Loading...
ITEM 3.1    ENGINEERING REVIEW Residential Subdivision for the City of Otsego by Hakanson Anderson Review No. 1   Submitted to: Honorable Mayor and City Council cc: Adam Flaherty, City Administrator/Finance Director Tami Loff, City Clerk Dan Licht, City Planner Andy MacArthur, City Attorney Mike Suel, D.R. Horton, Inc. John Bender, Westwood Professional Services, Inc. Reviewed by: Ronald J. Wagner, P.E. Brent M. Larson, P.E. Date: July 10, 2018 Proposed Development: Magnolia Landing Street Location A portion of the S ½ of the SW ¼ Section 31, T121, Range 23 Of Property: all East of Marlowe Avenue NE and South of 63rd Street NE. Applicant: Mike Suel Developer: D.R. Horton, Inc. 20860 Kenbridge Court, Suite 100 Lakeville, MN 55044 Owners of Record: D.R. Horton, Inc. Purpose: Magnolia Landing is a proposed 67 single-family low density residential lot development on approximately 42+ acres in the City of Otsego, Wright County, Minnesota. The proposed development will be served with municipal water, sanitary sewer, storm sewer, and public streets typical of an urban setting. Jurisdictional Agencies: City of Otsego, Wright County, Minnesota Department of (but not limited to) Health, Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, Wright Soil and Water Conservation District. Permits Required: NPDES, Minnesota Department of Health (water), (but not limited to) Minnesota Pollution Control Agency (sanitary sewer), and Wright County PAGE 2 S:\Municipal\Aotsego23xx\2339\ot2339 RVW1.docx   TABLE OF CONTENTS INFORMATION AVAILABLE EXISTING CONDITIONS SUBDIVISION CONFIGURATION, LOT SIZE, DENSITY PRELIMINARY PLAT/STREET/TRAFFIC PRELIMINARY GRADING, DRAINAGE, AND EROSION CONTROL PLAN PRELIMINARY UTILITY PLAY SURFACE WATER MANAGEMENT WETLANDS ENVIRONMENTAL SUMMARY AND/OR RECOMMENDATION PAGE 3 S:\Municipal\Aotsego23xx\2339\ot2339 RVW1.docx   INFORMATION AVAILABLE Preliminary Plans for Magnolia Landing, dated 6/19/18, by Westwood Professional Services, Inc. Geotechnical Soil Borings for Magnolia Landing, dated 6/18/18, by Braun Intertec Corporation Stormwater Management for Magnolia Landing, dated 6/19/18, by Westwood Professional Services, Inc. Storm Sewer Design for Magnolia Landing, dated 6/19/18, by Westwood Professional Services, Inc. Additional Information Minnesota Rules, Chapter 4410 – EAW Requirement City of Otsego Engineering Manual City of Otsego Zoning and Subdivision Ordinances National Wetland Inventory Map PAGE 4 S:\Municipal\Aotsego23xx\2339\ot2339 RVW1.docx   EXISTING CONDITIONS 1. Existing zoning classifications for land abutting the subdivision shall be shown on the plan. 2. Existing names of streets outside of subdivision shall be labeled on the plan. 3. Label the size and elevations of existing storm sewer, water and sanitary or any other underground facility within 150 feet of the proposed plat. (21-6-2.B.5.) See attached as- built plans for adjacent utility information. 4. Label NWL and 100-yr HWL elevations for the existing ponds and wetlands. 5. Provide benchmarks and datum (should be NGVD 1929 adj. datum). SUBDIVISION CONFIGURATION, LOT SIZE, DENSITY 6. Wetland buffer and setbacks are labeled 10’ in note for rear yards of Lots 1-3, Block 3 and Lots 4-5, Block 4. This is less than allowed. PRELIMINARY PLAT/STREETS/TRAFFIC 7. Street shall be named according to the Wright County street naming system as follows; a. Street 1 – Marx Avenue NE b. Street 2 – Martin Avenue NE c. Street 4 – Marx Court NE 8. All Right of Way shall be rounded at intersections. 9. Provide horizontal curve and tangent information for the streets. All streets shall have 250’ min. horizontal curves and 100’ min. tangents between curves. If a 90-degree bend is allowed in the street, a 90’ horizontal curve is required. 10. Temporary cul-de-sacs are required at south ends of Marshall Avenue and Martin Avenue. PRELIMINARY GRADING, DRAINAGE, AND EROSION CONTROL PLAN 11. Concrete valley gutters are required across all intersections with less than 1% cross slope (i.e. North leg of Marshall Avenue at 62nd St and at Marx Court and Marx Avenue). 12. 1.5’ of freeboard is required form the emergency overflow to low opening/garage floors of Lots 7&10, Block 4. Currently the EOF is 947.6 and garage floors are at 948.8. 13. The finished ground elevation at the rear of Lot 4, Block 4 appears to be a typo. Please verify and revise. PAGE 5 S:\Municipal\Aotsego23xx\2339\ot2339 RVW1.docx   14. The current maintenance paths to the ponds have very tight turns. Please round these out to allow trucks to make said turns. PRELIMINARY UTILITY PLAN 15. The size and type of all proposed sewer and watermains shall be shown on the plan. 16. The gradient of all proposed sewers shall be shown on the plan. 17. A tenth foot of fall shall be required across all sanity manholes. 18. No inverts or rim elevations are labeled for the storm sewer. Final plans will be checked for cover. 19. The general utility note references the 1999 CEAM and 2005 MnDOT Spec. The City requires all streets and utilities to conform to the 2013 CEAM and 2018 MnDOT Spec. DETAILS 20. The Otsego Engineering Manual has been updated as of March 2018. Please use the updated Otsego Standard plates from this revision. SURFACE WATER MANAGEMENT 21. Provide the pond/wetland NWL elevation on the drainage area map. 22. The Stormwater Management Plan and drainage calculations appear to meet City and NPDES Standards. 23. The need for Pond 4 it is a little unclear. The drainage area appears to only be rear yards and the discharge from this pond is routed to Pond 1 so it is treated again. Please consider and review using a rear yard storm sewer with catch basins to eliminate the need for this pond. WETLANDS 24. Please submit a Wetland Determination Report for review. ENVIRONMENTAL 25. A statement certifying the environmental condition of the site including the presence of any hazardous substance as defined in Minnesota Statutes 115B.02, Subd 8 is required. SUMMARY AND/OR RECOMMENDATION We recommend approval contingent upon the above items being addressed.