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Page: 4 <br /> <br /> <br /> <br />areas must be protected by easements shown on the preliminary and final plats, site plans, and <br />grading plans. <br />7. If wetlands are permitted on private lots, each lot must have a minimum of 1.25 acres of land <br />above the wetland HWL elevation and free of any drainage easements. <br />8. Stormwater Basins must be designed and constructed in accordance with the City engineering <br />design standards. <br /> A 10:1 maintenance bench is required around the BMP perimeter. <br /> A 10:1 aquatic bench is required around the BMP perimeter. <br /> The minimum permanent pool depth is 4‐feet. <br /> Pond 4 and Pond 5 must be revised to eliminate wetland and wetland buffer encroachments. <br />9. Maintenance access roads must be a minimum of 20‐feet in width from the public right‐of‐way to <br />the basin with grades not exceeding 10%. Maintenance access remains inadequate or incomplete <br />for Ponds 1, 2, 3, and 5, and for Filtration Basins 1E and 2W. <br />10. The grading plans remain unclear whether overland stormwater conveyance can be adequately <br />designed and constructed to ensure the minimum hydrology requirements are maintained for <br />each proposed BMP. <br /> Should the City agree to allow the construction of rural section streets and long overland ditch <br />conveyance systems to the BMPs, it is strongly recommended that staff be directed to <br />research and prepare alternative engineering design standards for overland drainage <br />conveyance if storm sewer piping is not utilized. <br /> <br />MUNICIPAL WATER SUPPLY <br />1. Connection to the municipal water system is available near the proposed development in two <br />locations. The applicant will be responsible for connecting to the existing 16‐inch trunk watermain <br />located along Inwood Avenue (CSAH 13). An 8‐inch ductile iron watermain will need to be <br />extended along the new streets into and throughout the development at developer’s sole cost, <br />and to serve each proposed parcel in the Subdivision. <br />2. A second connection point is required to create a looped watermain system, connecting to the <br />existing 8‐inch watermain located along Imperial Avenue in the adjacent Lake Elmo Heights <br />neighborhood. This secondary connection will require the installation of a pressure reduction <br />valve (PRV) as the Lake Elmo Heights neighborhood is located in the intermediate pressure zone <br />while the proposed subdivision is located in the high‐pressure zone. <br />3. The Sketch Plan shows the required watermain improvements, however the plans do not show <br />the required Pressure Reducing Valve (PRV) and vault. The PRV will need to be located so that the <br />valve and vault reside outside of the street pavement surface. An off‐site drainage and utility <br />easement may be necessary for the PRV installation. <br />4. No watermain oversizing reimbursement is applicable for this development. <br />5. The developer will be responsible to place hydrants and water system valves internal to the site <br />as determined by the Lake Elmo Public Works Director and Fire Department. Hydrant and system <br />valve locations will be reviewed and finalized as part of the final construction plans. If a rural <br />section street is allowed to be installed, staff must be directed to research and prepare alternative <br />engineering design standards for the placement of hydrants along the rural roadway. <br />6. Minimum 30‐foot easements centered over the pipe/hydrant will be required when not located <br />within the public right‐of‐way. Easements must be free from all encroachments, including <br />retaining walls, trees, fences, small/dry utilities, or storm water management BMPs. Dedicated <br />utility easements must be shown on all site, grading, utility, and landscape plans when submitting <br />a Preliminary and Final Plat application. <br /> <br />WATEWATER MANAGEMENT / SUBSURFACE SEWAGE TREATMENT SYSTEMS (SSTS)