Laserfiche WebLink
January 26,2024 <br /> Don Peterson <br /> Page 4 of 21 <br /> Reference: Water Quality Assessment of Silver View Pond,Mounds View,MN <br /> Table 1 Operational grouping and recycling potential of phosphorus fraction. <br /> Operational P Fraction i Recycling Potential <br /> Grouping <br /> Iron-bound P <br /> Mobile P pool Loosely-bound P Biologically-labile and subject to mobilization through <br /> biogeochemical and geochemical reactions. <br /> Labile organic P <br /> Non-mobile P pool Aluminum-bound P <br /> Calcium bound P Biologically-refractory and subject to burial; not readily <br /> available for biological uptake. <br /> Refractory P <br /> Sediment grab samples were also collected in the western forebay for sediment analysis for disposal option <br /> considerations in the event that sediment dredging would be necessary. <br /> RESULTS AND DISCUSSION <br /> The following sections provide discussion of our findings from analysis of the water chemistry, aquatic <br /> vegetation, and sediment chemistry data components of the water quality assessment in Silver View Pond. <br /> Water quality <br /> Table 2 shows the concentration range of water quality parameters collected this summer from Silver View <br /> Pond. Minnesota does not have water quality standards for stormwater ponds, so we compared the Silver <br /> View Pond data to the eutrophication standards for shallow lakes in the same ecoregion (North Central <br /> Hardwood Forest)to gauge water quality under existing conditions. <br /> Chlorophyll-a is a proxy for algal biomass and is an indicator of how productive the system is in response to <br /> elevated nutrient concentrations. Both chlorophyll-a and TP exceed the limit for shallow lakes, indicating <br /> very high productivity in Silver View Pond. Total nitrogen (TN) and total Kjeldahl nitrogen (TKN) are also <br /> elevated. Nitrite/nitrate concentrations were below the reporting limit. TKN represents ammonia and organic <br /> nitrogen, so these nitrogen data indicate that a large portion of the nitrogen pool is in an organic form. <br /> Nutrient delivery to Silver View Pond will need to be reduced in order to improve water quality and reduce <br /> frequency and duration of algal blooms. <br /> Design with community in mind <br />