encyclopedia: Science & Issue. Retrieved from http://www.waterencyclopedia.com/Oc-Po/Ogallala-Aquifer.html

Lee Engineering. (2017, July 31). 6 Reasons Why Drip Irrigation Pays For Itself. Retrieved from http://lee-engineering.com/irrigation/6-reasons-drip-irrigation-pays/

Lamont, W. J., Orzolek, M. D., Harper, J. K., Kime, L. F., & Jarrett, A. R. (2017, November 2). Drip Irrigation for Vegetable Production. Retrieved from https://extension.psu.edu/drip-irrigation-for-vegetable-production

Maehlum, M. A. (2014, July 18). How Long to Pay Off my Solar Panels? Retrieved from http://energyinformative.org/long-pay-solar-panels/

Osakabe, Y., Osakabe, K., Shinozaki, K., & Tran, L.-S. P. (2014). Response of plants to water stress. Frontiers in Plant Science, 5(86). http://doi.org/10.3389/fpls.2014.00086

Perlman, U. H. (2016, December 9). Irrigation Water Use: Surface irrigation. Retrieved from https://water.usgs.gov/edu/irfurrow.html

Schwarzenbach, V. (2017). Our Story. Retrieved from http://www.warnerfarm.com/our-story/

Shea, Andrea. (2016, August 6). Severe Drought Hits Majority of Massachusetts. Retrieved from https://www.npr.org/2016/08/06/488969852/severe-drought-hits-majority-of-massachussetts.

Simonne E., Hochmuth R., Breman J., Lamont W., Treadwell D., & Gazula A. (2015, October 29). Drip-irrigation Systems for Small Conventional Vegetable Farms and Organic Vegetable Farms. Retrieved from http://edis.ifas.ufl.edu/hs388

Stauffer, B. (2010). Drip Irrigation. Retrieved from https://www.sswm.info/category/implementation-tools/water-use/hardware/optimisation-water-use-agriculture/drip-irrigation

Tagar, A., Chandio, A., Mari, I.A., & Wagan, B. (2012). Comparative study of drip and furrow irrigation methods at farmer’s field in umarkot. World Academy of Science, Engineering and Technology 69, 788-792. Retreived from https://www.researchgate.net/profile/Farman_Ali_Chandio/publication/259346633_Comparative_Study_of_Drip_and_Furrow_Irrigation_Methods_at_Farmer’s_Field_in_Umarkot/links/00b4952b261f3be0ac000000.pdf

Thomson, A.M., Rosenberg, N.J., Izaurralde, R.C., Brown, R.A., & Benson, V., (2012). Climate change impacts on the conterminous USA: An integrated assessment. Part 3. Dryland production of grain and forage crops. Climatic Change, 69(1), 43-65. doi:10.1007/s10584-005-3612-9

United States Department of Agriculture [USDA]. (2015). U.S. Department of Agriculture (USDA) Grant and Partnership Programs that can Address Invasive Species Research, Technical Assistance, Prevention and Control. Washington DC. Retrieved from https://www.doi.gov/sites/doi.gov/files/uploads/USDA%20Grants%20Workbook%20FY%202016%20FINAL%2016%20Oct%202015.pdf

Vaughan, M,. Huffaker, A., Schmelz, E., Dafoe, N., Christensen, S., McAuslane, H., Alborn, H., Allen, L.H., Teal, P.E.A. (2016) Interactive effects of elevated [CO2] and drought on the maize phytochemical defense response against mycotoxigenic Fusarium verticillioides. PloS One. 11(7). doi: 10.1371/journal.pone.0159270

Wichelns D, Houston L, Cone D, Zhu Q, Wilen J. 1996. Farmers describe irrigation costs, benefits: Labor costs may offset water savings of sprinkler systems. Calif Agr 50(1):11-18. https://doi.org/10.3733/ca.v050n01p11.

Yonts, C., Eisenhauer, E., & Varner, D. (2007, June). Managing Furrow Irrigation Systems. Retrieved from http://extensionpublications.unl.edu/assets/html/g1338/build/g1338.htm#target

Protecting Against Climate Change’s Mega-Storms

Evan 11 Comments

 

On August 24, 2017 hurricane Harvey made landfall in Texas as a category 4 hurricane. It was the first major hurricane to hit Texas since 1970 (Allen & Davis, 2017), and it was devastating. The storm delivered a year’s worth of rain in less than a week, being called the wettest tropical storm on record in the United States as affected areas received more than 40 inches of rainfall with peak accumulations of 64.58 inches in just four days (Dart & Helmore, 2017, para 3). The two main flood-control reservoirs that were supposed to protect the Houston area broke. Water levels rose dramatically, damage was increased tenfold, and hundreds of lives were lost. A storm surge of over 12 ft was reported at Aransas Wildlife Refuge, and other areas had storm surges ranging from 3-10 ft as the hurricane stalled over southeast Texas. Hurricane Harvey is the costliest hurricane to ever hit the United States, the damage is so high that it was feared that Texas will not receive enough money to rebuild within a month. Eventually congress budgeted 7.8 billion dollars for recovery efforts, which was only a small fraction of what was truly needed out of the $180 billion that Harvey cost (McWilliams & Parraga, 2017, para 5). After the hurricane, relief efforts were not only attempted by agencies and different government organizations, but also by neighbors and friends. With a disaster as devastating as Harvey, people needed each other to come together and offer relief and support.

It is apparent that climate change is altering the world around us and that hurricanes are becoming more severe as a result. Global warming is changing our oceans, causing a rise in sea surface temperatures, and sea levels, which creates more favorable conditions for intense hurricanes (Mallard, Lackmann, Aiyyer, & Hill, 2013). Hurricanes are classified by the amount of damage they inflict, which is based off of wind speeds and duration of the storm. A category 5 storm is the most severe and a category 1 storm is the least severe. (National Oceanic and Atmospheric Association [NOAA], 2017). Since it is easier for severe hurricanes to form, there has been a global decline in weaker hurricanes with a proportional increase in higher category storms by 2-11% (Holland & Bruyère, 2014, p. 623). We are already seeing the aftermath of such implications; severe hurricanes, which are often classified as a category 3, 4, or 5, cause significantly more damage as opposed to a category 1 or 2 hurricane (Abrams, 2017). A major cause of damage and life loss are the incredible storm surges that large hurricanes cause (NOAA, 2011). High storm surges have been reported in nearly all the hurricanes this past season, including Hurricane Irma, Hurricane Maria, and Hurricane Harvey (“Hurricane Irma”, 2017; “Major Hurricane Harvey”, 2017). Results of these hurricanes have included major flooding and infrastructural damage in affected areas, in many cases overwhelming hurricane defenses already in place (“Hurricane Katrina”, 2009). Hurricane Irma, which recently swept through Florida and the Caribbean, was the first category 5 hurricane to strike the Leeward Islands of Puerto Rico, and is said to be the most intense hurricane to hit the United States since Hurricane Katrina (“Hurricane Irma”, 2017). Just two weeks later hurricane Maria, the tenth most intense hurricane on record swept through Puerto Rico and the Dominican Republic causing catastrophic damage and sending Puerto Rico into a state of emergency (NOAA, 2017). During this past hurricane season, there have been eight big hurricanes which is double the yearly average (Rice, 2017, para 4). Three category 4 and 5 hurricanes have hit the United States in 2017, inflicting severe flooding, which is a first in hurricane history. This trend of bigger, more damaging hurricanes can not be ignored. The current barriers in place are no longer a reliable defence against the greater intensity of these storms.      

Despite the evidence, climate science is still disputed and claims no connection between climate change or its effect on sea surface temperature that ultimately affects hurricane intensity. Nevertheless, the scientific community has reached consensus and agrees that the planet is warming due to climate change (Wang et al., 2016), and that it is affecting storm strength. For each degree Celsius of global warming, there is an 11% increase in the proportion of category 4 and 5 hurricanes, but a 7% decrease in hurricanes that are category 1 and 2 (Holland & Bruye?re, 2014, p. 623). Warming sea surface temperatures have lead to more intense and violent hurricanes with larger storm surges (Kieper, n.d.) causing more and more damage each year to coastal communities in the United States (Dinan, 2017).

Natural disasters such as these are ultimately unavoidable, and there are many people who work to try to predict them in order to protect people from the damage. Anticipating hurricanes and their severity are paramount for providing effective damage and flood protection. Our effect on the climate through anthropogenic climate change has lead to an increase in hurricane intensity causing hurricanes to become bigger and last longer. Our knowledge of how global warming is affecting hurricanes can allow us to prepare more for these storms. The increase of severe, higher category storms will cause more damage than the milder hurricanes we are more accustomed to. As hurricanes intensify, there are greater costs to our economy, infrastructure, and lives (Wang, Li, Zhang, & Ellingwood, 2016; Mallard et al., 2013). There are two major types of damage caused by hurricanes: water damage and wind damage. Wind damage is caused by the high speed winds in a hurricane that can exceed 150 miles per hour which can rip trees out of the ground and move buildings (NOAA, 2017). Water damage is caused by the rain and storm surge associated with the hurricane. Flooding from these events can ruin homes, roads, coastal habitat, and even end lives. Infrastructure that was once used to hold back this storm surge is failing more often as they are overwhelmed by intense storms (Lafrance, 2015). While flood barriers won’t be able to protect communities and the landscape from wind damage, reducing the amount of water damage that will occuring during a hurricane will give people more time to protect themselves against wind damage and reduce the costs of recovering after a hurricane. For example, out of Hurricane Harvey’s 180 billion dollar bill, only 2 billion dollars of the damage was caused by wind (Wattles, 2017, para 9). It is imperative that better flood control and protection be improved and implicated to protect the people and land from severe flooding.    

As seen during hurricane Harvey, the precautions and systems in place are not enough to safely mitigate a storm. Steps that are taken in preparation include: hurricane, tropical storm, and storm surge watches, evacuation, sandbags, rescue cars and boats in case of flooding, and checks of the city’s drainage system (National Hurricane Center [NHC], 2017). No matter the preparation Hurricane Harvey breached levees and flowed over dams. In order to protect ourselves during future hurricanes and their storm surge, flood barriers, a form of levee, should be built along high risk coastlines or inlets. Areas that are at risk are cities built along the coast, which are often densely populated and at least partially below sea level. Cities that fit this criteria are Miami, Florida; New York City, New York; Tampa, Florida; and Virginia Beach, Virginia (Glink, 2013). A flood barrier is a fixed flood gate system that allows water to pass during normal conditions, but in the event of a storm or high water level, the gates are closed which stops water from passing and prevents flooding (European Climate Adaptation Program [ADAPT], 2015). These are improvements on traditional levees, which are typically artificial embankments. These structures are often placed at the mouths of inlets, rivers, or partially along certain low lying coastlines. They work by permanently installing either two gates at either side of an area, or a row of panels underneath the water. In the event of dangerous flooding, the gates swing closed through the water, creating a seal to prevent more water from entering. Or, the panels beneath the water rise, creating a wall against flood water. Flood barriers have been built in several cities throughout the world that are in high danger of flooding.

Other areas have already taken the initiative to bolster their protection against flooding. The Netherlands for example is an extremely prone country to storm surge flooding, since half the country is just one meter above sea level and more than an eighth is below sea level (Kimmelman, 2017). In 1997, the Netherlands built Maeslantkering, a storm surge barrier protecting the city of Rotterdam. At 1,600 ft long, the barrier is a modern engineering triumph capable of protecting Holland from the storm surge and rising sea levels it is so susceptible to (“Maeslantkering”, 2017; Kimmelman, 2017). The Netherlands isn’t the only country to implement this type of technology. Italy completed the Venice Mose Barriers in 2012, which also protects the low lying city from floods and sea level rise. Both countries are at risk of storm surges and have histories of major flooding, and the barriers are effective.

Levees are typically built to withstand a hundred-year flood event, which is an exceptional flood that has about a 1% chance of occurring each year. When a system is built to withstand a hundred year event, it assumes that the event will not change or get worse in that time period (United States Geological Survey [USGS], 2016). This is particularly problematic with global warming, since global warming has been rapidly changes the types of storms we experience, often making them much more severe. Therefore a hundred-year levee can easily become overwhelmed when storms that are more intense and more frequent than it was built for occur, making it essential that we build levees to more long term standards. The Netherland’s flood barrier is built to withstand a 10,000-year flood event. This makes it 100 times safer than the standards set for levees in the United States. Furthermore, since is it is built to last much longer, the Netherlands mandates that the flood control system must be upgraded accordingly to changes in frequency and intensity of flood events, so that the protection stays the same if the threat changes (McQuaid, 2012, para 8). While nothing can stop a hurricane or completely protect against them, more effective and technologically advanced systems can dramatically reduce their impact.

Upgrading our levees and flood barriers are not a foreign idea to the United States. The Army Corps of Engineers is responsible for various homeland duties such as environmental engineering, coastal fortifications, road and canal infrastructure, and disaster relief. With the Army Corps of Engineers’ generous budget and responsibility to preserving our homeland defenses against various threats, including natural ones, the U.S can fund and build select flood barriers, which has been demonstrated in Louisiana after hurricane Katrina in 2005. Hurricane Katrina created the highest storm surge in the U.S’s recorded history at 27.8 ft high (Kieper, n.d., Para 1). New Orleans, the city most devastated by the hurricane, is well below sea level. Before Katrina, it was protected from flooding only by a handful of rundown dams and levees. During the hurricane, all of these systems failed to be enough and residents had fled to rooftops to escape the water as 80% of the city became submerged. Relief was painfully slow, as the hurricane caused over $150 billion in damage and economic costs (“Hurricane Katrina”, 2009; “11 Facts About Hurricane Katrina”, n.d., para 7&8). To fortify the city against such a devastating effect again, the Army Corps of Engineers has built a flood barrier around New Orleans, which should have been in place before Katrina (Burnett, 2015). This individual flood barrier cost approximately $1.1 billion to build; while this may seem like an astronomical number, it is dwarfed by the $150 billion that the storm generated. The Louisiana coast is considered to be much safer with the flood barrier, which is considered a state entity to consolidate and provide better flood control after the hurricane (Burnett, 2015, para 4).

Some may be skeptical of the cost of investment in flood barriers as these systems are expensive and take years to complete. Furthermore, even with our current technology, we cannot guarantee complete safety. Flood protection systems have failed in the past raising questions about our ability to protect our coastal communities, and this concern comes with good reason. When Katrina made landfall in August 2005 as a category 5 hurricane, New Orleans’ levee system, which was designed by the United States Army Corps of Engineers, failed due to high wind speeds, heavy rain, and high storm surge. The city, where 50% of its residents lives below sea level, flooded taking 1,500 lives and causing $108 billion worth of property damage alone (“Hurricane Katrina Statistics Fast Facts”, 2017, para 1). However, advancement in hurricane forecasting has improved our ability to predict future storm intensity. Using this technology the United states Army Corps of Engineers have rewrote the standards used for flood barriers better preparing us for more severe storms and invested a total of $14 billion into improving and the levees and building new barriers to protect New Orleans (Burnett, 2017, para 5). Although, even with the rework of levee standards, retired Lt. General Robert Van Antwerp, the former commander of the Army Corps of Engineers said “though it would not be destroyed by another Katrina, it would most certainly be overtopped leading to many that will still be inundated” (Schleifstein, 2015, para 7). Divesting money from coastal protection should not be an option as the money is an investment in limited damages and is not intended to make our communities completely safe.
 In 2015 the corps agreed that Louisiana’s levee system needed to be reevaluated by 2018. This occurred after Bob Jacobsen, who was hired to run storm surge models, found that many levees in the east bank system would fail if a 200 year storm hit, which has a .2% chance of happening in any given year. Over the next 50 years there will be $50 billion worth of projects improving New Orleans levees with risk reduction and land protection as the goal. The corps have proposed both 400 year and 1,000 year protection plans both costing $59 billion to $139 billion (Schleifstein, 2015, para 32). The corps argue that if we are going to spend the money to protect against a 100 year storm, we might as well go for the most protection possible.

