TR-523 Characterization of Middle Yegua, Davidson and Deer Creeks Watersheds

Authors: Stephanie deVilleneuve, Luna Yang, Jacqueline Rambo, Michael Schramm, Allen Berthold

Middle Yegua Creek, Davidson Creek and Deer Creek have all been identified as impaired for elevated concentrations of Escherichia coli (E. coli) in the 2018 Texas Integrated Report of Surface Water Quality for the Clean Water Act Sections 305(b) and 303(d). Davidson Creek was also listed in the 2018 Texas Integrated Report as impaired for depressed dissolved oxygen. Elevated levels of E. coli have been identified in the Middle Yegua Creek watershed since as early as 2010. For the Davidson Creek watershed, elevated bacteria levels were first identified in 2002 and depressed dissolved oxygen in 2010. For the Deer Creek watershed, the bacteria impairment was first identified in 2006. This characterization addresses the E. coli impairments in the Middle Yegua Creek, Davidson Creek and Deer Creek watersheds with supplementary water quality monitoring and a review of the current demographic, climatic, physical and hydrological conditions of the watersheds. Existing data for water quality parameters, flow, livestock, wildlife, stormwater permits and a number of on-site sewage facilities have been analyzed to develop a better understanding of potential causes and sources of bacteria pollution.