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1 � � <br /> Conclusions <br /> Prior existence of the swale is difficult to detect from the aerial photos due to the presence of tree cover and the small size <br /> of the swale.The appearance of the swale and the fact that the adjoining soils are non-hydric indicates that the swale <br /> was created to concentrate the surface flow of water across the eastern part of the parcel and direct it across the driveway <br /> to the west. The site plan shows a pocket at the end of the swale where the water collects and is delivered through the <br /> culvert beneath the driveway to the catchbasin in the lawn. Given the lack of topographic gradient, any attempt to provide <br /> for gravity flow of water to the lake resulted in the construction of drainage features that were below, at,or just barely <br /> above the OHW. <br /> Any wetland conditions existing on the properly are the result of attempting to remove surface water effectively but the <br /> result was the backflow of water from the lake into the drainage structures resulting in conditions of persistent wetness <br /> during those times that the lake is at or above the OHW. <br /> We would recommend that the proposed low area east of the driveway (see site plan drawing)be vegetated with a BWSR <br /> recommended wet prairie seed mix with a colorful wildflower component to provide visual enhancement. The low area <br /> would provide for periods of surface water storage,water infiltration and water quality enhancement. Following these <br /> recommendations would pre-treat water entering Lake Minnetonka when lake levels are below 929.2' and would provide <br /> for brief periods of inundation and saturation when water levels are above that elevation. <br /> Since the area around the catch basin is persistently wet during those periods when lake water levels are above 928.46', <br /> creating a more formal and enhanced"wet"area would be more beneficial than trying to maintain a lawn around a culvert <br /> outfall that is wet or saturated much of the time early in the year. Taking advantage of this water influx and creating a wet <br /> meadow plant community would be more amactive than attempting to maintain a lawn.At the same time,the catchbasin <br /> outfall would be camouflaged. <br /> Please feel free to contact Frank Svoboda at(952) 471-1100 if you have any questions regarding the information in this <br /> report. SER appreciates the opportunity to assist you with this project and we look forward to serving any future needs <br /> that you might have. <br /> Sincerely, <br /> Svoboda Ecological Resources <br /> �`�---- d. . .���-.— <br /> ��� <br /> Franklin J. Svoboda, CWB,PWS Brian K.Burgner, WDC <br /> President Wetland Ecologist II <br /> Cc: Bruce Schmitt-Bruce Schmitt&Associates <br /> Attachments : Figures—Aerial Photo with Soil Sample Locations Overlaid <br /> Hennepin County Soil Survey <br /> Interpreted Soil Boundaries Based on Site Evaluation <br /> Drawing— Site Plan by Gronberg&Associates <br /> Datasheets—Select Soil Borings <br />