Loading...
HomeMy WebLinkAboutFYI - Country Manor Senior Living PUD Engineering Comments +�11 Planning Commission Agenda Item FYI c.1'ry()rZ S-1,.JoSE"'10E1 MEETING DATE: July 11, 2016 AGENDA ITEM: Country Manor Senior Living PUD Engineering Items SUBMITTED BY: Administration STAFF RECOMMENDATION: FYI only PREVIOUS PLANNING COMMISSION ACTION: BACKGROUND INFORMATION: Enclosed are the engineering comments provided by Westwood related to the Country Manor project as requested during the last meeting. ATTACHMENTS: Westwood engineering letter REQUESTED PLANNING COMMISSION ACTION: No action needed Westwood July 5, 2016 Judy Weyrens City Administrator City of St. Joseph PO Box 668 St. Joseph, MN 56374 Re: Country Manor Senior Living PUD File 8495.00 Dear Judy: 37011 12th SL Voll, `vuullte 206 St. Cloud, IMiN 156303 Fax (320) 253 8737 WesVvvaadps.coyn (800) �70-949115 Late on June 30, 2016 we received the comments from the City's Engineer dated June 24, 2016 and June 27, 2016. We would like to address each comment individually below: Memorandum dated June 27, 2016 Construction Plans 1. The proposed turn lane construction along CSAH 21 only includes a southbound right turn lane with Phase I construction. Sheet 3 must be updated (profile design, typical section, etc.) to reflect Stearns County Highway Department's permit requirement to construct all turn lanes with the proposed phase. Per our meeting on Friday July 1, the construction will only be occurring on the south side of CSAR 121 and we will add a typical section for that area. 2. Adjust the building pad on Lot 10, Block 3 to avoid the 50' wetland setback line. Illustrate building setback lines on the grading plan. This has been noted on the plan. 3. Construct apedestrian ramp and adjust trail alignment for the small trail approach at the southeast quadrant of the CSAH 121/Lanigan Ave intersection. This has been revised. 4. Add notes for adjusting existing gate valve boxes and extension stems at the intersection ofLanigan Ave and CSAH 121. Notes have been added. 5. Provide slope stabilization of the temporary pond inlet ditch at the Jade Road pond. Slope stabilization has been added. 6. Note proposed curb stop adjustments and grades for existing water service curb stops along Lanigan Avenue. A note has been added to adjust curb stop elevation to final grade at time of final home construction. The existing set of building services for Lots 7 and 8, Block 3 exist primarily on the adjacent lot. Correct the sewer service with bends within the right of way, and adjust the alignment of the water service (or tap a new water service). New sanitary sewer service taps shall be made utilizing 15 "x4" 1uM...lDnsdphn•ue d &~flurveyin g,& Engineering westwoodps„cam JOY 5, 2016 age 2 PVC wyes with gasket -by -gasket PVC repair couplings. These services have been adjusted as noted. 8. Note hydrantflange adjustments (f necessary). These have been noted. 9. Reference is made to exterior chimney seals on sanitary sewer manholes. Public Works staffprefer the molded HDPE UI barrier as noted on details STO-01 and STO-02. This note has been updated. 10. Correct plan note on Sheet 7 for water main diameter at Mulligan Loop (10 -inch vs. 8 -inch). This has been updated 11. The proposed line work on Sheet 7 at Mulligan Loop indicates (appropriately) proposed drain tile connections for future foundation drain connections. Provide notes, accordingly, for the proposed construction. Notes for storm sewer and draintile are on the Street and Storm Sewer P&P sheets. 12. Per Note 8 on Sheet 2, clam if the foundation drain tile system will include tracer wires. Clark the proposed diameters of the main perforated drain tile along the curb line on Lanigan Ave. Main diameters shall be larger than 4 -inch where they serve a combined role of street subgrade drain and building foundation connection. Annotate proposed diameters on the drawings accordingly. Note 8 has been revised; no tracer wires will be included because the cleanout will mark the location. Draintile has been noted as 6" under the street. Diameters are noted. 13. Verb the proposed RCP class for 12 -inch and 15 -inch storm drains as they are identified as Class 3 on the profile drawing on Sheet 8 and 9. Typically, in this diameter range, Class 5 pipe is provided as it has traditionally been the same material cost as Class 3 pipe. 12" and 15" RC pipe has been noted as Class 5. 14. Provide a concrete plug for the 42 -inch storm drain stub at Mulligan Loop. This has been added. 15. Verb the proposed 48 -inch diameter for structure CBMH-125. Preliminary computations suggest a 72 -inch structure is required. The diameter has been updated. 16. On sheet 9, verb the proposed storm drain profile downstream of STMH-115 and the existing water main profile. It would appear there will be a pipe crossing conflict. Watermain elevations have been updated per SEH's Record Drawings. 17. Clark the intentions for the existing 12 -inch CMP culvert at station 2+20 on Neary Street. This is an existing culvert. It will be removed and replaced. 18. Note on the drawings water main insulation where storm drainpipes cross the water main. Water service goose necks shall also be insulated. Insulation has been added. Water service goosenecks have 10 -feet of cover, and based on our July 1 meeting no additional insulation is needed on them. 19. Additional drawing detail is necessary at the outlet of FES -116. It is not clear how the proposed invert elevation matches the temporary pond geometry and elevation. Submit pipe flow JOY 5, 2016 age 3 characteristics at the outlet. Additional energy dissipation at the outlet (beyond Class III rip rap) would appear to be warranted. Notes have been added to the pian. 20. The proposed seeding rate for mix 25-151 is below recommended rates (per the 2014 MnDOT Seeding Manual). Boulevards within the public rights of way shall be restored with a minimum of 5 - inches of suitable topsoil meeting, at a minimum, the requirements ofMnDOT 3877.2F for Boulevard Topsoil Borrow. Our experience has shown the rate to be adequate. The topsoil specification has been noted in an addendum to Specification Section 2905 — 2.04. 