Upgrades to our current flood protection systems will not be enough to protect our coastal communities. It would be most beneficial to build new flood barriers around the cities most in danger from hurricanes. An example of where there could be implemented is New York City, where flood barriers have been considered following Hurricane Sandy in 2012 (McGeehan, 2017). Hurricane Sandy caused widespread power outages, took dozens of lives, and caused billions of dollars in damage (Sharp, 2012). If a simple flood barrier were to be built protecting New York City, it would cost about $11.6 billion, and if three barriers were built along New York coast, the estimated cost is $14.7 billion (Timmer, 2014, para 8). These are costly options, yet Hurricane Sandy caused $65 billion in damage to New York (Rice & Dastagir, 2013, para 2). No matter the price tag on a flood barrier, severe hurricanes rack up a larger one. With the success of barriers in other countries and in New Orleans, barriers are a solution to protect ourselves against dangerous storms as climate change cause worse and worse hurricane events.

This past hurricane season has been swirling through the United States at unprecedented rates. The eight major hurricanes that made landfall along our coasts is double the normal average for the hurricane season (Rice, 2017). Hurricanes are being affected by rising sea surface temperatures, due to global warming. In turn, hurricanes are more intense, occurring more often. This has created a vital need for a more secure defense system against hurricanes and storm surges. In Louisiana and New York, it is agreed that adequate flood barriers would have reduced cost and life loss due to the hurricanes. If better flood barriers were to be built, then the cost could be estimated to be about $12 billion per city, referencing the costs approximated for New York. If we were to build around three cities with the highest risk, then it likely cost $36 billion. While that is a large cost, hurricane Harvey was dramatically larger at $180 billion. Building three barriers does not even equate the cost of a singular hurricane. Providing at risk areas with more effective protection against hurricanes will be undoubtedly beneficial, economically and personally. The damages that hurricanes inflict are far greater than the simple price of building and maintaining effective barriers. The lives, and money, saved are more than enough reason to build flood barriers around dangerous coastal areas.  

AUTHORS

Jennifer Beattie – Natural Resource Conservation

Juliana Berube – Natural Resource Conservation

Tyler Weeks – Building Construction Technology

 

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Climate change results in more intense hurricanes

Evan 14 Comments

 

Susan and her entire family waded from her house in Houston Texas to a neighbor’s home on higher ground the morning that Hurricane Harvey hit in late August. Susan Magee a 44 year old wife and mother of two recounts her story of being evacuated from her home in the wake of of torrential rains.  Waking up her girls and telling them to pack three outfits each was one of the easier parts from her experience. The harder ones were leaving everything except her family, pets, and legal documents. Leaving the only place her two daughters have ever called home. The one space where she and her husband lived together. She acknowledges that her home was not the most spectacular building ever built but says that she did not “mind spending their savings on the down payment” (Holter, 2017). After the devastating results of the storm that was thought to only bring a few inches of water into their home (Holter, 2017), Susan comments that for the meantime they will be staying in a hotel, and are living off of donations and gifts from friends including her friends and more extended family. She sums up her struggle of being in need of assistance and simultaneously proud, she speaks on behalf of her family, when she said that they will not be able to “rebuild our lives without the help of other people” yet at the same time, “we can’t do everything on our own” (Holter, 2017).

The Magees’ home is only one of an estimated 100,000 houses that were affected by Hurricane Harvey this past August (Fessler, 2017). In the wake of Hurricane Sandy, 352,000 people was allocated  $403 million in FEMA assistance (CNN, 2017).  Five years later, many families living on the east coast still cannot fix all of the damage done, in terms of of the thousands of homes completely destroyed, and 90 lives lost (Schlossberg, 2015, para. 3). While we can continually rebuild and replace buildings and homes, we cannot bring back the lives taken in these increasingly worse coastal storms. In the past 30 years, floods have killed more than 500,000 people globally, and displaced about 650 million (Michaels, 2016, para. 1). Hurricane Harvey’s damage is estimated to be about $190 billion in damages, while the costs of Irma are projected to reach $100 billion. These costs burden taxpayers as they entail disruption to business, transportation and infrastructure damages, unemployment periods for many lasting up to months, loss of goods and crop (including 25 percent of orange crop), increased fuel prices, and property damages (Wile, 2017).  The United States government cannot afford the associated costs of building and rebuilding in these increasingly flood prone regions, nor can taxpayers. Because of society’s communal connections to land and region, it is understandable as to why people have chosen to settle their homes and communities on the coast. We have always been infatuated with living close to the beauty of nature, and water systems in close proximity have helped to support communities for centuries (Wilson et. al, 2010).

Instead of trying to dictate over nature or institutions that are intended for communities to seek assistance in order to rebuild and replace, perhaps we should shift our efforts that keep us safe financially and through damages that effect loss of lives and livelihood (Revkin, 2017, Sec. 2). It is the consensus of the scientific community that we are seeing increasingly intense hurricanes due to our warming climate (GFDL, 2017). Coastal communities have reflected devastating costs and damages more than any other community. If we can understand this relationship of increasing hurricanes due to the state of our changing climate, we can be more proactive in our future actions surrounding coastal development. Given that climate change is intensifying hurricanes, we must change the National Flood Insurance program to discourage future building in areas that will be prone to more frequent floods.

In 1968 Congress created the National Flood Insurance program (NFIP) after a series of hurricane-induced disasters.  The federal government got involved in existing disaster assistance programs by providing financial support only if a flood was officially declared to be a major disaster for communities that could not afford to continually support themselves (Lee & Wessel, 2017, para. 3). The NFIP is a federally subsidized program administered by the Federal Emergency Management Agency (FEMA), that enables homeowners, businesses, and renters in participating communities to insure their property if it is at risk of flood damage (Lee & Wessel 2017, para. 2). It was originally planned also that the federal government would make insurance available only within communities that adopted and enforced orders to manage development in floodplains (Lee & Wessels, 2017, para. 4). It has three components: Hazard identification and mapping, Floodplain management criteria and mitigation, and flood insurance (Lee & Wessel, 2017, para. 3).  

Roughly 28.2% of the United States population lives in a coastal hurricane-prone regions according to American Society of Civil Engineers (ASCE) criterion (Crowell, et al., 2010) and half are adopting insurance policies.  The ASCE definition of hurricane-prone regions as areas in the US Atlantic Ocean and and Gulf of Mexico where the wind is more than 90 miles per hour as well as islands off our coasts including but not limited to Hawaii, Puerto Rico, and Guam (ASCE, 2006). While the rates of adopting flood insurance policies among coastal communities is high, it is much lower inland.

When considering how people are able to live in these flood prone coastal zones, origins dates back to development and settlement in the coastal regions of the United States. Floodplain areas, or low-lying areas subject to flooding from a nearby waterbody, were advantageous to inland agricultural communities as a means of irrigation. For economic benefit, large cities were built near rivers and coastlines. This is because residents benefited from lower transport costs since they were close to ports and any trade that occurred there. In modern times we have improved transportation methods which makes this advantage obsolete (Michaels, 2016). Taking this into consideration, many people have lived in these areas for a long time, making it difficult to stop development in these areas where people live (Wile, 2017)

Additionally, the NFIP has incentivized living in these areas, making it not only possible to live here, but an attractive option. When people’s homes get destroyed they are simply able to rely on their flood insurance to rebuild their properties every time they there is damage (Lee & Wessel, 2017, para. 14).  The NFIP incentivizes this by offering low premium rates to those who need to insure their homes against flood damage. Federal funding easily repairs damages, the communities there are very resilient, and are able to keep rebuilding themselves to stay there.

The original objectives of the NFIP were to prevent unwise floodplain development through zonal mapping  ensure that property owners could receive coverage at a reasonable cost, get a large number of communities and property owners to buy insurance, and finally to base premiums on federal assessments of flooding risk so people would be aware of and bear the cost of choices they make (Lee & Wessel, 2017).

Most NFIP insurance policies are sold and run by private insurers under FEMA’s Write Your Own (WYO) program. The WYO is a program designed for FEMA and private insurers to collaborate, under FEMA’s rules and regulations. WYO allows the involved insurers to write and service the Standard Flood Insurance Policy (SFIP) in their own names. As agents of the federal government, the insurers receive an expense allowance for policies and claims processed while the federal government is responsible for underwriting losses (FEMA, 2017 & Marker, 2012). It is important to note that these insurers primarily serve an administrative function. This is a potential flaw with the NFIP because it means they do not bear the burden and associated risks with actually paying insurance claims (Lee & Wessel, 2017). This is problematic because they might be less cautious about building in flood-prone regions.

One issue making it difficult to disinvolve the NFIP from coastal development is the NFIP’s grandfathering rules. Grandfathering ensures that properties re-categorized as being at a higher risk of flooding under revised flood insurance maps will not be subject to large increases (Insurance Information Institute, 2017). Redrawing the flood-risk lines on insurance maps did not affect the low rates of insurance regardless of higher risk zone assessment (III, 2017).

While the NFIP has provided some coastal protection by providing incentives for new homes to be elevated above surge levels as well as strengthening buildings against windstorm damage, there still has been no solution to adapt to issues of increasing of sea level rise and increase of more intense hurricanes (Leathermann, 2017). It is due to lack of strict regulation by the NFIP, that there has been uneven enforcement of building restrictions on the floodplain (Revkin, 2017).

By making insurance for property in coastal regions readily accessible and appealing, the NFIP has led to a large amount of coastal development. The NFIP provides insurance at sizeable discounts for homes and other buildings constructed in flood-prone areas (Kristian, 2017, para. 4). This flood insurance is a federal mandate to have a mortgage in these zones (FEMA, 2017). One proposed idea is an increased premium price to cover and reflect the high risk of floodplain construction (Kristian, 2017, para. 6). This would then discourage vulnerable building plans among those who cannot afford to cover the cost of storm damage. As a result of more people being able to afford insurance in these areas, we have seen more properties being damaged by repeated flooding by increasingly intense hurricanes (Michaels, 2016, para. 3).

Hurricane intensity or severity are defined in a couple of ways. Firstly, we use the category or Saffir-Simpson scale of the hurricane, which is measured by the intensity of winds at the event on a scale of 1 to 5. Storm surge can be used to measure intensity as it examines an abnormal rise in water level on a coast. It is the water from the ocean that is pushed toward the shore by the force of the winds swirling around the hurricane. This advancing surge combines with the normal tides and can increase the water level by 30 feet or more. Storm surge combined with waves can cause extensive damage(US Department of Commerce, National Oceanic and Atmospheric Administration, 2011). Meanwhile, having a landfall hurricane means the eye of the storm reached land (Nosowit, 2012). When examining Sea surface temperature (SST) we found that it is a measurement of energy levels on the top layer of the ocean due to the movement of molecules. Spaceborne measurements give us a global measurement of sea surface temperatures (US Department of Commerce NOAA, 2011). Sea level rise (SLR) is the rise in global sea levels due to increase in temperature caused by release of greenhouse gasses as a result of fossil fuel combustion. The warming atmosphere transfers heat to the ocean’s surface waters and expands its volume (Ocean Health Index, 2017).With a better understanding of the connection between climate change and hurricane intensity, we will be able to implement the steps needed to prevent the associated economic, social, and environmental damages. In order to gain this deeper understanding, the scientific community considered various measures such as increasing SSTs, sea level rises, and landfall hurricanes.

Linear correlation showed there was a significantly high chance (82%) that global temperature  (GT) was causing an increase in SST. When it was tested inversely, for increased SST causing change in GT, it had an insignificant 31% of causality, much lower compared to the other way around. This statistic shows that there is a very high chance warmer global temperatures cause increased Atlantic SST (Elsner, J., 2006). Elsner (2006) explains that as climate change heats the Earth, the seas warm up and store significant amount of energy, which is converted to hurricane wind. This means that with climate change warming global surface temperatures, SSTs are then raised as a result. This increase is SST also has a significant effect on hurricanes. The rise in SST is causing more intense hurricanes. Major hurricanes, which are a Category 3 or higher on the Saffir-Simpson scale-which measures wind speeds to measure potential property damage (NOAA) , may intensify in response to the warming SST associated with global warming (Mousavi et al, 2011). They state that there is an average 8% increase in hurricane intensity for every 1 degree celsius of SST rise (Mousavi et al., 2011, p. 577). These results also indicate that local sea surface warming was responsible for 40% of the increase in hurricane activity relative to the 1950–2000 average between 1996 and 2005, which proved this to be a notably big increase (Saunders and Lea, 2008). This means that tropical hurricanes on Atlantic are extremely susceptible to intensity increase and frequency, with an increase in SST. This leads us to believe an increase in Climate change and GT, is causing more intense hurricanes overall.

Sea Level Rise (SLR) plays a huge role in hurricane intensity. SLR projections show that catastrophic ice-sheet melting, as a result of climate change, estimate SLR increases of 1 m or more over the next century (Mousavi et al. 2011).  This increase in SLR can mean one thing, more fuel for hurricanes and more water for the hurricanes to help the formation of floods. The storm surge is difference in water from normal to flood height (NOAA, 2017). Landfall hurricanes become increasingly dangerous as water is added to create flooding. An increase in SLR will give them the storm surge they need to cause more deadly floods. Balaguru. Et al. (2015) shows there is a 90% increase in storm surge due to SLR when looking at the projection from the Sea, Lake and Overland Surges from Hurricanes(SLOSH) projection. This means the intensity of storm surge in mainly dependent on, and worsened by increasing sea level.  This increase in SLR leads to more storm surge, which in turn causes more floods. A study shows between 1970 and 1999 the highest amount of fatalities during a hurricane was from floods. It also showed floods contributed in approximately 59% of the fatalities during hurricanes (Kaye, 2008).

With climate change leading to both more intense hurricanes and more SLR, we can only expect the number of fatalities and damages to go up from here. If the predictions and the projections are true, the more intense storms with higher SSR will keep doing more damage if we keep on building these coastal communities. As it currently stand there is an average of 28 Billion dollars against an 18 Billion dollar budget (CBO, 2017, slide 4). The projections show this number is going to increase and is going to be a 39 Billion dollars worth of damage versus a 24 Billion dollars budget (CBO, 2017, slide 4). That is why it is crucial to move people away from coastal areas to more inland.

One of the first actions to take is to improve floodplain maps to more accurately describe the flood risk and extent of the floodplain. Floodplain mapping is defined as a system in which the height of the 100-yr flood is estimated with at least a confidence interval of 50%, but the higher the confidence interval level goes the more accurate, more reliable and overall better the map would be (Burby, 2001). Floodplain mapping can help identify the safe locations. This will reduce and discourage development in the remainder of floodplain. One issue is that currently FEMA does not incorporate climate change projections or sea-level rise in their flood insurance maps. As it stands, they state their policy does not map flood hazards “based on anticipated future sea levels or climate change” and that “over the lifespan of a study, changes in flood hazards from sea level rise and climate change are typically not large enough to affect the validity of the study results” (FEMA 2017).  If Federal Emergency Management Agency flood maps incorporated future climate conditions, it would send a ripple effect into real estate and insurance markets. This would be something the public would have to acknowledge. If the federal government made it a legal requirement to have projected climate conditions to be considered in the flood insurance risk maps, construction practices would change to be more precautious (Revkin, 2017). Of course mapping these floodplain areas can also spread awareness. By mapping these and showing them to the community, they can be aware of the dangers, risks and consequences of building in these areas. So instead of doing the cheaper option, they can go the safer way.

