A watershed assessment study is being conducted for Big Cotton Indian Creek and Walnut Creek watershed as part of the county's plan to upgrade wastewater treatment plant capacity. ARCADIS developed a work plan for Georgia Environmental Protection Division (EPD) to obtain their approval prior to initiating the study. The work plan includes a preliminary biological assessment water quality monitoring plan and comprehensive watershed management plan. ARCADIS selected 18 monitoring locations for extensive wet and dry weather sampling and biological assessments.

Henry County is a rapidly developing county, and the assessment poses a significant challenge as to the impacts on the comprehensive land use plan. BASINS computer model is being utilized to simulate both existing and future land use conditions. The model will be used to perform "what if" scenarios to develop a watershed protection plan that will minimize impacts on land use yet maintain EPD's water quality standards.

The study will result in a watershed management plan that will address the sources of water impairment and ways to improve water quality throughout the watershed. The plan will be used to implement water management practices to control and improve non-point sources of pollutions from urban areas and agriculture lands. Point sources of pollutants from stormwater and permitted municipal and industrial discharges will be assessed to see how improvements could reduce pollutant loads. The plan will include an implementation plan to install improvements, as well monitoring the effects of the improvements.