Platte River State Fish Hatchery Settlement Agreement Compliance History: 2000 to 2008

Platte River State Fish Hatchery has served as the primary Pacific salmon hatchery for the State of Michigan since the inception of Michigan DNR’s salmon management program.  In the early years of the program, rearing numbers rose steadily and insufficient attention was paid to effluent management.  This resulted in degradation of water quality in Big Platte Lake.  In 1986, the Platte Lake Improvement Association (PLIA) filed suit against the hatchery for its effect on water quality.  In March of 2000, a settlement agreement between the PLIA and MDNR was reached.  The terms of the agreement included a calendar year net total phosphorus discharge limit of 175 pounds and a rolling three month limit of only 55 pounds, as well as a requirement that the hatchery provide all manpower and virtually all funding to conduct an extensive water sampling program aimed at understanding the phosphorus dynamics of the Platte River watershed and Big Platte Lake, in particular.  In order to meet the discharge limits, a large scale renovation of the outdoor rearing system and installation of a more aggressive effluent management system was completed in 2004.  Since the beginning of the sampling program, over 40,000 phosphorus samples from the Platte River watershed have been developed.  A comprehensive mass balance model of the system has been developed and various aspects of sampling methodology have been exhaustively evaluated.  An Access database, with extensive reporting capabilities, holds all of the data from this watershed study.