People in hurricane zones are able to pay the cheap insurance premium and get subsidized in return after the hurricane damage. These cheaper insurances discourage people to build in other safer area but it prompts them to rebuild in the same area. Enforcing higher flood insurance premiums makes it more difficult to get federal disaster assistance, while reflecting the actual damages (Flavelle, 2017). There is evidence of insurance policies going more towards this direction. In 2012 congress passed the Biggert-Waters Insurance Reform Act, which aimed to extend the National Flood Insurance Program (NFIP) for five years (Kunreuther & Michel-Kerjan, 2017). The main focus of this extension was placing more of the insurance risks onto coastal property owners. When it gets more difficult and more expensive to get federal insurance, the more individuals and local officials would care about where to build, therefore building less in flood risk areas. As it is, when insurance premiums are too low and do not reflect the actual risk of loss, a resulting subsidy on the coastal development encourages people to support sprawling floodplain building (Burby, 2001). This is what we are currently witnessing in coastal communities, and we see it reflected in the sizable 28.2% of the United States population currently living in these coastal regions (Crowell et al. 2010). If they were able to raise the cost, that incentive would be removed. The NFIP cannot accommodate the future scale of  flood damages that are rapidly increasing under a changing climate; a study commissioned by FEMA to help it gain better understanding of this (AECOM 2013) has shown that existing 1% flood hazard zones are fundamentally underestimated given ongoing climatic change (Shively, 2017). Making the insurances more inaccessible, more difficult to get and more expensive would eventually help the community. With more difficult to attain insurance, people will be urged to build in safe floodplain areas, discouraging further development in flood zones. (Flavelle, 2017; Burby 2001). If it becomes unattainable, development will be forced more inland.

There is no doubt that raising premiums and making insurance less accessible will be difficult to pass initially. This is because homeowners will not want their insurance costs raised, and homebuilders will not want to be out of business if coastal development is discouraged. For homeowners, if the premium is raised they might benefit from moving to a safer region inland. In doing this, we believe that the burden of losing their belongings and endangering their families will be eased. While many items can arguable be replaced by insurance, there are a fair amount of things that are irreplaceable. They also will not suffer from the economic loss of unemployment periods, associated with the damage from hurricanes in these flood regions (Wiles, 2017). As for homebuilders, if the rates increase they might lose money at first. Everyone moving away from the coastal communities and less people building near the coast will have an impact on them in the beginning, but over time they would have more chances to build bigger and better complexes away from the flood risk without their building and houses being destroyed. It can also provide the homebuilders with a safe community they can live in themselves with their families (Friedman & Scism, 2017).

We propose that the package of bills proposed by the House Financial Services Committee, pushed by Chairman Jen Hansarling (R-TX) be passed into law. The bill package would renew the NFIP program for five years. It would also enact the raise of insurance premiums, which we advocated for. In doing so it would make coverage more expensive for policyholders, and make it easier for private companies to sell their own flood insurance policies (Lee & Wessel, 2017). We also propose the passage into law of the House and Senate backed bill called; Sustainable, Affordable, Fair and Efficient (SAFE) NFIP Reauthorization Act. This bill supports what we suggested as it calls for greater investments in flood risk mapping and risk mitigation (Lee & Wessel, 2017).

AUTHORS

Amir Entekhabi – Environmental Science

Rachel Finn – Natural Resource Conservation

Keren Radbil – Agricultural and Environmental education

 

REFERENCES

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Development on U.S. Hurricane Damage: Implications for the Federal Budget. Retrieved from: https://www.cbo.gov/system/files/115th-congress-2017-2018/presentation/53244-presentation.pdf.

Crowell, M., Coulton, K., Johnson, C., Westcott, J., Bellomo, D., Edelman, S., & Hirsch, E. (2010). An estimate of the US population living in 100-year coastal flood hazard areas. Journal of Coastal Research, 201-211. DOI 10.2112/JCOASTRES-D-09-00076.1

Effects of Climate Change and Coastal Development on U.S. Hurricane Damage: Implications for the Federal Budget. (2017, November 02). Retrieved December 04, 2017, from https://www.cbo.gov/publication/53244

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Friedman, N., & Scism, L. (2017, October 23). What Could Raise Hurricane Irma’s Costs? Letting Contractors Handle Claims. Retrieved November 29, 2017, from https://www.wsj.com/articles/what-could-raise-hurricane-irmas-costs-letting-contractors-handle-claims-1508756401

Flavelle, C. (2017). Hurricanes Highlight Failure to Enforce Flood Insurance Rules. Bloomberg Businessweek. Retrieved from: https://www.bloomberg.com/news/articles/2017-09-13/hurricanes-highlight-failure-to-enforce-flood-insurance-rules.

Fessler, P. (2017, September 01). At Least 100,000 Homes Were Affected By Harvey. Moving Back In Won’t Be Easy. Retrieved December 04, 2017, from https://www.npr.org/2017/09/01/547598676/at-least-100-000-homes-were-affected-by-harvey-moving-back-in-wont-be-easy

Holter, L. (2017, August 31). I Lost My Home In Hurricane Harvey. Retrieved December 04, 2017, from http://www.refinery29.com/2017/08/170287/lost-my-home-hurricane-harvey-flood

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Insurance Information Institute. (2017). Retrieved from: https://www.iii.org/publications/insurance-handbook/insurance-and-disasters/background-on-flood-insurance

Kristian, B. (2017). The Week. Retrieved from: http://theweek.com/articles/721185/perverse-incentives-national-flood-insurance-program

Kaye, K. (2008, July 12). Inland flooding causes most hurricane deaths. Chicago Tribune. Retrieved from: http://www.chicagotribune.com/sns-cane-inlandfloods-story.html

Leatherman, S. P. (2017). Coastal Erosion and the United States National Flood Insurance Program. Ocean & Coastal Management. Chicago. DOI 10.1016/j.ocecoaman.2017.04.004.

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Nosowitz, D. (2012, October 29). The Dictionary Of Hurricane Sandy: Landfall. Retrieved October 20, 2017, from https://www.popsci.com/science/article/2012-10/dictionary-hurricane-sandy-landfall

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The Arctic National Wildlife Reserve: Save the Caribou

Evan 21 Comments

 

Every year in April, there is a herd of nearly 197,000 caribou that travel more than 400 miles to reach the plain on Alaska’s northernmost coast. This massive herd is known as the Porcupine Caribou herd and for several months of the year, this Alaskan coastal plain will be their home. It is where the females give birth every June and where the young spend the first weeks of their lives. This area is known as the Arctic National Wildlife Refuge (ANWR) and it provides vital habitat for the Porcupine herd every spring and summer as the place where they can safely birth their calves and begin to raise them (U.S. Fish and Wildlife Service, 2016).  

The National Wildlife Refuge System was first put into place by President Theodore Roosevelt more than a century ago (“Political History of the Arctic Refuge,” 2014). Wildlife Refuges are meant to serve the sole purpose of providing and restoring habitat for animals in the wild (Berman, 2015, para. 9). Several decades later in 1954, the National Park Service began surveying areas in Alaska that would be worth protecting under the Refuge System based upon their wildlife diversity, aesthetic values, and recreational opportunities. Almost nine million acres in the northeastern corner of Alaska were deemed valuable according to these standards and in 1960, ANWR was established. Today, this preservation area has expanded to nearly 19 million acres. The Refuge is home to a diverse collection of wildlife that includes eight types of marine mammals, 37 species of land mammals, 42 fish species, and over 200 bird species with its most notable species being caribou, polar bears, and muskoxen (U.S. Fish and Wildlife Service, 2013).

The northernmost piece of the ANWR is a one and a half million acre plain that borders the coast of the Arctic Ocean. This particular part of the Refuge is referred to as the 1002 area (U.S. Geological Survey, 2016). Currently, it is not considered Wilderness because it is a vast frozen coastal plain without trees, mountains, or lakes (Energy Research, n.d.). However, this is the esteemed coastal plain that the Porcupine Caribou herd migrates to each spring and relies upon as the habitat in which more than 40,000 calves are born each year (U.S. Fish and Wildlife Service, 2016; Warden and Johnson, 2015).

Unfortunately, the 1002 area in the ANWR has been being considered for oil exploration since 1980. Today, there is a strong push being made by Alaskan politicians to open up this area for oil drilling. It is estimated that this coveted coastal region holds anywhere from four to twelve billion barrels of oil (Reiss, 2017). According to the U.S. Geological Survey (2016), approximately 10.4 million barrels of this oil are actually recoverable, which translates into about one million barrels per day for the 1002 area. Based on these estimates, ANWR would be producing more oil than any other field in North America. Within the ANWR, 7.16 million acre are currently protected under the Wilderness Act and that does not include the 1002 area (Energy Research, n.d.).

One of the most outspoken proponents for drilling in the ANWR is Alaska’s Republican senator, Lisa Murkowski. She is fighting hard for the rights to drill in the 1002 Area of ANWR as a means to boost the Alaskan economy (Murkowski, 2017). Murkowski argues that opening the 1002 Area to drilling would lead to a massive increase in jobs available for Alaskans and that it will mean billions of dollars of revenue for the state as well (Murkowski, 2017, para. 6). While oil drilling may benefit the state in the short term, it would only make Alaskans more dependent on fossil fuels at a time when the fossil fuel industry is becoming less and less popular (Grant, 2017, para. 3). Meaning that in the long run, the jobs created now for drilling would not last as less oil becomes used worldwide and greener technologies emerge to take its place. In addition to this, the drilling would also create a series of negative impacts to the environment that include excessive noise levels, slow ecological recovery, emissions, and sea ice danger.

The negative ecological effects of oil drilling in the ANWR 1002 area far outweigh the benefits, therefore it should be declared a Wilderness area in order to protect wildlife and the environment from the impacts of drilling activities. The distinction of Wilderness gives the strictest regulations possible for public land protection. Becoming designated Wilderness would make it illegal to drill for oil in the 1002 area (Sanders, 2015, para. 3). Keeping oil rigs out of the area would prevent harm to the caribou herds and other wildlife that rely on the 1002 area for habitat because they would not have to migrate elsewhere to avoid the noise levels and pollution. The Porcupine caribou are an important part of the ecosystem of the 1002, both depending on the environment they live in as well as enriching it (PCMB.ca, 2017).

Ecologically, we should care because of the negative effects oil exploration and drilling will have on the surrounding ecosystem. Noise pollution from oil fields in the 1002 area causes the Porcupine Caribou to cease migration to the coastal plains for calving season. When noises from the drilling exceed 75 decibels, many animals are unable to tolerate it and will avoid those areas (Drolet, Côté, and Christian , 2016). Thus, oil drilling will cause a decrease in the caribou population because it would drive them away from the calving grounds that they have relied upon for generations to raise their young in. Caribou are one of the most prominent animals in the northern Alaskan landscape. One study simulated what would happen to their populations if onshore oil rigs develop near their habitat. The study found that when subjected to the harshest development scenario of 15 rigs, all open for leasing, the caribou lost 34% of their habitat used for calving grounds when they were forced out of it by drilling the effects (Wilson et al., 2015). Excessive noise levels from the drilling activity causes these animals to migrate from their high-quality sites into areas that are less suitable for their needs (Drolet et al., 2016).

According to Griffith et al. (2002), pregnant female caribou will not cross over or under oil industry infrastructure during calving season (p. 40). This creates a large problem since the females are usually pregnant when they migrate to Area 1002 every June (U.S. Fish and Wildlife Service, 2016, para. 4). This could mean that they are unable to reach the area and may not be able to properly give birth and raise healthy calves. Additionally, caribou forced to migrate from their habitat in the safe coastal plains to the mountains may likely run into many more predators, such as grizzly bears and wolves. According to Griffith et al. (2002), grizzly bears’ habitat is primarily in the mountainous foothills and there has never been a report of wolf dens on the coastal plains (p. 51). Without trees or mountains in the 1002 area, these animals are not very present on the plain, thus making it safer for the caribou to be there than further inland where those predators are more abundant.

The environment in the ANWR is very sensitive to anthropogenic disturbances due to the brutal climate that allows for a short growing season for vegetation to recover from any damage. This slow ecological recovery puts the wildlife, such as the caribou previously discussed, in danger of not having enough food supply. The anthropogenic changes in the ANWR will be detrimental to the vegetation, like grasses, mosses and small shrubs. The pollution released by these oil sites causes death or illnesses that eventually lead to death to surrounding animals (Arctic National Wildlife Refuge, 2016). Therefore, the overall pollutants from oil exploration have negative impacts on both the habitat and migration of wildlife in the ANWR 1002 area.

Being how remote and wild this land truly is, it is not often traveled. This is also true for Prudhoe Bay, where there is currently oil drilling occurring. According to Barringer (2006), there was a spill comprised of 267,000 gallons of crude oil across two acres along Alaska’s North Slope (para. 1). The spill took five days to detect due to it starting as pin sized hole that expanded under pressure and most of the oil seeping under the snow (Barringer, 2006, para. 3-4). Inspections of the pipe showed that the almost 40 year old pipe had increased corrosion but not enough to worry about. The leak was also too small for system to detect so nobody knew (Barringer, 2006, para. 9-10). This is not the only spill from this pipeline however, there was an 11 million gallons spill in 1989, a 700,000 gallon spill in 1978 and a 285,000 gallon spill in 2001 (para. 7). Spills happen no matter how careful the companies are. A spill like this could force the Porcupine Caribou out of even more of their habitat.

Oil drilling in the ANWR would have economical value to Alaska, however in the grand scheme this value is outweighed greatly by the negative ecological impact it would have. The noise from the oil rigs is too loud for the Porcupine Caribou herd to tolerate and would force them out of their environment (Drolet et al., 2016). This would also disrupt their migration patterns because a pregnant female will not cross under or over any oil infrastructure (Griffith et al., 2002, p.40). This makes the routes that they can take even more selective if not impossible. In addition the herd would have to move into the mountains, where their predators are, which would lead to fewer offspring surviving (Griffith et al., 2002). If all of this still isn’t enough the herd could end up running out of food. The Arctic has a slow ecological recovery with a very short growing season due to the nature of the climate (Arctic National Wildlife Refuge, 2016). Not only is their land being taken by the oil rigs, but also their food sources. Making the ANWR completely designated as Wilderness would make drilling illegal (National Parks, 2012, para. 6) protect this herd for years to come while also preserving the pristine piece of land that is truly left without human interference.

AUTHORS

Adam Mergener – Building Construction Technology

Ashley Casello – Natural Resource Conservation

Kevin Boino – Environmental Science

 

REFERENCES

Arctic National Wildlife Refuge. (2016, September 19). Retrieved from http://www.defenders.org/arctic-national-wildlife-refuge

Barringer, F. (2006, March 15). Large Oil Spill in Alaska Went Undetected for Days. Retrieved from http://www.nytimes.com/2006/03/15/us/large-oil-spill-in-alaska-went-undetected-for-days.html

Berman, A. (2015, September 28). Park vs. refuge: What’s the difference? Retrieved from  https://www.mnn.com/earth-matters/wilderness-resources/stories/park-vs-refuge-whats-difference

Drolet, A., Côté, S. D., & Christian, D. (2016). Simulated drilling noise affects the space   use of a large terrestrial mammal. Wildlife Biology, 22(6), 284-293. doi://dx.doi.org/10.2981%2Fwlb.00225

Energy Research, I. F. (n.d.). ANWR. Retrieved from https://instituteforenergyresearch.org/topics/policy/anwr/

Grant, M. (2017, October 19). Oil Drilling in Arctic National Wildlife Refuge Imperils Wildlife, Won’t Solve Economic or Energy Challenges. Retrieved from http://www.nwf.org/Home/Latest-News/Press-Releases/2017/10-19-17-Arctic-Oil-Drilling

Griffith, B., D. C. Douglas, N. E. Walsh, D. D. Young, Jr., T. R. McCabe, D. E. Russell, R. G. White, R. D. Cameron, and K. R. Whitten. 2002. The Porcupine caribou herd. Pages 8-37 in D. C. Douglas, P. E. Reynolds, and E. B. Rhode, (eds.). Arctic Refuge coastal plain terrestrial wildlife research summaries. USGS Biological Science Report USGS/BRD/BSR-2002-0001

Murkowski, L. (2017, November 01). Time is right to open a slice of ANWR to drilling. Retrieved from https://www.adn.com/opinions/2017/11/01/time-is-right-to-open-a-slice-of-anwr-to-drilling/

National Parks, National Forests, and U.S. Wildernesses. (2012, April 18). Retrieved from http://www.pbs.org/wnet/nature/river-of-no-return-national-parks-national-forests-and-u-s-wildernesses/7667

Pcmb.ca. (2017). Porcupine Caribou Management Board. Available at: http://www.pcmb.ca.

