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-----------------�-- -�---- ----__... _- -- _ <br /> — _ �.. ___.. _ _ _ .�_ --- _ . _. , - <br />= --�-----_--- -�-.. -----�-�_-_- - --�---�--'�----- - - - . _ - - -,..� - -- .±` _._ _ _ <br /> -,:.:._____�..�,� - <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 pla.n 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 property 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_atea 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 azound 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 eazly in the year. Taking=advantage of this water influx and creating a wet <br /> meadow plant community would be more attractive than attempting to maintain a lawn.At the same time,the catchbasin <br /> outfall would be camouflaged. - - ----------�----- �-- •- - � <br /> Please feel free to conta.ct 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 /> --- - - __ _ . _ _- - _- ----- - - - <br /> Drawing- Site Plan by Gronberg&Associates - ----- � -- - - - - • � <br /> Datasheets-Select Soil Borings � <br /> � <br />