R2026-134 - Resolution Authorizing a Memorandum of Understanding for Development of a Regional Integrated Plan for Wastewater and Stormwater for Decatur, Illinois

Home Browse Search

Memorandum of Understanding for Development of a Regional Integrated Plan for Wastewater and Stormwater for Decatur, Illinois June 1,2026 Parties and Purpose This Memorandum of Understanding (MOU) is entered into by and between the Sanitary District of Decatur(SDD), the City of Decatur. The purpose of this MOU is to outline the collaborative efforts and responsibilities of the Parties to develop a Regional Integrated Plan for Wastewater and Stormwater for Decatur. The need for an Integrated Plan is largely driven by SDD's Nutrient Assessment Reduction Plan (NARP)which is intended to achieve targeted reductions in phosphorus loads to address phosphorus-related impairments in the Sangamon River. The Parties also have additional water-related obligations and goals. This agreement aims to foster cooperation and help ensure that all Parties work together effectively to meet the environmental goals set by themselves and those goals forth by the Illinois Environmental Protection Agency (Illinois EPA). Background The integrated plan will be developed for the Upper Sangamon River from river mile 87.3 to river mile 132.6, as shown in Attachment 1. This area includes the Lake Decatur dam and the NARP study area reach for SDD, including the watersheds draining directly to this reach. SDD provides wastewater treatment for residents and businesses in the City of Decatur and Villages of Argenta, Forsyth, Mt. Zion and Oreana. Portions of the wastewater collection system in the City are combined sewers (which convey both sanitary sewage and stormwater runoff); SDD is responsible for treatment at four combined sewer outfalls. SDD is also responsible for interceptor sewers and the operation and maintenance of 20 SDD-owned lift stations and 21 City-owned sewage lift stations. The City of Decatur is responsible for the collection systems including combined sewers, separate sanitary sewers and the municipal separate storm sewer system (MS4) within its boundaries. The City owns and operates drinking water treatment facilities, including Lake Decatur and supplies drinking water to the residents of Decatur and some surrounding communities. The Illinois EPA established NARP Special Conditions in National Pollutant Discharge Elimination System (NPDES)permits for certain major publicly owned treatment works (POTWs) in Illinois. These conditions require facility improvements to achieve targeted reductions at WRRFs and identify actions required to eliminate phosphorus-related impairments in the receiving waters. Phosphorus removal at the SDD WRRF is unique due to the high average influent total phosphorus (TP) concentration at 22 milligrams per liter(mg/L). To complete the NARP, SDD hired consultants to evaluate nutrient loading to the Sangamon River.