Political History of the Arctic Refuge. (2014, November 23). Retrieved from http://anwr.org/2014/11/political-history-of-the-arctic-refuge/

Reiss, B. (2017, September 15). Bolstered by Trump, big oil resumes its 40-year quest to drill in an Arctic Wildlife Refuge. Fortune. Retrieved from http://fortune.com/2017/09/15/donald-trump-big-oil-alaska-arctic-wildlife-refuge/

Sanders, S. (2015, January 25). Obama Proposes New Protections for Arctic National Wildlife Refuge. Retrieved from https://www.npr.org/sections/thetwo-way/2015/01/25/379795695/obama-proposes-new-protections-for-arctic-national-wildlife-refuge

U.S. Fish and Wildlife Service. (2013). Arctic: Wildlife & habitat. Retrieved from http://www.fws.gov/refuge/arctic/wildlife_habitat.html

U.S. Fish and Wildlife Service. (2016, December 6). Caribou – Arctic – U.S. Fish and Wildlife Service. Retrieved from https://www.fws.gov/refuge/arctic/caribou.html

U.S. Geological Survey. (29 November 2016). Arctic National Wildlife Refuge, 1002 Area, Petroleum Assessment, Including Economic Analysis. Retrieved from https://pubs.usgs.gov/fs/fs-0028-01/fs-0028-01.htm

Warden, A. and Johnson, D. (2015). Wilderness is the right designation for ANWR’s coastal plain. Alaska Dispatch News. Available at: https://www.adn.com/commentary/article/keep-arctic-refuge-wild/2015/12/18/

Replace Hydropower Dams to Save the Southern Resident Orca Whale Population!

Evan 21 Comments

 

On August 8th 1970, the southern resident orca whale population was ambushed off the coast of Penn Cove, Washington in one of the most infamous whale captures in history (WDC, 2017). This capture involved 80 whales, in which 7 were collected and 5 were killed (WDC, 2017).  The only current living orca from this incident is Lolita (WDC, 2017). She is now the oldest living killer whale in captivity and lives in what is arguably too small of a tank (Save Lolita, n.d; Herrera, 2017). It’s believed that Lolita’s tank doesn’t meet the minimum 48 feet horizontal dimension requirement set by the United States Department of Agriculture (USDA) (Herrera, 2017). Lolita has a 60 foot tank obstructed by a ‘work island’ that separates her pool into two 35 feet sections (Herrera, 2017). Another issue Lolita faces in captivity is solitude (which is abnormal for social animals such as orcas) (Save Lolita, n.d). Due to animal rights advocacy groups making these issues well known to the public, Lolita has become both a symbolic example for why orcas can’t feasibly be kept in captivity and a famous icon for the southern resident orca population. This killer whale population is currently estimated at 80 whales consisting of 3 pods named the J,K and L pods (NOAA Fisheries, 2015). In the fall, spring and summer their territory ranges from waterways near the U.S.-Canadian border to inland waterways in Washington state ( NOAA Fisheries, 2015).

The southern resident orca whale population is also vital for Washington state’s economy. These whales benefit the state’s economy by providing tourism revenue through whale watching (Grace, 2015). The number of people going on whale watches in Washington has even increased over time; from 1998 to 2008, Washington state saw an increase of 108,000 whale watchers and a 3% average annual growth rate (O’Connor, 2009). Due to this increased whale watching tourism, wildlife watching activities (such as whale watching) created over 21,000 jobs in Washington State, yielded $426.9 million in job income, and generated $56.9 million in state tax revenue all in 2001 (Grace, 2015, para. 4). People are also estimated to spend nearly $1 billion annually in Washington viewing wildlife (O’Malley, 2005, para. 1). It’s also estimated that the southern resident orca population itself adds minimally 65-70 million dollars to Washington state’s economy (Grace, 2015, para. 1).

Sadly though, despite all the intrinsic and economic benefits these orcas bring to Washington state, they are facing the threat of extinction. In fact, the southern resident orca population was even added to the endangered species list in 2005 (NOAA fisheries, 2015).They were added to this protection list because the population has fallen from an estimated 200 whales in the late 1800s to a current estimate of 80 whales (NOAA Fisheries, 2015). This population decline even lead to the production of a recovery plan by the National Marine Fisheries Services (National Marine Fisheries Service, 2008). This plan addresses specific potential threats to the southern resident orca population such as prey availability, pollution, vessel effects, oil spills, exetera and outlines goals to minimize these threats and their harm to orcas (National Marine Fisheries Service, 2008). One of the believed reasons behind the orcas small population size is a limited abundance of salmon from the Snake and Columbia rivers (Baker & Peterson, 2017). The southern resident orcas rely on Columbia and Snake river salmon as a food source during the summer when they live in waters off the San Juan Islands that lie northwest of Seattle (Baker & Peterson, 2017). Salmon are an essential food source for these whales because resident killer whales only prey on fish, not other marine mammals (such as seals or sea lions) (Ford et al., 1998, 2009). The Columbia River itself is also especially crucial for southern resident orcas as they display unique feeding behavior there not seen at any other territorial location; they stock up on salmon by sitting at the mouth of the river for days and foraging (Baker & Peterson, 2017). It’s also believed the declining salmon population is a key reason behind the southern resident orcas low population because orcas are predators at the top of their ecosystem’s food chains and don’t serve as prey for other animals (Ford, 2009). Therefore, predation of orcas cannot be considered a valid source for their population decline. As a result, the decreasing salmon population in the Columbia and Snake Rivers has added pressure to the orca population over the past three decades (Baker & Peterson, 2017). The Center for Whale Research and the Center for Conservation Biology (University of Washington) found that low salmon populations also lead to enough nutritional stress to cause two-thirds of  southern resident orca pregnancies to fail between 2007 and 2014 (Baker & Peterson, 2017).The majority of the salmon this whale population consumes also originates from the Snake river, a tributary of the Columbia River (Barker & Peterson, 2017). In short, the southern resident orca population is critically endangered and low salmon populations are putting even more stress on the whales (Barker & Peterson, 2017; Ford 2009). If the northwest salmon population is not restored, it could result in the disappearance of resident orcas in the northwest forever.   

Since 1991, twelve specific populations of Columbia River Basin salmon and steelhead have been protected under the Endangered Species Act (Harrison, 2016). For Snake River Salmon the National Marine Fisheries Service noted that the estimated annual returns of spring/summer Chinook declined from 125,000 fish between 1950 and 1960 to just 12,000 fish in 1979 (Harrison, 2016). Proposed recovery plans have also started legal battles over what actions are necessary to avoid further jeopardizing the species (Harrison, 2016). This debate is complicated by hydropower dams directly affecting salmon and steelheads (Harrison, 2016). These hydropower dams on the Columbia and Snake rivers are inhibiting growth of the river’s salmon population by creating habitat fragmentation, causing direct mortality and decreasing their food supply (Harrison, 2008).

At 1,954 kilometers long, the Columbia river is the 15th longest river in North America; its tributaries and it form the dominant water system in the Pacific Northwest as it drains into seven different western states (Bonneville Power administration , 2001). The history of the dams on the Columbia and Snake rivers date back to Theodore Roosevelt’s presidency, as the construction of the first dam on the Columbia river (the Rock Island dam) began shortly after his election with the sole intention of producing electricity (Harrison, 2008) . By 1975 the Columbia river had four more large dams constructed on it and has had smaller dams constructed on it since (Harrison, 2008).  

These dams inhibit the river’s salmon population because they fragment rivers and therefore impede salmon migration. This negatively impacts the reproduction of the Columbia and Snake river salmon because they then cannot spawn effectively upstream. Salmon need to navigate between spawning sites, rearing habitat (juvenile living space) and the Pacific Ocean in order to reproduce. Salmon hatch in rivers and then travel to the ocean for their adult lives  (National Park Service’s, 2017). Then when they are ready to spawn again, instincts guide them back to their birthplace to spawn (National Park Service’s, 2017). There are also case studies to show that dams, like the ones present in the Snake and Columbia river, prevent the salmon from properly spawning upstream. For example, the presence of the Hemlock Dam on Trout Creek, Washington, USA was linked to the impeded migration of  U.S. threatened Lower Columbia River steelhead (a type of salmon) and other migratory fish by blocking their migration path (Claeson & Coffin, 2016, p. 1144). It is also known that the dams in the Columbia river basin now block more than 55 percent of the spawning and rearing habitat once available to salmon and steelhead (Harrison, 2008).

Dams not only block the upstream passage of adult fish but block the downstream passage of juvenile fish as well. Hydroelectric dams (such as the ones on the Columbia and Snake rivers) compound this problem because they force migrating fish to travel through turbines without a bypass systems (Harrison, 2008). This is a problem for migrating salmon because the spinning blades and/or concrete walls in these turbines could kill or injure juvenile fish drawn in by the current (Harrison, 2008). Biologists estimate that fish drawn through a turbine passage has a 10 to 15 percent chance of dying (Harrison, 2008). This is problematic due to the Snake and Columbia river having multiple hydroelectric dams that increase each fish’s chance of dying by forcing them to travel through turbines to migrate (Harrison, 2008).

The dam’s on the Columbia and Snake rivers are also negatively impacting the salmon populations chance of survival by limiting their sources of food. The hydroelectric dams are doing this by limiting the growth of benthic insects (mayflies,stoneflies, caddisfly nymphs) populations within the rivers. Dams are known to limit benthic insect population growth by increasing water temperatures (Claeson & Coffin, 2016).  Dams increase water temperatures by creating reservoirs that isolate water and create a slow flow over the dam that increases the reservoir’s water and discharge temperature (Claeson & Coffin, 2016). In warmer waters, desirable salmon food sources such as mayfly, stonefly and caddisfly nymphs die off and are replaced by other insects (midges and mosquito larvae) that are much less desirable as food for salmon (Effects of Elevated Water Temperatures on Salmonids, 2000).  Cold water fish such as salmon relay on benthic insect populations as a source of food and decreasing benthic insect populations makes an environment unsuitable for salmon to live in (Claeson & Coffin, 2016, Harrison, 2008).  

The best plan to solve this problem and save both the salmon and orca whale population would be to remove the dams from the Columbia and Snake rivers. Removing the dams would help restore the salmon population that the southern resident orcas so heavily rely on. There have been previous dam removals in the Columbia and Snake river area that have resulted in a successful increase in salmon population. In 2012, removing the Condit Dam from the White Salmon River (a tributary to the Columbia River) restored upstream migration access for the first time in 100 years (Allen et al., 2016, p.192). The number of redd counts (the number of salmon spawning nests) shows the increase in the salmon population (Allen et al., 2016, p.197). In the pre-dam model for the Tule fall Chinook Salmon it’s redd count increased by 60% since dam removal and the Upriver bright fall Chinook Salmon redd count increased from no abundance to around 4,251 redds after dam removal in 2013 (Allen et al., 2016, Table 2). This dramatic increase in spawning means a greater number of salmon are being produced. Other large dam removals include Washington State’s Glines Canyon Dam and the Elwha Dam hydroelectric dam. These dams were removed in 2011 (Nijhuis, 2014). Now salmon can be seen migrating past the former dam sites and as salmon populations recover, research expect the whole food web to benefit (Nijhuis, 2014). These cases set forth by the Condit, Glines Canyon and Elwha Dam removal is further evidence that dam removal in the region can be beneficial to the salmon population.

While these cases have made it clear that dam removal is the best option to restore the salmon population, there are other options available. Alternative methods such as a permanent adult fish ladder can be seen on the Lower Granite Dam (Conca, 2016). However, fish ladders can be problematic because they elevate water temperatures to form a “thermal barrier” that stops adults from migrating upwards into warm waters (Conca, 2016). One method the US Army Corps of Engineers attempted to face this problem was releasing Dworshak reservoir water in to cool the Snake River (Lower Granite Adult Fish Ladder Temperature Improvement System, 2016). Another alternative method is  “daylighting” juvenile fish passage (Conca, 2016).  This is when  juvenile fish passage is allowed through a large elevated bypass flume leading to the Juvenile Fish Facility just downstream of the dam (Conca 2016). Save Our Wild Salmon (a nationwide coalition working to restore salmon and steelheads to the rivers) also argues that the federal government is relying on these unreliable alternative methods such as barging and trucking salmon around the dams and limiting the amount of water in the river (Bogaard, 2017). Implementing these alternative methods have already cost billions of dollars to the US taxpayers and over the past twenty years, researchers still also haven’t found conclusive evidence that federal salmon recovery actions succeeded in helping restore these fish (Bogaard, 2017). Federal agencies have spent more than $8 billion in attempts to restore Columbia and Snake River salmon (Bogaard, 2017). Each year more than $550 million in funding goes to NOAA Fisheries, the Army Corps of Engineers and other federal agencies for this effort (Bogaard, 2017). Removing these dams could be cheaper than these other restoration efforts and revive both the salmon and orca populations. Advocates for dam removal also argue that the removal of these dams is a viable option because they produce most of their power in the spring when it’s not crucial for Northwest power supplies, and it would be relatively simple and inexpensive when comparing the cost to other alternative methods  (Baker & Peterson, 2017).

The main reason some are still resistant to removing these dams is because they provide a significant source of hydropower. There are four main hydroelectric power providing dams on the Snake river; these are the ICE Harbor, Lower Monumental, Little Goose and Lower Granite Dams (Conca, 2016). According to Conca (2016) Ice Harbor Dam produces 1.7 billion kWhs/yr, Lower Monumental dam produces 2.3 billion kWhs/yr, Little Goose dam produces 2.2 billion kWhs/yr and Lower Granite dam produces 2.3 billion kWhs/yr. (Conca, 2016). Washington’s hydroelectric power provides more than two-thirds of Washington’s net electricity generation and almost nine-tenths of the state’s renewable power generation (U.S Energy Information Administration, 2017). As for the Columbia river, The Grand Coulee Dam is the largest hydroelectric power producer in the United States, with a total generating capacity of 6,809,000 kilowatts (U.S Energy Information Administration, 2017). The communities that depend on the Snake and Columbia river’s hydroelectric dam power are then faced to question if there are potential ways to provide Washington state a renewable energy source that doesn’t hurt the salmon population . To end this debate an alternative energy source (specifically wind energy) needs to replace the hydropower provided by the dams on the Snake and Columbia river so that the dams may be removed.

This replacement energy source absolutely needs to be renewable because Washington passed renewable energy standard (RES) legislation in 2006 that requires certain utilities to have fifteen percent of their electricity sales from renewable resources by 2020 and to invest in energy efficiency (American Wind Energy Association, 2014). One viable, renewable energy source that may be used to replace hydroelectric power provided by these dams would be wind energy. In fact, in 2015 Washington ranked ninth in the nation in wind energy electricity generation (U.S Energy Information Administration, 2017). There are still some skeptics regarding the reliability of wind turbines and their ability to produce enough power to feasibly replace other energy sources.  For example, some claim that wind turbines are unpredictable, not dependable enough for consistent power generation and only produce 8% of their total system capacity (Edmunds, 2014).  However, this is mostly incorrect and invalid in this case. Wind energy has already proven itself feasibly reliable in Washington, it’s the state’s second largest renewable energy generation contributor with over 3,000 megawatts of installed capacity (U.S Energy Information Administration, 2017). This can be compared to the 6,910 megawatts of hydroelectricity generated Washington net electricity (U.S. Energy Information Administration – EIA – Independent Statistics and Analysis, 2017). Wind energy is also relied upon as a common renewable resource of choice to meet renewable energy legislation requirements (American Wind Energy Association, 2014).

