Maine Department of Environment Protection lake monitoring and assessment, 1970s-2011, compiled all ME DEP programs for metadata unpublished data

Much of the lake monitoring in the state is done to assess "trophic state" or the productivity of the water. Our 30 year record includes data on over 1000 of our 5785 lakes, including parameters such as transparency, conductivity, alkalinity, total phosphorus and chlorophyll-a. These, along with extensive data sets from the University of Maine and clarity readings from volunteers, have produced one of the most comprehensive lake data sets in the country. DEP regular monitoring includes annual Baseline Sampling Program and special projects of one or more years’ duration. Each year between August 10 and September 10, we visit over 100 lakes and take a number of types of data. The timing coincides with the period when lakes usually show their worst water quality: lowest dissolved oxygen, lowest transparency and highest algae and phosphorus levels. Besides these measures, we sample for conductivity, alkalinity and acid neutralizing capacity (ANC), true and apparent color, and a variety of cations and anions. Lakes sampled generally include TMDL lakes, 33-50 lakes in the VLMP, lakes of special concern (e.g., anecdotal report of algal bloom), long-term monitoring lakes in ecoreserves and special project lakes.