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® , existing water quality parameters within wetland <br />Where possible, the above -listed data will be collected <br />from the City, the watershed district, the engineers who <br />designed the wetland, and from the Minnesota DNR. Water <br />quality parameters will be obtained by submitting samples to <br />a certified laboratory. <br />Task 2. Water Quality Analysis <br />Ambient water quality data will be studied to estimate <br />the present nutrient pollution level in wetland 893 and to <br />determine its existing trophic level. In addition to data <br />available from tte Minnesota DNR and PCA, water samples will <br />be taken from the wetland during critical times of the year. <br />These time periods will include the early spring when the <br />first nutrient surges enter the wetland, aid -summer and the <br />late summer when hot weather and low water magnify the <br />effects of nutrient pollution. A total of three (3) samples <br />will be taken for total phosphorus, total nitrogen, <br />chlorophyll and algal identification. On each of the three <br />® dates, the lake will be sampled at three locations. <br />Anticipated future changes in water quality will be <br />estimated by reviewing the City's compre:,ensive land use <br />plan and the development potential of the portion of the <br />wetland's watershed which remains undeveloped. Using <br />standard nutrient loading models, projected nutrient loads <br />from future development will be added to present loads to <br />estimate future conditions. Again, a d^terminatior will be <br />wade whether the anticipated nutrient level will exceed any <br />thresholds at which perceptible changes in trophic level <br />would occur. <br />A num'er of water quality control measures will be <br />investigated, either to maintain or improve upon existing <br />conditions. These measures potentially include: <br />1. Limiting the amount of new stormwater to be directed to <br />the wetland in the future. <br />2. Provision of pre-treatment of stormwater inflows through <br />use of detention ponds. <br />3. Limiting the future generation of nutrients within the <br />wetland's watershed through improved street sweeping <br />techniques, reduced lawn fertilization, and/or requiring on - <br />site stormwater treatment for new developments draining <br />toward the wetland. <br />