New wind turbine farms to replace the hydroelectric dams can be installed by PSE (Pudget Sound Energy), the largest Northwest utility producer of renewable energy (Hopkins Ridge Wind Facility). They own and operate the large wind farms including the Hopkins Ridge Wind Facility located in Columbia County (Hopkins Ridge Wind Facility). The Hopkins Ridge Wind Facility started in 2005 and consists of 87 turbines  producing an average annual output of about 465,000 megawatt hours, sufficient to power 41,000 households (Hopkins Ridge Wind Facility). If more winds farms like Hopkins Ridge Wind Facility were developed to help the state of Washington develop more wind energy, the people of Washington wouldn’t need the hydroelectric power provided by the dams and they could be removed to help prompt orca and salmon population recovery.

The best possible solution for this issue is to harness and develop more wind energy in the state of Washington. This energy replacement will allow for the dams to be removed without depriving the people of Washington of electricity. Being able to remove these dams is critical for the survival of the salmon population within the Columbia and Snake rivers. Sustaining the salmon population is critical for the survival of the southern resident orca population (a beloved tourist attraction in the state of Washington). Saving the salmon population will also help the National Marine fisheries service in achieving the recovery plan outlined for southern resident orca whales in 2008 (National Marine Fisheries Service. 2008).  In short, finding an alternative renewable energy source to replace the dams on the Columbia and Snake rivers is imperative for the survival of the salmon and orca whale populations affected by these dams. Lolita the orca was taken from this population and is now suffering as a result (Save Lolita, n.d.; WDC, 2017). She serves as an example of how hard captivity is for orcas and why preserving the southern resident population in the wild is their only true chance for survival.

AUTHORS

Marilyn Donovan – Animal Science: Pre-vet

Lauren Baldwin – Environmental Science

Connor Taylor – Environmental Science

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Green roofs: an analysis on air pollution removal and policy implementation

Evan 30 Comments

 

In October 1948, a thick cloud of air pollution formed above the industrial town of Donora, Pennsylvania. It lingered for five days, killed 20 people and induced sickness in 43% of the town (Environmental Protection Agency, 2007). Pollution poses a serious threat to our environment and health. Nearly one-quarter of the people in the U.S. live in areas with unhealthy short-term levels of particle pollution, and roughly one in ten people live where there are unhealthful levels year-round (American Lung Association, 2010). Air pollution is of particular concern to public health as it is the cause of hazards including upper respiratory irritation, chronic respiratory irritation, heart disease, lung cancer, and chronic bronchitis (Kampa & Castanas, 2008). The most common health-related impacts from air pollution are increased occurrences of respiratory illnesses such as asthma and a greater incidence of cardiovascular disease (Pope, Bates & Raizenne, 1995). Urban environments struggle heavily with air pollution due to the large amount of factories and vehicles that are major sources of air pollutants that accumulate so much that they become a hazard to human health. In Canada, the Ontario Medical Association found air pollution to result in 9,500 premature deaths per year (OMA, 2008) and estimates increased costs of healthcare up to $506.64 million and lost productivity of up to $374.18 as a result of air pollution (OMA, 2005). Conditions will only worsen as pollution grows with population, traffic, industrialization and energy use (Mayer, 1999). There are many pollutants in the air of an urban environment, though particulate matter (PM10), ozone (O?), sulfur dioxide (SO?), and nitrogen dioxide (NO?) are among the most serious to human health (World Health Organization, 2016).

Particulate matter that appears in urban environments is made up of sulfate, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water that exist in the air from human activities such as combustion of fossil fuels, vehicles, and factory emissions. According to The World Health Organization (WHO), the limit for PM10 is 50 ?g/m3 annual mean. This represents how much particulate matter is allowed in the air annually by law. Chronic exposure to particles contributes to the risk of developing cardiovascular, respiratory diseases, and lung cancer (WHO, 2017).  In countries of Europe that have concentrations of PM above guideline levels, it is estimated that average life expectancy is 8.6 months lower than it would be if PM exposure from human sources was regulated (WHO, 2017).

NO2 is most commonly formed from anthropogenic burning of fuel (heating, power generation, and engines in vehicles/ships). The limit for nitrogen dioxide is 40 ?g/m3 annual mean. Epidemiological studies have shown that symptoms of bronchitis in asthmatic children increased in association with long-term exposure to NO2 and at short-term concentrations above 200 ?g/m3, NO2 is a toxic gas which causes significant inflammation of the airways (WHO, 2017). Reduced lung function growth is also linked to NO2 at higher concentrations currently measured in Europe and the US. The US EPA (1998) also focuses on the danger of NO2 by stating that Nitrogen oxides (NOx) resulting from combustion of fossil fuels can form ground level ozone that causes respiratory problems, premature deaths, and reductions in crop yields. (EPA, 1998).

Ozone at ground level, not to be confused with the ozone layer in the upper atmosphere, is formed from vehicle and factory emissions and emissions from solvents and industry. The legal amount that is allowed in cities is 100 ?g/m3 8-hour mean, which means that by law over 8 hours concentrations of ozone cannot exceed 100 ?g per cubic meter of air. In some cases, chemicals like nitrogen oxides (NOx) react with sunlight and also contribute to forms of ozone. The limit for ozone is 100 ?g/m3 8-hour mean and once this threshold is passed, O3 can cause breathing problems, trigger asthma, reduce lung function and cause lung diseases (WHO, 2017). The American Lung Association (2007) reported that annually, over 3,700 premature deaths in the United States (premature death is a death that occurs before a person reaches their expected age) can occur as a result of a 10 parts per billion (ppb) increase in O3 levels (ALA, 2007). Bell (2004) found that increased mortality rates in 95 urban areas within the US are linked to elevated levels in ozone, with one of these urban areas being Chicago, where ALA (2007) found over 2 million people at increased risk for health problems resulting from short-term exposure to O3 and particulate matters (ALA, 2007; Bell, 2004).

SO2 is a colourless gas with a sharp odour that is produced from the burning of sulfur-containing fossil fuels (coal/oil) for heating residences, generating power, and motor vehicles along with the smelting (extraction by melting) of mineral ores that contain sulfur. The limit for sulfur dioxide is 20 ?g/m3 24-hour mean and this means that air in cities will contain on average 20 ?g per cubic meter over the span of 24 hours. When the limit is exceeded, SO2 can affect the respiratory system, lung functioning, and cause irritated eyes. Evidence shows that the effects of sulfur dioxide are felt very quickly and most people would feel the worst symptoms of coughing, wheezing, shortness of breath, or a tight feeling around the chest in 10 or 15 minutes after breathing it in (S02, 2005). Inflammation of the respiratory tract causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis and makes people more prone to infections of the respiratory tract (WHO, 2017).

One policy the U.S. government has in place to control pollution levels is the Clean Air Act (CAA) of 1970 (majorly revised in 1977 and 1990). The CAA’s purpose is to reduce air pollution and its harmful effects by setting limits on pollution. This Act requires states to meet specific air quality standards regarding six common pollutants: particulate matter, ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead (EPA, 2017b). The Act contains specific provisions to address hazardous or toxic air pollutants, acid rain, chemical emissions that deplete the ozone layer, and regional haze (EPA, 2017b). The six “criteria” air pollutants are regulated based primarily on human health and secondarily on environmental criteria.

The CAA improved the environment which in turn improved the economy and human health. In the 45 years following the installation of the CAA, national emissions of the six common pollutants dropped an average of 70% while gross domestic product grew by 246% (EPA, 2017c). Forty-one areas that previously had unhealthy carbon monoxide levels in 1991 now meet the health-based national air quality standard. In 1990 alone, pollution reductions under the Act prevented 205,000 early deaths, 10.4 million lost I.Q. points in children due to lead exposure, and a multitude of other health effects (Environmental Protection Agency, 2017d). Despite massive improvements in air quality since CAA took effect, millions of Americans still live in areas with pollution levels exceeding the limits (EPA, 2007). Those who struggle to meet CAA air quality standards may find green roofs a useful tool to bring pollutant levels down.

In response to rising air pollutants, people are considering transforming city rooftops into green roofs to mitigate the problem. A green roof is a layer of vegetation installed on top of a roof, either flat or slightly sloped (National Park Service, 2017). The high amount of rooftop space in urban cities creates an opportunity for green roofs to be implemented on a large scale. Roofs represent 21–26% of urban areas and 40–50% of their impermeable areas (Wong, 2005; Dunnett & Kingsbury, 2004). These spaces typically have much unused surface area that could be repurposed to combat the aforementioned effects of harmful air pollutants, a green roof’s main purpose. The plants that compose the roof are able to take up compounds through their natural processes respiration and photosynthesis, which remove the pollutants from the air and improve its quality.WHO has guidelines for the limits of the primary air pollutants that must not be exceeded in urban environments. Green roofs will help keep the levels of PM10 at 50 ?g/m3 annual mean, nitrogen dioxide at 40 ?g/m3 annual mean, ozone at 100 ?g/m3 8-hour mean, and the concentrations of sulfur dioxide in the air of urban environments at 20 ?g/m3 24-hour mean.

Literature surrounding green roofs agrees on their impact of particulate matter removal (Speak, Rothwell, Lindley & Smith, 2012; Currie & Bass, 2008; Rowe, 2011; City of Los Angeles, 2005; Yang, Yu & Gong, 2008; Jayasooriya, Ng, Muthukumaran & Perera, 2017). The range of particulate that is annually reduced by a green roof is 0.42–3.21 g/m2 over 500,000 square meters of rooftops (Speak et al, 2012). Rowe (2011) performed a study where 2000 m2 of uncut grass were planted on a green roof. It was estimated that the green roof could remove up to 4000 kg of particulate matter. In a simulation where green roofs were built over 198,000 square meters of roofs in Chicago, 234.5 kg of particulate matter would be removed by green roofs in one year (Yang et al., 2008).  Yang et. al (2008) also did a study where the concentrations of acidic gaseous pollutants and particulate matters on a 4000 m2 roof in Singapore are measured before and after the installation of a green roof. Research found that the levels of particulate matter was reduced by 6% in the air above the roof after installation of the green roof (Yang et al., 2008). Jayasooriya et al. (2017) state that green roofs annually remove 1.53 g/m2 PM10  (Jayasooriya et al., 2017).Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of PM10 by .89–9.21 g/m2 (grams per square meter) over 486,000-2,430,000 square meters of green roof coverage in Toronto (Currie & Bass, 2008). Jayasooriya et al. (2017) states that green roofs annually remove 1.53 g/m2 PM10 (Jayasooriya et al., 2017). Another study on green roof remediation in Los Angeles (LA) puts these numbers of removed particulate matter into context. The city of LA found one square meter of green roof able to remove approximately 0.1 kg of particulate matter per year and if a gasoline powered vehicle were to release .01 grams of pm per mile of travel and drive 10,000 miles per year, then the vehicle would emit 100 grams per year (.01 kg/year) and therefore, one square foot of green roof would reduce the pollution of this theoretical car for the whole year (City of Los Angeles, 2005). According to the literature, the annual range of particulate matter reduced by green roofs fall between .42 g/m2 and 9.21 g/m2 (Speak et al., 2012; Currie & Bass, 2008; Rowe, 2011; City of Los Angeles, 2005; Yang et al., 2008; Jayasooriya et al., 2017).

Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of NO2 by 0.6–2.55 g/m2. Yang et. al (2008) found that if green roofs were built over 198,000 square meters of roofs in Chicago, 452.25 kg of nitrogen dioxide would be removed by green roofs in one year. Rosenfeld, Akbari, Romm, and Pomerantz (2008) calculated that emissions from coal fired power plants to the air could be reduced by 350 tons of NOx per day in Los Angeles by implementing green roofs. This value of energy saved from the installation of green roofs relates to a 10% reduction in the causes of smog to the city of Los Angeles, with an active NOx trade program, and results in a savings of one million dollars per day (Akbari, Pomerantz & Taha, 2001; Rosenfeld et al.,1998;  Clark, Talbot, Bulkley & Adriaens, 2005) estimate that if 20% of all industrial and commercial roof surfaces in Detroit, MI, were traditional extensive sedum green roofs, over 800,000 kg per year of NO2 , 0.5% of that area’s emissions, can be removed. Yang et. al (2008) states that green roofs annually remove 2.33–3.57 g/m2, NO2 in an urban environment. Jayasooriya et al. (2017) states that green roofs annually remove .37 g/m2 NO2. In a study done in Singapore, 21% of nitrous acid, a byproduct of nitrogen dioxide, was reduced directly above a green roof (Rowe, 2011). One study implementing green roofs in Kansas City, MO, used by the EPA, estimated that by 2020, green roofs would reduce 1800 pounds (816 kg) of NOx (EPA, 2016). After reviewing the literature, it is found that a green roof can reduce a range of 0.37-3.57 g/m2 (Currie & Bass, 2008; Yang et. al., 2008; Jayasooriya et al., 2017; Rosenfeld et al., 2008) Clark, Adriaens, and Talbot (2008) reported that green roofs yield an annual benefit of $0.45–$1.70 per m2 ($0.04–$0.16 per square foot) in terms of nitrogen oxide uptake. Clark et al. (2005) estimates that NOx reduction from a 2000 ft2 green roof would provide an annual benefit of $895–$3392, resulting in the green roof being 24.5-40.2% cheaper than a conventional roof without vegetation.

Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of O3 by 1.2–3.58 g/m2. Yang et al. (2008) state green roofs have the potential to annually reduce 4.49–7.17 g/m2 O3 and in their simulation of Chicago, green roofs were built over 198,000 square meters of roofs, the results were measured over the course of just one year, with 871 kg of O3 removed by green roofs. Jayasooriya et al. (2017) state that green roofs annually remove 1.24 g/m2 O3 . Since ozone is formed by the reaction of sunlight with pollutants such as nitrogen oxides (NOx), green house reduction in nitrogen oxides also reduce concentrations of ozone in the urban environment. According to the literature, the annual range of ozone reduced by green roofs fall between 1.2 g/m2 and and 7.17 g/m2 (Currie & Bass, 2008; Yang et. al., 2008; Jayasooriya et al., 2017).

Yang et. al (2008) found that if green roofs were built over 198,000 square meters of roofs in Chicago, 117.25 kg of sulfur dioxide would be removed by green roofs in one year. Currie and Bass (2008) state that green roofs have the potential to reduce annual amounts of SO2 by 0.2–0.84 g/m2. Yang et al. (2008) state that green roofs annually remove 0.65–1.01 g/m2 SO2. Jayasooriya et al. (2017) state that green roofs annually remove 0.1 g/m2 SO2. In a study done in Singapore, 37% of sulfur dioxide was reduced directly above a green roof (Rowe, 2011). One study implementing green roofs in Kansas City, MO, used by the EPA, estimated that by 2020, green roofs would reduce 2600 pounds (1179.34 kg ) of SO2 (EPA, 2016). In one field study, the concentrations of acidic gaseous pollutants and particulate matters on a 4000 m2 roof in Singapore are measured before and after the installation of a green roof. Research found that the levels of SO2 were reduced by 37% in the air above the roof after installation of the green roof (Yang et al., 2008). After reviewing the literature, it is found that a green roof can reduce a range of 0.10-1.01 g/m2 (Currie & Bass, 2008; Yang et al., 2008; Jayasooriya et al., 2017; Rowe, 2011, EPA, 2016)

As an example of the costs of building a green roof in a U.S. city, the installation costs to install green roofs on every roof in Chicago were estimated to be $35.2 billion (Yang et al., 2008). This brings up a high cost of green roofs that deters many cities from considering installation. The EPA projected in 2009 that extensive green roof installation costs, which were ranging from $15-$20/sq. foot should drop to $8-$15/sq. foot as installations increased, and soil substrate and plants became more available (EPA, 2009). Not everyone considers green roofs for their own homes, however, with the amount of pollution removed and human health improvements and the inherent existent pollution in cities, green roofs are critical to pollution removal in urban environments and should therefore be installed. In fact, having a green roof reduces more pollution in an urban environment than simply not having one at all. Agra, Klein, Vasl, Kadas, and Blaustein (2017) compared green roofs to other roofs of buildings with no vegetation at all (control roofs) and found that the control roofs had a CO2 concentration 50 cm above the ground of almost 375 ppm while the three types of green roofs in the study ranged from maintaining concentrations of 365-370 ppm of CO2 50 centimeters above surface (Figure 1). With green roofs being confirmed to be more effective With costs of green roofs accounted for and their associated improvement of human health via reduction in air pollution, green roofs can become even more desirable with the inclusion of governmental incentives/policies for cost reduction.

