Spavinaw Creek

The first dam was built in 1923 creating Lake Spavinaw as part of the Spavinaw Water Project. Much of the town of Spavinaw had to be relocated to higher ground. The purpose of the lake was to supply water to the city of Tulsa.^[5] The creek was dammed a second time in 1952, creating Lake Eucha as an expanded storage for the Spavinaw system.^[6]

The land usage was shown in a 2002 study to be predominantly livestock and poultry with a small percentage of row crops. There were 54,172 head of cattle and calves, 128,066,609 Broilers & chickens, and the number of Hogs & pigs was not determined in Delaware County, OK. There were 40,251 head cattle and calves, 37,154,935 Broilers & chickens, and 285,661 in Benton County, AR. The result of water quality testing showed a high concentration of phosphorus resulting in algae growth. A major tributary to Lake Eucha, Beaty Creek, was found (2004 study) to be impaired by pathogens, specifically Enterococcus. There can be many causes of contamination such as faulty septic systems, wildlife and livestock grazing fecal bacteria, unstable stream banks, municipal and industrial storm water and waste water discharge, commercial fertilizer, pet waste, soil erosion, and "confined/concentrated animal feeding operations" (CAFOs) such as the many poultry farms. The Decatur, Arkansas waste water treatment plant also includes waste from a poultry processing plant. Large poultry operations are considered point sources whereas smaller operations are not but cumulatively contribute to the phosphorus loading in the watershed. The city of Tulsa brought court proceedings that resulted in a ruling for a reduction in discharge of phosphorus from the city of Decatur and poultry producers in the watershed to improve water quality as well as reduce treatment costs. Both Lake Spavinaw and Lake Eucha have been designated as “sensitive public and private water supply” (SWS) and “nutrient limited watershed” (NLW). Any increase in discharge must receive prior approval. 72 poultry producers in Oklahoma and 22 in Arkansas are cooperating in the best management practices (BMP) to reduce nutrients in the watershed.^[7][8]