VLAWMO Annual Financial Report 2007

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Below are typical measurements one might find for lakes and streams in the CHF ecoregion: Lakes Field pH TSS (mg/L) NOx (µg/L) TP (µg/L) Turb (NTU) SDT (m) ( Chl-a (µg/L) TKN (µg /L) 8.6-8.8 2-6 <100 23-50 1-2 1.5-3.2 5-22 600-1200 Streams Field pH TSS (mg/L) NOx (µg/L) TP (µg/L) Turb (NTU) Fecal Coliform (cfu/100 ml) Temp (°C) BOD (in mg/L) 7.9-8.3 4.8-16 4-26 6-15 3-8.5 40-360 2-21 1.5 —3.2 Water Quality Standards for VLAWMO The MPCA has water quality standards based on a designated use for the water body. VLAWMO's water is classified as "2B". The SPRWS chain of lakes has a stricter designation of "2Bd" due to it being the drinking water source for St. Paul. The quality of Class 2B water must be suitable for aquatic recreation of all kinds as well as to support fish and aquatic plant life. In 2008, the MPCA will approve new standards which will separate deep from shallow lakes. All of the lakes VLAWMO monitors are considered shallow and therefore those standards will apply. For those parameters which the MPCA does not have standards, the federal Environmental Protection Agency (EPA) has maximum contaminant level standards. VLAWMO's goal is to have its waterbodies within these standards. MPCA Standards Lakes EPA Standards TP (µg/L) Chl A (µg/L) SDT (m) Turb (NTU) TSS (mg/L) TKN (µg/L) NO2 (µg/L) < 60 < 20 > 1 < 25 < 100 < 1000 < 100 MPCA Standards — Rivers and Streams EPA Standards Fecal Coliform daily maximum (cfu/100 ml) Fecal Coliform 30 day mean (cfu/100 ml) Turb (NTU) TSS (mg/L) NH3 (µg/L) TKN (µg/L) NO2 (p.g/L) < 1260 < 126 < 25 < 100 <40 < 1000 < 100 Precipitation in 2007 Major factors influence water quality including the amount of precipitation, timing of precipitation events, and land use practices in the watershed. Long-term monitoring is necessary to characterize the impacts of various land use practices on surface water runoff within VLAWMO. The 2007 monitoring season began with a drought that lasted until mid August when there were nine significant storm events (> 0.5") over a period of six weeks. Despite the heavy rain events in late summer, the season was still nearly 5" short of average. Precipitation moves contaminants resting on lawns, roofs, streets, and parking lots into nearby water bodies or into storm sewers that outlet into water bodies. Typically, the more precipitation that occurs, the more runoff there will be in the watershed. However, the timing and intensity of the precipitation, as well as soil types, land slopes, land uses, as well as other factors can influence the amount of runoff that reaches the water bodies.