Seeing cost as one of the main obstacles standing in the way of green roofs, we urge government action to alleviate this issue. The U.S. government must make green roof installation less expensive through an incentive system. Funding should be granted to all major U.S. cities for the installation of green roofs. Depending on design, plant type, and climate conditions the price of green roof construction typically ranges from $15-20 per square foot, though the EPA projects that extensive green roof installation costs should drop to $8-$15/sq. foot as installations increase, and soil substrate and plants became more available (EPA, 2009). The U.S. Government should offer $10 per square foot of green roof for commercial, residential, and private properties. In target areas where pollution is most concentrated, the government should offer $15 per square foot. This proposal makes the initial up-front cost of green roofs more feasible, if not directly profitable.

Green roofs become more attainable and widespread with the help of government incentives, as shown by successful policies in Washington D.C. Currently, Washington D.C. has over 3 million square feet of green roof (Department of Energy & Environment, 2017a). The district set a goal that by 2020, 20% of its buildings will have green roofs. In 2006, the D.C. Department of Energy and Environment (DOEE) launched the “RiverSmart Rooftops Green Roof Rebate Program” to give grants that encourage the installation of green roofs on private property. The grants offer $10 per square foot and up to $15 per square foot if the building is in target watersheds. With no cap on project size, all properties are eligible including residential buildings. To encourage small buildings to install green roofs as well, the program gives funds to offset costs of structural assessments to buildings of under 2,500 square feet (DOEE, 2017a). This incentive plays a large role in the growth in green roof installation per year in D.C. In 2005, building owners installed 0 square feet of green roof as compared to 104,068 sq feet of green roof installed in 2006, the first year of this initiative (DOEE, 2017b). In 2015, D.C. implemented a whopping 712,493 square feet of green roof. Though there is some variation, there is a general increase in total green roof area in Washington D.C. (DOEE, 2017c). An incentive program similar to this on the federal level would increase the total area of green roofs on a broader scale.

Installing green roofs in urban environments is cost-effective. They reduce the amount of pollution in air, improve the health of people living in urban cities, and can be less expensive to install with the implementation of governmental incentives & policies. If all rooftops in Chicago were covered with intensive green roofs, a projected 2046.89 metric tons of pollutants would be removed (Yang et al., 2008).

When discussing the green roofs ability to improve human health, the concentrations of pollutants most commonly discussed in the literature are O3, SO2, particulate matter, and NOx   (Agra, 2017; Clark et al., 2005, 2008; Rowe, 2011; City of Los Angeles, 2006; Rosenfeld, 1998; EPA, 1998) By installing green roofs, the four main pollutants would decrease in concentration enough to create improvements in human health and economic benefits in the reduction of human mortality.  Worker productivity and health is improved along the way, as employees that have a view of nature scenery were less stressed, had lower blood pressure, reported fewer illnesses, and experienced greater job satisfaction (Kaplan et al., 1988; Ulrich, 1984).

The cost-benefit analyses discussed how implementing green roofs would result in savings of a million dollars a day from decreased air conditioning, an overall annual benefit of $895–3392 for each 2000 ft2 green roof, and a reduction in the particulate emissions of one car for a whole year per square meter of green roof. Green roof financial incentives in Washington D.C. greatly increased the total area of green roofs in the area (DOEE, 2017b). An incentive program paired with indirect incentives would be successful if emulated on a federal level. The U.S. has proven that federal environmental policies can be effective as show by the Clean Air Act (EPA, 2015).

Even though green roofs cost 2-3 times as much as a bare roof to install, government incentives can alleviate these costs to bring installation prices down. With the upfront costs lowered, we can reap the benefits of financial, health, and environmental pay-off by green roofs.

AUTHORS

Matas Rudzinskas – Environmental Science

Aaron Lutz – Turf Grass Science

Tara McElhinney- Natural Resource Conservation

 

REFERENCES

Agra, H., Klein, T., Vasl, A., Kadas, G., & Blaustein, L. (2017). Measuring the effect of plant-community composition on carbon fixation on green roofs. Urban Forestry & Urban Greening, 24, 1-4. doi:10.1016/j.ufug.2017.03.003

Akbari, H., Pomerantz, M., & Taha, H. (2001). Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas. Solar Energy, 70(3), 295-310. doi:10.1016/s0038-092x(00)00089-x

Australian government, Department of the Environment and Energy (2005). Sulfur dioxide (SO2). http://www.environment.gov.au/protection/publications/factsheet-sulfur-dioxide-so2

Bell, M. L. (2004). Ozone and Short-term Mortality in 95 US Urban Communities, 1987-2000. Jama, 292(19), 2372. doi:10.1001/jama.292.19.2372

City of Los Angeles Environmental Affairs Department. 2006. Report: Green roofs – cooling Los Angeles

Clark, C., Adriaens, P., & Talbot, F. B. (2008). Green Roof Valuation: A Probabilistic Economic Analysis of Environmental Benefits. Environmental Science & Technology, 42(6), 2155-2161. doi:10.1021/es0706652

Clark, C., Talbot, F.B., Bulkley, J., & Adriaens, P.. (2005). Optimization of green roofs for air pollution mitigation Proc. of 3rd North American Green Roof Conference: Greening Rooftops for Sustainable Communities, Washington, DC. 4–6 May 2005, The Cardinal Group, Toronto (2005)

Currie, B. A., & Bass, B. (2008). Estimates of air pollution mitigation with green plants and green roofs using the UFORE model. Urban Ecosystems, 11(4), 409-422. doi:10.1007/s11252-008-0054-y

Department of Energy and Environment. (2017a). [Graph of green roof installation (in sq ft) per year in Washington D.C. from years 2001-2017]. Green Roof Installation. Retrieved from https://doee.dc.gov/publication/inventory-green-roofs

Department of Energy and Environment. (2017b). Green roofs in the District of Columbia. Retrieved from https://doee.dc.gov/greenroofs

Department of Energy and Environment. (2017c, November). Green roofs in the District of Columbia November 2017. Retrieved from https://doee.dc.gov/sites/default/files/dc/sites/ddoe/publication/attachments/2017.11%20GREEN%20ROOFS%20IN%20THE%20DISTRICT%20OF%20COLUMBIA.pdf

Department of Energy and Environment. (2017d). RiverSmart rewards and clean rivers IAC incentive programs. Retrieved from https://doee.dc.gov/greenroofs

Department of Energy and Environment. (2017e). Stormwater retention credit trading program. Retrieved from https://doee.dc.gov/src

Dunnett, N., & Kingsbury, N. (2010). Planting green roofs and living walls. Portland: Timber Press.

Environmental Protection Agency. (2007). The Plain English Guide To The Clean Air Act https://www.epa.gov/sites/production/files/2015-08/documents/peg.pdf

Environmental Protection Agency. (2015). Progress cleaning the air and improving people’s health. Retrieved from https://www.epa.gov/clean-air-act-overview/progress-cleaning-air-and-improving-peoples-health

Environmental Protection Agency. (2016).

https://www.epa.gov/sites/production/files/2016-10/documents/webinar.gi_.robyn3__1.pdf

Environmental Protection Agency. (2017a). Benefits and costs of the clean air act, 1970 to 1990 – Study design and summary of results. Retrieved from https://www.epa.gov/clean-air-act-overview/benefits-and-costs-clean-air-act-1970-1990-study-design-and-summary-results

Environmental Protection Agency. (2017b). Clean air act requirements and history. Retrieved from https://www.epa.gov/clean-air-act-overview/clean-air-act-requirements-and-history

Environmental Protection Agency. (2017c). Progress cleaning the air and improving people’s health. Retrieved from https://www.epa.gov/clean-air-act-overview/progress-cleaning-air-and-improving-peoples-health#pollution

How healthy is the air you breathe? (American Lung Association). Retrieved November 13, 2017, from http://www.lung.org/our-initiatives/healthy-air/sota/

Jayasooriya, V., Ng, A., Muthukumaran, S., & Perera, B. (2017). Green infrastructure practices for improvement of urban air quality. Urban Forestry & Urban Greening, 21, 34-47. doi:10.1016/j.ufug.2016.11.007

Kampa, M., & Castanas, E. (2008). Human health effects of air pollution. Environmental Pollution, 151(2), 362-367. doi:10.1016/j.envpol.2007.06.012

Mayer, H. (1999). Air pollution in cities. Atmospheric Environment, 33(24-25), 4029-4037. doi:10.1016/s1352-2310(99)00144-2

National Park Service (2017). What is a Green Roof—Technical Preservation Services, https://www.nps.gov/tps/sustainability/new-technology/green-roofs/define.htm.

Ontario Medical Association (2005) Illness Costs of Air Pollution  www.oma.org/Resources/Documents/2005IllnessCostsofAirPollution.pdf

Ontario Medical Association (2008) Ontario’s Doctors: Thousands of Premature Deaths Due to Smog (2008) www.oma.orf/Mediaroom/PressReleases/Pages/PrematureDeaths.aspx

Pope, C. A., Bates, D. V., & Raizenne, M. E. (1995). Health Effects of Particulate Air Pollution: Time for Reassessment? Environmental Health Perspectives, 103(5), 472. doi:10.2307/3432586

Rosenfeld, A. H., Akbari, H., Romm, J. J., & Pomerantz, M. (1998). Cool communities: strategies for heat island mitigation and smog reduction. Energy and Buildings, 28(1), 51-62. doi:10.1016/s0378-7788(97)00063-7

Rowe, D. B. (2011). Green roofs as a means of pollution abatement. Environmental Pollution, 159(8-9), 2100-2110. doi:10.1016/j.envpol.2010.10.029

Speak, A., Rothwell, J., Lindley, S., & Smith, C. (2012). Urban particulate pollution reduction by four species of green roof vegetation in a UK city. Atmospheric Environment, 61, 283-293. doi:10.1016/j.atmosenv.2012.07.043

Ulrich, R. (1984). View through a window may influence recovery from surgery. Science, 224(4647), 420-421. doi:10.1126/science.6143402

United States General Services Administration (2011). The Benefits and Challenges of Green Roofs on Public and Commercial Buildings. https://app_gsagov_prod_rdcgwaajp7wr.s3.amazonaws.com/The_Benefits_and_Challenges_of_Green_Roofs_on_Public_and_Commercial_Buildings.pdf

WHO 2016 (World health organization) – Ambient (outdoor) air quality and health. (2016). Retrieved November 14, 2017, from http://www.who.int/mediacentre/factsheets/fs313/en/

Wong (2005) Green roofs and the Environmental Protection Agency’s heat island reduction initiative Proc. of 3rd North American Green Roof Conference: Greening Rooftops for Sustainable Communities, Washington, DC. 4–6 May 2005, The Cardinal Group, Toronto

Yang, J., Yu, Q., & Gong, P. (2008). Quantifying air pollution removal by green roofs in Chicago. Atmospheric Environment,42(31),7266-7273.doi:10.1016/j.atmosenv.2008.07.003

 

 

What the Frack? Fracking Threatens the Environment With Methane Leakage

Evan 13 Comments

(University of Michigan, 2013)

Wellsboro, a rural Pennsylvania town of roughly 3,200 residents, wasn’t doing very well economically (Hurdle 2010). Local farms were heavily in debt, motels frequently had occupancy under 40% outside of the tourism season, and many residents earned $12,000 less each year than the state average (Hurdle 2010). All of that started to change in 2008, when farmers started to receive checks of $375,000 or more, catapulting them back into financial solvency (Hurdle 2010). Then the railroad started to pick up, breaking out of more than 20 years of stagnation and doubling its yearly revenue (Hurdle 2010). Following the increase in rail traffic was a similar increase in traffic on the roads, so much so that residents were concerned the roads wouldn’t be able to take it (Hurdle 2010). Motels regularly filled up during the normally quiet winter and other businesses saw a similar increase in customers (Hurdle 2010). What could have caused an economically insignificant town like Wellsboro to experience such a reversal of fortunes? The answer was simple: fracking.

“Fracking”, a common nickname for hydraulic fracturing, is a relatively new form of unconventional gas production (EPA 2017). By injecting a solution of water and various additives into a wellbore at high pressure, surrounding rock formations are fractured, allowing trapped oil or natural gas to escape (EPA 2017, Allen et al., 2013, p. 17768). Once the initial injection is complete, the naturally pressurized gas flows back to the wellbore (EPA 2017). With the gas comes some of the injected fluid, which may now contain naturally occurring materials such as brines, metals, radionuclides, and hydrocarbons (EPA 2017). This returning liquid is known as “flowback”, and is a waste product that is collected for recycling or disposal (EPA 2017). The flowback is contained to prevent the aforementioned materials and some of the methane gas from escaping into the environment (Allen et al., 2013, p. 17769). After the flowback is dealt with, the natural gas escaping from the wellbore can be captured and later sold. Fracking has allowed the extraction of gas from previously inaccessible rock formations such as tight sandstone, shale, and some coal beds (EPA 2017). Wellbores can be vertically drilled hundreds or thousands of feet underground, and can include additional horizontal drillings that extend thousands of feet to help reach the gas dispersed throughout the rock formations (EPA 2017).

Fracking is only a problem insofar as it is an imperfect solution to a larger issue. That larger issue is how to generate energy without further increasing our contribution to climate change. This desire for cleaner fuel sources has made natural gas more attractive, and the increased demand has been met by wider use of fracking. The demand is so great that 91 to 273 additional wells have to be drilled every year just to maintain current production of natural gas (Stephenson et al., 2011, p. 10760). The economic and environmental benefits provided by fracking have been the driving force behind the increased popularity of fracking.

Fracking provides many two main economic benefits: creating jobs and economically producing natural gas. From 2007 to 2012, employment in the U.S. private sector grew by a measly 1%, while the oil and natural gas sector grew by a whopping 40% (U.S. EIA, 2013). This amounted to a total of 725,000 jobs nationwide, cutting unemployment by half a percent during the recession (Reuters, 2015). Most of these jobs were created near where the gas was extracted, at a rate of roughly 2.5 jobs per million dollars of gas extracted (Reuters, 2015). The majority of these jobs were within 100 miles of new natural gas production, with some directly involved in producing the gas, and some indirectly assisting (Reuters, 2015, U.S. EIA, 2013). Jobs for drilling wells increased only marginally, with most of the overall increase being in the areas of extraction and support (U.S. EIA, 2013). As shown by the data, fracking has a significant impact on employment, making it a promising source of energy.

The increased production of natural gas caused by fracking has had many positive economic effects. One of the most stunning effects is that the U.S. now produces 97% of its natural gas needs (U.S. EIA, 2017). This has resulted in net imports of natural gas declining by roughly 3 trillion cubic feet from 2005 to 2016 (U.S. EIA, 2017). In fact, the U.S. is expected to export as much as 7 trillion cubic feet of natural gas per year by 2025 (Sieminski, 2014). For now, the natural gas produced by the U.S. is used domestically, mostly for power generation and in the industrial sector (Sieminski, 2014). This is particularly visible in the Northeastern United States, where electricity generation from natural gas has increased by more than 10 million kWh in Pennsylvania, New York, and New Jersey (U.S. EIA, 2017). With domestic natural gas prices in 2017 being almost universally lower than they were in 2011 (U.S. EIA, 2017), it’s only logical that bulk users of fuel like power plants would switch to take advantage of the sudden windfall. While normally the decrease in operating costs for power plants caused by fracking would be solely of benefit to the economy, this also benefits the environment.

