Laserfiche WebLink
to provide the Applicant with substantial enjoyment of his property by providing privacy, <br />security and child safety. <br />Retaining Wall and Grading. <br />As shown in the topographical survey, the elevation of the southern half of the Applicant's <br />property is below the surface elevation of Bracketts Point Road. As a consequence, street <br />storm.water has traditionally drained onto the site. To provide storm.water rate control and water <br />quality control, the Applicant proposes to construct a retention area (i.e., an infiltration area) in <br />the southerly portion of the prope1iy. On the easterly portion of the infiltration area (i.e., <br />"upland" or towards Bracketts Point Road) a stone retaining wall will be constructed to enhance <br />the capacity of the infiltration area in a relatively flat portion of the site. A swale will be <br />constructed to direct stonnwater runoff from Bracketts Point Road and the property to the <br />infiltration area. Because the topography in this area is extremely flat and only slightly above <br />the Ordinary High Water Elevation of Lake Minnetonka, drain tile will be placed under the swale <br />and retaining wall to provide minimal gravity flow (at 0.4% slope) into the infiltration area. No <br />outlet directly into the lake is being proposed. The retaining wall will not encroach into the <br />lakeshore setback area, although the grading to create the infiltration area will encroach. The <br />infiltration area and swale will be planted with native floodplain species and it is expected that <br />the vegetation will provide some degree of water quality treatment. <br />In addition, it is necessary to elevate the area of the driveway in the floodplain so that the <br />Applicant may access his property during wet periods or when the elevation of Lake Minnetonka <br />is higher than normal. The mean high water level of Lake Mim1etonka typically rises by at least <br />7 inches during the spring and summer. The elevated area of the driveway will be held by two <br />retaining walls on either side of the driveway entrance from Bracketts Point Road. A culvert will <br />pass beneath the driveway entrance and through the retaining walls to allow storm.water to <br />continue to flow through the swale into the infiltration area. <br />As shown by the attached Site Grading and Drainage Plan, the volume of fill in the floodplain <br />will be compensated by the volume of the cut into the floodplain. The holding capacity of the <br />floodplain, thus, should not be diminished, as demonstrated in the enclosed floodplain volume <br />calculations. <br />The topography at the southerly end of the site together with the configuration of Bracketts Point <br />Road as it travels south necessitates that stonnwater handling be addressed in this single family <br />residential development. The proposed variance will not impair public health or safety; but <br />rather is expected to advance environmental concerns by handling storm.water runoff from <br />Bracketts Point Road in an environmentally responsible manner. Finally, by constructing the <br />infiltration area together with the retaining walls and elevation of the driveway entrance, the <br />Applicant's access to and enjoyment of his property will be enabled by treating and handling <br />storm.water from the adjacent street in a controlled and environmentally responsible way. <br />#2956541 \2