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Explore contemporary issues in groundwater management in U.S. urban areas, including flooding, karst geology risks, water rights disputes, fluoride contamination, nitrate pollution, pesticide concerns, and fracking impacts.
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Contemporary U.S. issues in groundwater CE 473/573 Fall 2011
Flooding in Fargo, N. Dakota Flooding in Fargo, ND causes millions of dollars of damage every year. Solutions to this problem, which include diverting the water and building protective structures, will cost over a billion dollars. Finding the funds is challenging since the federal, state, and city governments already have tight budgets, and they do not want to channel all of the cost to the taxpayers. At the same time, Fargo cannot afford to keep putting the time and effort into flood prevention every spring. In this class, we would like to learn more about cost effective ways to deal with flooding in urban areas. Image source
Karst hydrology in Kentucky Increased urbanization is causing harm to the karst regions of Kentucky region. Karst geography can be unstable because groundwater can erode caves and shafts in the ground. These pockets can collapse and cause sinkholes, which can be very detrimental to any type of structure. Increasing urbanization in the areas must be approached with caution since the increased runoff from urbanization speeds up the natural process significantly. To help combat the problem a large effort is underway to use GIS mapping and other technology to better understand where and how much urbanization can be withstood before sinkholes and other damage will occur. In CE 473 we would like to learn a little about how this process works and perhaps how some of the calculations are carried out. Image source
Water rights in Montana & Wyoming In a 2007 lawsuit Montana complained that Wyoming is violating the Yellowstone River Compact by removing too much water from the rivers and water rights holders in Montana are not receiving enough water. Montana also alleged that withdrawing groundwater is reducing river flows, thereby further reducing available water. Image source The current Court decision supported upstream (Wyoming) users and declared that there is no obligation for upstream users to consider downstream water user needs. The pending decision regarding groundwater supplies between the two states could affect the energy industry. The Yellowstone River Compact was established to address water rights issues, but it does not explicitly address groundwater. How should groundwater flow be quantified as part of the system, how does groundwater affect the river and should groundwater and surface water be treated as one system under water rights laws are questions we could evaluate in this class.
Fluoride in E. South Dakota Groundwater in eastern South Dakota contains large fluoride concentrations. These large concentrations can cause mottling of tooth enamel in children and fluoride poisoning, which can lead to nausea, vomiting, diarrhea and death. The World Health Organization has recommended that fluoride levels in water sources should not exceed 1.0 mg/L. Reducing the level of fluoride in groundwater can be achieved by adding a defluoridation step to the water treatment plant, which will increase the cost of the plant and drinking water. Testing fluoride levels is important, especially in rural areas where every household has its own well. However, testing a private well can be expensive. Image source
Increasing nitrate in the Mississippi R. Between 1980 and 2008 the concentration of nitrates in the Mississippi River have increased, and farm fields and sewage plants are to blame. Efforts to control nitrate levels by filtration on farms and more advanced treatment plants may not work for a long time due to slow flow of the nitrates in soil, as discussed in class. Lab measurements of seepage velocity will increase understanding of when the results of the preventative measures will start to improve. It will be interesting to learn how pollutants like nitrate travel through groundwater and make their way into streams as well as other preventative measures that could have been used in this situation after the nitrates infiltrated the groundwater. Image source
Pesticides in Idaho’s groundwater Idaho is worried about pesticides contaminating the groundwater in the state. Studies and tests have shown that pesticides are in the groundwater, but not at levels above EPA standards. Pesticides are often used in farming applications and then occasionally get into the groundwater and contaminate the water used by humans and other living species. These are harmful and a solution is needed to prevent the contamination. Since Iowa is heavily farmed and uses similar chemicals during the farming process, we want to know what kinds of solutions are possible to limit and treat the contamination.
Hydro-fracking in Pennsylvania Fracking helps extract natural gas, but the wastewater contains corrosive, carcinogenic, and radioactive materials that threaten the water supply and recreation for more than 80,000 people. Residents have complained about the location of these operations in Pennsylvania and other states. Image source