Prices of natural gas in the U.S. are heavily dependent on how much gas can be extracted from shale formations economically (U.S. EIA, 2012). In 2005, near the start of the fracking boom, natural gas prices began to decline rapidly (U.S. EIA, 2012). This trend continued into 2016, with prices plummeting to half of what they were in 2011 (U.S. EIA, 2012). There can be no doubt that fracking is responsible for the current glut of natural gas, with two locations exemplifying this; The Barnett shale in Texas and the Marcellus shale in the Northeast United States. The trends in these areas are mirrored across the U.S., with natural gas from shale and tight formations making up at least 50% of national natural gas production in 2010 (Sieminski, 2014). In Texas horizontal drilling in the Barnett shale has exploded from less than 400 wells in 2004 to over 10,000 by 2010 (U.S. EIA, 2011). These horizontal wells are responsible for roughly 90% of the natural gas production of the entire Barnett shale, despite only making up 70% of productive wells in the region (U.S. EIA, 2011). In the Northeast U.S. the Marcellus shale has provided so much cheap gas that power plants have increased their use of natural gas by 20%, making natural gas responsible for 41% of power generation in the region by 2016 (U.S. EIA, 2017). This has mostly come at the expense of coal, which in New York and Connecticut has seen a 90% decline from 2006 levels (U.S. EIA, 2017). In addition to the increased availability of natural gas, environmental policies such as tax credits and mandates to reduce CO2 emissions have made natural gas increasingly attractive compared to coal (U.S. EIA, 2017). Despite prices in 2012 being 30% lower than the previous year, the only coal that increased in production was high-sulfur coal that is compatible with CO2 reducing scrubbers (U.S. EIA, 2013). Similarly, in 2012 cheap natural gas was so abundant that carbon dioxide emissions from coal burned for power generation decreased to levels not seen since 1984 (U.S. EIA, 2013). While electricity sales declined by only 1% nationally from 2006 to 2016, total CO2 emissions from energy generation fell by roughly 10% (U.S. EIA, 2013, U.S. EIA, 2017). This is due to the fact that the main component of natural gas is methane (CH4) (Teasdale et al., 2014), and methane releases roughly 50% as much carbon as coal when burned (U.S. EIA, 2017). By replacing carbon intensive coal with cleaner natural gas in the energy sector, less total carbon has been emitted despite overall production remaining roughly the same (U.S. EIA, 2013, U.S. EIA, 2017). In 2015 when emissions from coal and natural gas in the energy sector were nearly equal, natural gas produced 80% more electricity than coal, clearly cementing natural gas as the less carbon intense fuel (U.S. EIA, 2017). By providing more energy at a similar or even lesser cost to coal, natural gas is paving the way for an energy-secure future with less carbon emissions.

While natural gas has been shown to cause less carbon dioxide emissions than the coal it is replacing, it brings with it a new problem, that of methane leakage.  Methane emissions are a concern because methane is a particularly potent greenhouse gas.  Greenhouse gases are gases that trap heat in the atmosphere, contributing to climate change. The overall impact each gas has on global climate change depends on the the amount of time it stays in the atmosphere, overall quantity of it in the atmosphere, and how strongly it absorbs energy (EPA, 2017). Using these factors, greenhouse gases are compared using a unit of measurement known as the Global Warming Potential (GWP) (Forster, 2007., p. 210). GWP is standardized to be comparative to carbon dioxide, so a gas with a GWP of 2 has twice the effects of an identical amount of carbon dioxide when released into the atmosphere (Forster, 2007., p. 210). The GWP of methane is 72 for a period of 20 years, and 21-25 for a period of 100 years (Forster, 2007., p. 212), so we can see it has a much larger impact on trapping heat than carbon dioxide. While methane only has a lifetime of 12 years, the indirect effects it can have on other compounds allow it to do damage long after its initial release (Forster, 2007., p. 212). With natural gas and petroleum systems making up the largest energy-related methane emissions source in the U.S., something needs to be done to control their emissions (EPA, 2017).  

For overall emissions coming from fracking, Allen et al. (2013) found that natural gas production emits about 2.3×1012 grams of methane, which comprises of 0.42% of gross gas production (Allen et al., 2013, p. 17772).  Of the total emissions, Omara et al. (2016) compared methane emission rates from conventional (vertical drilling for reservoirs that have high permeability) and unconventional (horizontal drilling for low-permeability sources, such as shale) natural gas extraction wells.  The authors found that unconventional wells (850 to 9.29×104 g/h) generally emitted higher amounts of CH4 than conventional wells (20 to 4480 kg/h) (Omara et al., 2016, 2102).  Considering natural gas’s comparatively massive GWP, total leakage from fracking systems must be less than 3.2% to have net environmental benefits over coal, a notoriously dirty fuel (Alvarez et al., 2012, p. 6437). Consensus in scientific literature shows that fracking in the United States has leakage rates between 3% and 17%, meaning we have likely already passed the point where natural gas provides benefits (Caulton et al., 2015, pg. 6240, Jiang et al., 2011, p. 7, Karion et al., 2013, p. 4396).  Coupling the rise in demand of fracking with the rapid decrease of well productivity after the first year (Stephenson et al., 2011, p. 10760), new wells are constantly needing to be drilled.  This means methane emissions from fracking will continue to increase, and we will continue to stray further from the environmental benefits fracking was originally thought to have if nothing is done about these emissions (Schneising et al., 2014).

Fracking can be broken into four phases: pre-production, drilling, fracturing, and well completion (Jiang et al., 2011).  Of all the stages, well completion has the greatest methane emissions.  During this process, methane can be emitted through flowback, the recovery of the liquids, if it is not sent to emission control devices (Allen et al., 2013, p. 17769).  Allen et al. (2013) measured a range of about 1.0×104 grams to 1.7×107 grams in methane emissions, with a mean of 1.7×106 grams.  Emissions this high should be addressed.

Further compounding the problem is the fact that inventory estimates of methane leaks are almost universally undervalued (Goetz et al., 2015, Caulton et al. 2015). This is partially due to the difficulty of locating the sources of these leaks (Teasdale et al., 2014). Having official estimates of leakage rates chronically lower than actual rates presents a false picture to the public, making continued fracking seem more viable than it may actually be. More than with almost any other energy source, accurately measuring leak rates and continuously working to reduce them is a critical part of making fracking an economically and environmentally viable energy source. Because of these higher emissions, many environmentalists believe fracking should be gotten rid of altogether.  However, as mentioned previously, when fracking is done right with technology controlling its methane emissions, it has the potential to be a more environmentally friendly source of energy than coal by emitting less carbon dioxide (U.S. EIA, 2013, U.S. EIA, 2017).  This, and the fact that it provides jobs (Reuters, 2015, U.S. EIA, 2013) and lowers the cost of natural gas (U.S. EIA, 2012) is enough reason as to why we should not disregard fracking.

There needs to be solution to fracking’s methane emissions, so that it can meet its potential as an energy source.  Allen et al. (2013) measured methane emissions significantly lower than the EPA’s measurements from the national emissions inventory because 67% of the wells that were in the study sent methane to control devices rather than releasing it to the atmosphere, which brought their emissions significantly down (p. 17770).  One of the most efficient methods to stop the problem of methane leakage from a fracking site is the vapor recovery unit, better known as VRU. VRUs work with the storage tanks, which store emissions from flowback, on a franking site. Storage tanks on fracking sites without VRUs vent approximately 21 billion cubic feet of gas per year (Harvey, 2012). The storage tanks are used to store the natural gas that has been collected throughout the fracking process. VRUs work to remove methane vapors that build up in the tank. Without VRUs methane can be get lost in the atmosphere when the gas is added to the tank, and when the gas is being removed from the tank (Harvey, 2012). The VRU system works by analyzing the pressure in the tank and when it reaches a set point the gas goes through a gas vent line and into the VRU machine .Within the VRU machine the gas is filtered through a scrubber where the liquid trapped is returned to the liquid pipeline system or to the tanks, and the methane recovered is pumped into gas lines (Changnet, 2008).

VRUs may be the answer to the methane leakage problem, as they can capture up to 95% of methane that would have leaked into the atmosphere from the storage tanks of a fracking site that does not use one (Harvey, 2012). The gas company Encana has a site in Wyoming that installed a VRU in order to reduce methane emissions. The VRU machine has shown to reduce 80% emissions in the past four years (Sider, 2014).

Using this machine will not only reduce most of the methane released, it could also save gas companies thousands of dollars in the long run. The methane gas that is filtered into the VRU can potentially be harvested and used for profit.  Anadarko Petroleum Corporation reported that at peak capacity their VRU were able to capture 25 million cubic feet of gas per day. At this rate the company was able to make $18,262 off the VRU alone in one year (Harvey, 2012). Gas companies that are using VRU systems have reported that they have been extremely beneficial when it comes to the payback. The gas producing company ConocoPhilips had installed a VRU system onto 9 tank batteries on one of their sites. This in total cost the company $712,500, however it did not take long for that money to be worth the investment. In just four months the VRU were able to bring the company enough profit to refund this payment. After that every month the VRU brought the company $189,000 (Harvey, 2012).

In 1970, Congress passed the Clean Air Act of 1970, which mandates reductions in various harmful volatile organic compounds (VOC). The act covers many aspects of VOC emissions, but fracking sites continue to emit methane which is harmful to the environment. This brings us to our proposal. If the EPA implemented stricter regulations on methane emissions in the Clean Air Act, companies would be forced to adopt various technologies, VRUs being one of them, in order to meet EPA regulations. In turn, the nation could stay away from relying on coal while minimizing harm to the environment from fracking. Methane emissions from fracking are indeed an issue, and something needs to be done to reduce them.

Certain drilling sites in Montana, Colorado, and Utah have already adopted this technology (EPA, 2014). This is the result of competition between fracking companies who aim to make their sites less harmful to air quality (Biello, 2010). In fact, mandatory Stage I and Stage II vapor recovery systems are a direct result of the Clean Air Act. These systems can be found at gasoline dispensing facilities (GDF), known to all of us simply as the gas stations that dot various roadways. Whenever gasoline is transported or pumped from one container to another, VOCs naturally escape into the atmosphere. Since GDFs can be found in many locations, harmful amounts of VOCs can be emitted into the atmosphere due to the frequency of oil tankers delivering fuel to GDFs and consumers refueling their automobiles. Stage I vapor recovery systems refer to when oil tankers deliver gasoline to various GDFs, and Stage II refers to when consumers refuel their automobiles. When consumers refuel their automobiles at GDFs, VOCs that would normally escape into the atmosphere are returned to the underground gas reservoirs at these GDFs. When oil tankers refill these reservoirs, the trapped VOCs are returned to the oil tankers (PEI, 2017). These regulations have invariably had an incredible impact on VOC emissions in the following years. The EPA shows that since 1970, VOC emissions have dropped from approximately 12 grams per vehicle mile travelled, to 2 (EPA, 2017). This shows that on a federal level, technology can be successfully and widely adopted in order to improve air quality at the expense of energy companies. If it can be done for petroleum, why can’t it be done for natural gas?

In order to reduce humanity’s impact on climate change, we should take the necessary steps to reduce GHG emissions.  While hydraulic fracturing is not the largest source of methane emissions, any chance to reduce emissions should be taken advantage of. There are a wide variety of ways one could reduce emissions from fracking, but not all of them are realistic. Flaring is already a common practice in the industry, but why burn off a useful gas when you can harness its potential? When a solution such as VRUs is readily available, why not utilize it?  They have a high efficiency of reducing emissions, and provide an opportunity for companies to profit from the captured methane.  We see VRUs already being implemented at certain sites across the country, and government-mandated implementation of vapor recovery technology is already present in gas stations, so it seems reasonable to do the same for fracking sites. And with the ever growing need for energy in our industry-driven world, and a steadily decreasing amount of natural gas, shouldn’t we harness all that we can, and protect our world while we’re at it?

AUTHORS

Hillary Wilcox – Animal Science Major

Mikhaela Flynn- Environmental Science Major

Sean Mulvaney – Natural Resource Conservation Major

Winsten Chen- Natural Resource Conservation Major

 

REFERENCES

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Alligator Gar As Means To Control Asian Carp

Evan 48 Comments

 

        Jordan Fielder, a nineteen year old boy, was enjoying a fun day on the Illinois river with his family when all of a sudden a large fish launched from the water like a missile, and smashed into his face. The fish fractured his nose, dented his forehead, and shattered bones in his eye sockets and brow (Schankman 2015). Jordan commented, “If it had hit me any harder it could have broken my skull bones and essentially damaged my brain and killed me on the spot”(Schankman 2015). For Jordan this was a fun family day on the river, turned to a near death experience. The fish responsible for this, is the invasive Asian carp, which is overrunning the Illinois river and its surrounding waters including the Mississippi, Missouri and Ohio rivers (Hayer et al. 2014). The carp easily become scared by boat motors or other loud noises which causes them to jump out of the water (Shankman 2015), turning their large bodies into a dangerous projectile which can clearly hurt people in their path. Jordan’s experience is not uncommon as this has happened to many others. As harmful as they can prove to humans, they are just as bad for the ecosystem, as is seen with many invasive species.

        In the 1950s, East Africans introduced Nile perch to Lake Victoria to strengthen a lacking fishing industry (Micalizio, 2015, p. 1). The environmental effects of this introduction completely transformed the Lake Victoria ecosystem. Voracious appetites and bountiful prey allowed the top-tier predator Nile perch to cause the extinctions of over 200-species of fish native only to Lake Victoria, such as cichlids. Native predatory catfish species such as the Sudan catfish and African sharptooth catfish also suffered as a result of the Nile perch (Frans Witte, 1997). In 1973, the Sudan catfish and African sharptooth had catch rates of 44 pounds per hour. However, by 1985 they had catch rates of zero. Whereas the Nile perch showed a catch rate of zero in 1973, but jumped to 176 pounds per hour by 1987, 4 times higher than the native catfish species when they were at peak abundance (p. 28). A domino-effect occurred from the loss of native species, leading to outbreaks of insects and algal blooms (Nile perch , 2014, p. 6). Some of the largest impacts came down on the backs of humans. The fishermen and their families cannot eat the fish themselves, they have too high a value and eating them means a loss in profits, yet fishermen go on longer fishing trips now than in the past to try and keep up with demand (p. 9). The Nile perch serve as an example that represents how non-native freshwater fish introductions can derail an ecosystem and community if not well-controlled or managed (Vitule et al., 2009). There is such an introduction happening right under our noses here in the United States, the invasive Asian carp.

        Ecosystems have a delicate balance in which organisms work in harmony, each occupying their own little niche (the role of an organism in an ecosystem) (Biology-online.org, 2016), when a new organism enters that ecosystem, they can occupy another species’ niche, competing with them for resources and food. Unfortunately, native species often lose this competition to the new invaders. The National Invasive Species Information Center (NISIC), defines invasive species as “non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health” (“What is an invasive species?” 2012, para. 1). One such invasive species, the Asian carp, have made a name for themselves here in the United States, introduced to control phytoplankton and for aquaculture.

        Native species of carp have existed in the United States for over 100 years, and the species called the “common carp” has lived here with little environmental impact (Naylor et al., 2001).  The newer and more potent Asian carp describe 4-different species, the bighead, grass, black, and silver carp. The U.S. imported silver and bighead carp in the 1970s from Asia for research purposes, putting them into wastewater lagoons and aquaculture ponds and observing if they improved water quality (Naylor et al., 2001, para. 2). Federal and state agencies, private citizens, and researchers imported and introduced the grass carp from eastern Asia in 1963 to control aquatic plants in fish farms (Grass carp, 2013, para. 1). Juvenile black carp came to the U.S., initially in Arkansas, in the 1970s when they arrived with a shipment of grass carp (Nico and Nielson, 2014). Nobody noticed because juvenile black and grass carp have nearly identical appearances. The U.S. attempted to use the black carp as a food resource and to control yellow grubs in aquaculture ponds (para. 5). Flooding events in aquaculture ponds connected to rivers allowed the silver, bighead, grass, and black carp to escape into the Mississippi River and Missouri River where they now have established breeding populations (Naylor et al., 2001, para. 2; Grass carp, 2013, para. 1; Nico and Nielson, 2014, para. 5).

