Water Online

May 2017

Water Innovations gives Water and Wastewater Engineers and end-users a venue to find project solutions and source valuable product information. We aim to educate the engineering and operations community on important issues and trends.

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sources are a de minimis contributor ... it will be exceedingly difficult for ... utilities to garner community support and funding for expensive treatment technologies that result in little to no improvement in overall water quality. ... This is especially evident in the Gulf of Mexico and Chesapeake Bay." 10 The Iowa Example In Iowa, a few dozen miles upstream of Des Moines, lay the most productive corn and soybean farming in the world. Called the Des Moines Lobe, it also produces the largest nutrient loads to the Gulf of Mexico. 11 Not surprisingly, the Des Moines River's average nitrate level veers to 13 mg/L, compared to EPA's maximum limit 10 mg/L. 12 The City of Des Moines uses this river for drinking water; its utility spends up to $7,000 daily for nitrogen treatment to produce legal drinking water. Another $180 million may be needed to treat the farm-impacted water. 12 Ironically, a few miles downstream of Des Moines' river intakes, their wastewater authority spent $1 billion for upgrades to reduce emissions. So costly is Des Moines' plight that its Water Works' CEO (an attorney), Bill Stowe, is spearheading a groundbreaking lawsuit against upstream counties governing agricultural drainage districts in order to stop the districts' nutrient releases. A true leader among water authority administrators, Stowe has stoked a virtual war in corn country: Big City vs. Rural Agriculture. Yet, six months before Des Moines filed suit, a few miles from Stowe's office, another brilliant leader, Dean Lemke, worked to address the problem at the Iowa Department of Agriculture and Land Stewardship. Lemke directed a precedential assessment of edge-of-field and on-farm nutrient reduction techniques when he published the Iowa Nutrient Reduction Strategy. Apparently ignored by regulators was the report's finding that constructed wetlands can reduce nitrogen loads for $2,800 per ton, bioreactors can do so for $1,800 per ton, and controlled drainage management and buffers work at $2,500 to $3,800 per ton. 13 The report acknowledged that 130 of Iowa's wastewater plants will be permitted to reduce nitrogen for about $6,800 per ton — in order to decrease statewide loads 4 percent. Why are Iowa's ratepayers subsidizing expensive sewage technologies for a mere 4 percent reduction? Such a scheme is like an elephant giving birth to a gnat: implausible and painful to watch. Based on the state's figures, if Iowans were to subsidize farm-centric mitigation rather than end-of-pipe wastewater technology, nitrogen loading could decrease threefold. As the EPA's Iowa "regulate the wastewater plants" strategy inevitably fails, Iowans should expect their costs to go even higher as regulations spiral; engineering and construction firms win, farmers take flak, Iowa and the environment loses — just like the Chesapeake. Cost-Effective Accountability The economic elegance of mitigating nutrient sources near to the farm is bootstrapped by additional science. Engineers from powerhouse Black & Veatch calculated what it would take to cut nutrients in the Illinois River Basin with simple near-stream treatment plants. Reducing nitrate loads to the Gulf of Mexico by up to 20 percent was estimated to require merely $760 million, at less than $2,000/ton of nitrogen removed. 14 By comparison, Rockford, IL, spent an extra $30 million to remove about 3 mg/L of nitrogen, a marginal cost of around $5,000/ton. 15 In the Chesapeake, enhanced nitrogen removal at sewage plants has cost $6,000/ton. 16 The Wetlands Initiative in Illinois analyzed seven Chicago wastewater plant upgrades. They determined 200,000 acres of passive wetlands would save $1.6 billion, compared to Chicago's retrofits. 17 From the National Association of Clean Water Agencies, "The cost to remove a pound of nitrogen or phosphorus from farm runoff and drainage is typically 4-5, sometimes 10-20, times less than the cost to remove the same amount from municipal wastewater or stormwater." 18 Confounding environmentalists is the reality that as EPA wateronline.com n Water Innovations 9 REGULATIONS

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