Trophic State of Lakes in the Blackfoot & Swan Basins.
Vicki Watson, UM Watershed Health Clinic,
Mike Suplee, Mt. Department of Environmental Quality,
Jolanta Glabek, UM Watershed Health Clinic
ABSTRACT: In 2003 & 2004, the Montana Department of Environmental Quality & the University of Montana collaborated on a survey of Montana's lakes to develop a lake classification system based on key physical, chemical & biological characteristics. Study lakes in the Clark Fork basin were concentrated in the Blackfoot & Swan River drainages and included a group of lakes intensively studied in the 1970's & early 1980's by UM researchers Richard Juday & Ed Kellor. Key indicators of lake trophic state were computed from recent & historic data and compared. Historic data showed more productive lake trophic states than the 2003-04 data. It is likely that the lakes have experienced some recovery since the heavy logging of the 1960’s and 70’s. Despite the increase in residential development around the lakes in recent years, the lakes seem to have improved since the 1970's & 80's. However, continued growth in residential development may cause the lakes to degrade in the future. The 2003-04 data provide a baseline against which development impacts can be judged in future.
Watershed Health Clinic, University of Montana, Missoula, MT 59812
MT Dept. Environmental Quality, 1520 E. 6th Ave, Helena, MT 59620