        Invasive Asian carp demonstrate trends of rapidly increasing abundance a short time after their introduction. In the Missouri River in South Dakota, the abundance of Asian carp skyrocketed from 2009-2012 (Hayer et al., 2014, p. 294). In 2009, a fishing survey in the Missouri River caught no Asian carp. By 2012, fishing surveys caught 35 fish per hour (p. 294). In 6 sections of the Mississippi River, the number of Asian carp caught went from <50 per hour in 2003, to 775 per hour in 2012 after their introduction (Phelps et al., 2017, p. 7).  This 15x increase demonstrates the ability of Asian carp to overwhelm an area in as little as 9 years.

        Asian carp often outcompete native species for food (Asian carp overview, 2015). Asian carp filter feed and voraciously consume algae and zooplankton, primary food sources for native fish species like gizzard shad, paddlefish, and bigmouth buffalo (Asian carp overview, 2015; Irons et al., 2007; Sampson et al., 2009). Small zooplankton such as rotifers compose a large part of the diet of many native filter feeders, however, Asian carp consume them as well. In one section of the Mississippi River, Asian carp cut the abundance of rotifers from 6000 per liter of water in 2002, to 3500 in 2003, nearly a 50% decrease in only one year (Sampson et al., 2009, p. 488). Thus reducing the amount of available prey, and forcing predatory species to feast more heavily on other organisms such as copepods, seldom consumed by many fish, but compose nearly 62% of the diet of endangered paddlefish (p. 489). The decrease in rotifer abundance observed by Sampson et al. (2009) therefore means that fish will have to search for and eat different prey species instead of relying on rotifers the way they did before Asian carp.

        Asian carp reduce the abundance of native species where they colonize (Hayer et al., 2014; Phelps et al., 2017). In 2009, Asian carp represented <1% of the catch in the Missouri River, whereas the native emerald shiner fish comprised roughly 30% of fish caught in 2009. In 2012, Asian carp composed 50% of the catch, and emerald shiner dropped to 5% of the catch, equating to a 6x decrease in emerald shiner, and a 50x increase in Asian carp  (Hayer et al., 2014, p.298). In the Mississippi River, Asian carp caused the bigmouth buffalo population to decrease by 10%, instead of following the historically-observed increase of 35%. After the invasion of Asian carp, the number of buffalo caught per hour decreased from 178 to 85 (Solomon et al., 2016, p.8). In another study on the Illinois River, the bigmouth buffalo’s abundance declined by 80% in 2005, compared to the abundance recorded from fishing trips in 1995 (Irons et al., 2007, p. 268). In this same stretch of river, the annual Asian carp catch increased from 0 in 1995, to 500 in 2005 (p. 265)

        Predatory and game fish populations also undergo negative changes because before the young become large enough to eat other fish and crustaceans, they eat small plankton consumed by the invasive carp (Solomon et al., 2016, p.1). This means that if the carp kill off the young of a species, they will do massive damage to the species populations as a whole. For example, two species of crappie showed dramatic decreases in abundance, Black crappie populations decreased by 61.79% and white crappie populations decreased by 45.98% (Solomon et al., 2016, p. 8). Carp do not feed on crappie, but they feed on the same thing as the juveniles, causing the population to have trouble growing. The removal of plankton by Asian carp also casts residual effects on important prey species for predatory fish. For example Asian carp negatively affect gizzard shad, another filter feeder. These shad comprise an important food source for predators of the ecosystem (Phelps et al., 2017, p. 11). Shad are a staple food source of a very popular gamefish in the Largemouth Bass, if there are less shad, then the bass will not do as well (Storck et al. 2011, pg. 1). Gizzard shad went from an average biomass increase of 10% to nothing because the Asian carp reduced their survival rate from 80% to 10%, preventing their population from growing (Phelps et al., 2017, p.5). Fish catches also decreased by almost half for the shad going from 7186 per hour to 3810 per hour (Phelps et al., 2017, p.6). This massive decrease sends a negative effect right up the food chain of an ecosystem. Directly related to the shad population going down, the CPUE of Asian carp increased over the same period of time showing that the native fish get outcompeted (Phelps et al. 2017, p. 11). As carp became more prevalent in floodplain lakes, predators such as bass, catfish, gar and bowfin started to disappear. (Phelps et al. 2017, p.9).  

        One reason that carp have become so abundant is that native fish have shown a preference for native prey when given a choice between the two. Native piscivores of the Mississippi River Basin showed negative selectivity or preference of silver carp versus native prey species (Wolf et al. 2017, p. 1142). White bass tested in this study, chose Asian carp first only 3 of 29 times (Wolf et al., 2017, p. 1141). The study showed that largemouth bass chose to eat Asian carp first instead of native prey species only 4 of 29 times (Wolf et al., 2017, p. 1141). However largemouth bass did show a positive selection of 0.23 specifically for grass carp, however they still negatively selected for Asian carp in general with a -0.08 (Wolf et al., 2017, p. 1141).  In this study a score of 1 represented the highest selectivity for consuming Asian carp and a score of-1 represented a complete avoidance of Asian carp.  The study showed that all native piscivores showed little or no preference for Asian carp except the longnose gar, which had a selection for Asian carp of 0.12 (Wolf et al., 2017, p. 1141). Asian carp’s low selectivity by U.S. piscivores, (Wolf et al., 2017) demonstrates that using predators to control Asian carp infestations in U.S. waters will only be successful through the implementation of one of the carp’s natural predators into their new environments in the U.S.

        However as none of Asian carp’s natural predators live in U.S. water systems, all of Asian carp’s natural predators would also be invasive species to these ecosystems and their implementation into U.S waterways could cause further ecological impacts that are just as bad or worse than the negative impacts ensued by Asian carp infestations (National Wildlife Federation, n.d.). A situation similar to this occurred when the cane toad was introduced to Australia in an attempt to control pests. These toads succeeded at their job but caused many negative side-effects to the environment such as consuming large quantities of non-pest animals such as small lizards. (Frontier Gap, 2015, para. 4) These toads were able to grow in numbers and cause such havoc due to their toxic skin and glands which leave them with no predators in this new environment. (para. 4) With this knowledge at hand, the introduction of non-native predators in efforts to control the effects of Asian carp infestations does not seem like a  smart option.

        Invasive species cause vast amounts of damage to humans every year. The most recent economic study shows that the United States spends more than $120 billion every year to control invasive species (Scully, 2016, para. 3). In 2010 alone, the U.S. spent $78.5 million dollars to keep Asian carp from reaching the Great Lakes (“The cost of invasive species,” 2012, para. 11). That’s enough money to buy 20-Hubble telescopes every year (Goldman, 2012, para. 2). Even if you don’t care about fish, you should find this alarming because Asian carp affect rivers that flow in and out of the great lakes.With sixty-five million pounds of fish harvested from the great lakes every year, the lakes generate about one billion dollars in revenue for the local economy (“About our lakes: economy,” n.d., pg. 1). If Asian carp decrease native fish populations by eve one percent, that is a lot of money to lose. So clearly there is high potential for a significant problem to occur.

        So it is clear that asian carp cause problems wherever they invade. People are not blind to this and have done things to try to combat their invasion. The Army Corps of Engineers implemented an electric fence along the Chicago ship canals to keep them from moving upriver (Kraft, 2013, para 6) This is bad for two reasons. First, it stops native fish from moving along the river, and second the power for the fence has shut off, and carp moved past it (Kraft, 2013, para 6). Another option is dumping poison into the rivers to kill off the carp (Hasler, 2010, para 10). This is bad because it could kill off all of the native species along with it, and dumping poison into a river will only carry it further upstream, affecting more than just the target area. Furthermore, sometimes the poison just does not work (Hasler, 2010, para 5).  With people struggling to come up with a viable solution, we have a proposition; add a predator into to U.S. waterways to combat the Asian carp.

        Luckily there is one species of predatory fish native to the Southeastern U.S., called an alligator gar, that many scientists are arguing could be used as an effective predator of Asian carp. (“How to combat Asian carp? Get an alligator gar,” 2016). The use of a native predator could prevent against any negative effects that could be incurred from the of introduction of another invasive species to U.S. waterways. Alligator gar once existed through the Mississippi River and its tributaries all the way from Ohio to Illinois and down to the Gulf of Mexico. They now however, only live in in the Mississippi River valley from Arkansas southward (U.S. Fish and Wildlife Services, n.d., para. 12). The reason for this mass decline in alligator gar populations is mainly caused by humans. For one many people saw  alligator gars as a “trash fish” with less value than commercial game-fish and targeted them for extermination and control (para. 13). Some of the other main reasons that humans targeted alligator gar in this way include that they are big, monster looking fish, thought to attack humans and they were thought to deplete populations of commercial gamefish (Cermele, 2016). Although these two notions about alligator gars fueled the drive to eradicate these species, both of them ended up being false. There has never been a confirmed attack of an alligator gar on a human to date (Cermele, 2016, para. 6; Parks, 2016, para. 1). Additionally, alligator gar do not eat many game-fish as they are opportunistic feeders, eating anything that swims in reach of them, and most game fish are relatively stationary, meaning that if alligator gar wanted to eat them, they’d have to hunt them down, something that is just not in their nature (Cermele, 2016, para. 10; Department of Natural Resources, para. 10). Scientists have only disproven these false notion recently through studies allowing light to shine onto alligator gars potential for controlling Asian carp infestations and reintroduction efforts are already underway in Illinois (Department of Natural Resources, n.d., para. 5). State officials must consider two constraints to determine if reintroduction efforts of alligator gar in U.S. waterways will be an effective measure of combatting Asian carp infestations; effects of alligator gar on Asian carp populations and feasibility of an alligator gar reintroduction program.

        Obviously before considering feasibility of an alligator gar reintroduction, policy makers should determine the effects an alligator gar reintroduction will have on Asian carp populations in U.S. waterways. Many people including Dan Stephenson, biologist and chief of fisheries at the Illinois Department of Natural Resources, criticize that alligator gar can actually consume Asian carp, saying they aren’t big enough to do so. He says that their jaws just won’t open wide enough to fit most Asian carp (Garcia, 2016, para. 6). However alligator gar one of the  largest freshwater fish in North America and the largest fish species in the Mississippi River Valley (U.S. Fish and Wildlife Service, 2015, para. 3), an ecosystem that the Asian carp have spread throughout. At maturity they can grow to be 10 feet in length and weigh up to 300 pounds (“Alligator gar,” 2009, para. 2). On the other hand, the four Asian carp species that have invaded U.S. waterways can only grow to be at maximum, about 3.3-6 feet in length and weigh 70-99 pounds in weight (“Asian carp,” 2017). Considering that the biggest alligator gar can grow to be 3 times the weight of the biggest Asian carps in U.S. waterway and are opportunistic predators (Department of Natural Resources, n.d.), it is perfectly reasonable to assume that alligator gar can consume Asian carp, if not as full grown fish but at the very least as adolescents; which could be even more effective as it would reduce the amount of Asian carp surviving to reproductive maturity.

        Alligator gar do in fact mostly target rough fish, including carp, and gizzard shad (Cermele, 2016, para. 10, Department of Natural Resources, para. 10). Although data is scarce on alligator gar selectivity towards Asian carp specifically and is not well documented, more is known about other species of gars’ selectivity for Asian carp. According to recent research from from Western Illinois University the shortnose gar has a positive selection for Asian carp as they existed in the highest abundance, above any other prey item, in shortnose gars stomachs (David et al., 2016,  para. 5). Additionally, as previously stated, Wolf et al. (2017) found that longnose gar showed a positive selection for asian carp. Since these species are very closely related to alligator gar, it is likely alligator gar would have a similar, positive selection for Asian carp as longnose and shortnose gar and consume Asian carp in similar numbers. Alligator gar would likely even consume more Asian carp biomass per fish than longnose and shortnose gar, as they are the largest of the seven known gar species (Alligator gar et al., 2009, para. 2), adding to their effectiveness.

        With alligator gars effectiveness of controlling Asian carp infestations demonstrated, the next thing to consider is the feasibility of an alligator gar reintroduction program in U.S. waterways. Reintroduction programs have been implemented successfully in the United States on many occasions bringing animals such as California condors and black-footed ferret populations back from the brink of extinction (Errick et al., 2015). In 1982, less than 22 California condors remained. However, through reintroduction efforts by the U.S. Fish and Wildlife Service started in 1985, by 2015 there were about 210 of them in the wild and 180 in captivity (Errick et al., 2015, para. 8).

         On top of returning decimated species back to stable populations, predator reintroduction programs are also a tried and proven technique for combatting the effects of rampant species population growth. The reintroduction of gray wolves to Yellowstone National Park in 1995 had immense success combatting the effects of unwanted elk population growth. All the gray wolves of Yellowstone had been hunted to extinction by the end of the 1920s (“1995 Reintroduction of wolves in Yellowstone,” 2017, para. 4). Thereby allowing elk populations to skyrocket and mass degradation of brush and trees that elk graze on (Wolf reintroduction changes ecosystem, 2011, para. 8, 1995 Reintroduction of wolves in Yellowstone, 2017, para. 5). However, in the winter of 1995/1996, scientists captured 14 gray wolves from Canada and released them into Yellowstone Park (“Wolf reintroduction to Yellowstone Park, wolf pack dynamics, & wolf identification,” 2000, para. 2). By 2015, there were about 528 total wolves in the Greater Yellowstone ecosystem (“Wolves,” n.d., para. 6). Soon after their reintroduction into Yellowstone the environment started to return to a healthy state. This increase in ecosystem health isn’t just because the wolves ate the elk and drove their populations down. In fact elk populations have actually increased since Gray wolf reintroductions into Yellowstone. For instance in 1968, only about one-third of today’s  elk numbers existed in Yellowstone (“Wolf reintroduction changes ecosystem,” 2011, para 9). Willow tree health in Yellowstone also increased (“1995 Reintroduction of wolves in Yellowstone,” 2017; “Wolf reintroduction changes ecosystem,” 2011). If 108 gray wolves living in Yellowstone can have these positive effects on the ecosystem by consuming an increasing population of elk, it is likely that a small population of alligator gar, another top predator (U.S. Fish and Wildlife Service, 2015), can have significant positive effects on U.S. waterways by consuming Asian carp. With experience gained by the U.S. Fish and Wildlife Service from past successful reintroductions of animals such as gray wolves and California condors, the department is definitely capable of succeeding at yet one more species reintroduction, this time with alligator gar, and these efforts are already underway in Illinois (Department of Natural Resources, n.d., para. 5).

         Asian carp continue to spread and cause problems for the native fish wherever they invade. In these areas, native fish populations decrease by about half through being outcompeted themselves or through their food sources dying off (Phelps et al., 2017, p.6). With Asian carp threatening to establish themselves in the great lakes, a billion dollar per year fishing industry comes under fire, as well as an amazing and unique ecosystem. Nature controls populations through a system of checks and balances. This means that if something were to keep carp populations in check, they wouldn’t be such a big problem. For example reintroducing wolves to the Yellowstone national park region to control the effects of the elk population that was getting way out of control worked out very well and allowed the degraded conditions of the willow trees that the elk feed on to increase immensely (“1995 Reintroduction of wolves in Yellowstone,” 2017, “Wolf reintroduction changes ecosystem,” 2011). In a similar way alligator gars are the answer to keeping the effects of the Asian carp in check. They grow large enough to eat them and other gars have shown a taste for asian carp. They also were native to the region before, so reintroducing them is not some radical, new idea. If you have a large prey item, introduce a larger predator to keep it in check, and that is exactly what we propose to do with the alligator gar in regards to the Asian carp epidemic that threatens the Mississippi River Valley Basin and great lakes.

AUTHORS

Samuel Romania – Environmental Science Major

Jonathan Hastings – NRC:Fisheries

Skyler Rehbein – NRC Fisheries

 

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