KALAMAZOO RIVER / LAKE ALLEGAN WATERSHED PHOSPHORUS TOTAL MAXIMUM DAILY LOAD – AN INNOVATIVE APPROACH TO THE TMDL PROCESS

The Kalamazoo River, located in the southwestern portion of Michigan, drains into Lake Michigan. Historically, fishing and various forms of recreation, including steamship rides, were common within the watershed. With increased industrial activity, the water quality within the watershed has suffered. The Kalamazoo River is a Superfund site because of polychlorinated biphenyl (PCB) contamination from papermaking activities. Also, excessive phosphorus nutrient loadings are affecting the water quality of a 1587-acre impoundment of the Kalamazoo River, known as Lake Allegan. Lake Allegan is located in the lower reaches of the Kalamazoo River and is the recipient of both upstream urban and agricultural discharges.Sampling by the Michigan Department of Environmental Quality (MDEQ) revealed that the lake was succumbing to cultural eutrophication. Water quality data was poor, carp and catfish populations were high, and the lake had periodic algal blooms. To combat the nutrient enrichment problem of Lake Allegan, the MDEQ initiated the development of a phosphorus-based Total Maximum Daily Load (TMDL) for the watershed.The MDEQ issued a Public Meeting Notice in 1998, solicited volunteers, and formed a group that began meeting regularly to develop the TMDL. The group looked at the land covers within the Kalamazoo River Watershed and looked at the phosphorus loadings to Lake Allegan (Figure 1). It calculated the nonpoint source pollution contribution of phosphorus to be 67 percent. The TMDL Planning Committee (Committee) set water quality goals at levels similar to those of another impoundment, Morrow Lake, further upstream. Though the data from Morrow Lake was not considered ideal, conditions in the lake did not exhibit the same level of cultural eutrophication as Lake Allegan.Point Source Dischargers, representatives from National Pollutant Discharge Elimination System (NPDES)-permitted facilities, on the TMDL Planning Committee proposed an innovative approach to meet water quality goals for Lake Allegan: a cooperative agreement. They argued that cutting phosphorus permit limits even by half would not provide significant water quality benefits. They stressed that nonpoint sources of phosphorus collectively were the most significant loads to the watershed. In addition, they felt the need to allow for future growth and increased capacities at municipal wastewater treatment facilities. The MDEQ agreed with the proposed approach. The agreement was presented to United States Environmental Protection Agency (USEPA) and the TMDL was approved in May 2001. It states that Point Source Dischargers (the Waste Load Allocation) will collectively prevent any increase in phosphorus loads from April through June, and will reduce their phosphorus loadings by 23 percent for July through September. The nonpoint source discharge goal (the Load Allocation) is to reduce loadings by 43 percent from April to June and by 50 percent for July through September.The TMDL Planning Committee also developed a plan to reduce the nonpoint source pollution inputs to the Kalamazoo River Watershed. The committee established the following subcommittees to address these trouble areas: Turf Grass and Alternative Landscaping, On-site Sewage Disposal Systems, Agricultural Activities, In-stream Processes, Storm Water, Construction Activities, Transportation Activities, Lake Allegan Riparian Areas, Commercial Greenhouse Activities, Sub-basin Watershed Management, Education and Outreach, and Land Use Planning.The Cooperative Agreement has now been in effect for three years of a five-year permit cycle, and its continuation for another permit cycle will depend on the success of the phosphorus reduction strategies. The agreement fosters partnerships among all of the groups responsible for reducing phosphorus inputs within the watershed and makes it truly a watershed-wide effort to improve the water quality of the Kalamazoo River Watershed, including Lake Allegan.