21. Edit the pavement section identified on detail STR-09. The typical section forpublic bituminous trails shall include 2.5 -inches of SP9.5 wearing course mixture (SPWEA230C) over 6 -inches of Aggregate Base, Class V, and befog sealed with CSS -IH diluted. The City Detail has been revised. Specifications 22. Consider changing the correction period defined in the project manual from one year after the date of Substantial Completion to two years as the Developer's Agreement will require a two-year correction period. The correction period has been addressed with the addendum. 23. The aggregate base finished grade on the public streets shall be blue -topped. This has been added. 24. Tracer wires shall be terminated at tracer wire boxes (ex. Snake Pit by Copperhead Industries) and not directly wrapped around appurtenances (ex hydrants). This has been added. 25. Reference to Polyvinyl Chloride pipe or Polyethylene fittings shall be removed from the water main section. Ductile iron pipe and fittings are the only approved materials. This has been deleted. 26. Hydrant flags shall be Flexstake as detailed on the standard hydrant detail. Hydrant break -off traffic flange height shall be 22 -inches as detailed on the standard detail. This has been added. 27. Hydrants and water main shall have a minimum cover depth of 8 feet. This has been revised 28. Include standard detail WAT-10 which defines requirements for waterworks brass. This has been added to the pian. 29. See plan note 13 above relative to RCP sewer pipe classes for the smaller pipe diameters. This has been addressed. 30. The geotechnical report recommends the use of a "high strength geosynthetic " below all pavements with an additional 0.5 -inch in bituminous thickness and 2 inches in aggregate base thickness. While this recommendation was made for entrance areas, it would be relevant to the public streets too that deliver traffic to the entrance areas. The pavement section has been revised in the pians. Country Manor Campus Civil Engineering Drawings 31. Sheet C4.0: remove reference to PVC water main material. References to PCV watermain have been removed. 32. The utility plan proposes to install both a storm drain and (steel -encased) water main beneath the proposed building structure near the center of the site. While we are aware this type of installation JOY 5, 2016 a 4. has occurred elsewhere within the region, it is not an ideal. While we assume the owner understands the associated risks, we would recommend at least seeking the owner's acknowledgement. This is a common practice and the owner does not have an issue with this design. 33. The proposed sanitary sewer, prior to the connection to the public sewer system, shall be equipped with a system capable of screening and removing adult diapers, wipes, and similar solids from the waste stream. Submit further detail on the proposed system and location. At this time we believe it will be a screening process inside the building. The building's mechanical engineer is working on this design. 34. Provide insulation at water main crossings beneath the storm drain. Insulation has been added. 35. Sheet C5.0: additional stabilization and BMPs beyond seed and type I mulch should be identified, given the size of the site, and for the prominent ditch across the north side of the site. Additional stabilization and BMPs have been added to the plans. Memorandum Dated June 24, 2016 1. Comments provided during the review of the initial Hydrology Report dated 04/22/16, noted that if site constraints exist that limit the effectiveness of an infiltration system, then alternative treatment options should be considered with preference given to filtration techniques. Infiltration and/or filtration BMPs have not been incorporated into the Phase I design. Ponding was discussed at the July 1 meeting. 2. Rate control must be provided so post -development peak flow rates at each discharge point from the project shall not exceed pre -development peak flow rates for the 2, 10, and 100 year, 24-hour storm events. Runoff from the Phase I development routed to the East Culvert note does meet this requirement. This was discussed at the July 1 meeting. The desire is to reduce the discharge to the west culvert while not creating issues at the east culvert. Calculations have indicated issues will not arise. Options do existing if issues arise (discharge to east, increase size of culvert under CSAR 121, etc.). Additionally, the DA will be revised to include verbiage about the timing of phase 3 and the construction of east stormwater improvements. 3. Regional ponds must be designed with a 2 foot freeboard between the high water level from the largest required design storm event and the top of the pond. Ponds 1065 (NWApartment Site) and 3P (Jade Road Pond) do not meet this requirement. Pond 1065 is a local pond and not a regional pond. Jade Road Pond is an existing pond. This item has not be enforced when modifying existing ponds in our previous experiences in the City. 4. Information has not been provided verging that pond 105P meets the current NPDES wet pond requirements and the City of St. Joseph pond requirements. 105P is not a permitted wet pond under the NPDES permit. Per the July 1 meeting, we have added a detail showing the slopes and geometry. 5. An email dated 06/22/16 from Will Huston indicates conditional approval has been received from the Sauk River Watershed District and TSS and TP treatment information was sent to the Watershed District for review. Conditions of the approval, along with the TSS and TP treatment information, needs to be provided. This will be forwarded when completed. JOY 5, 2016 age 6. Energy dissipation at outlets shall be designed in accordance with MnDOT Design criteria. It is. 7. As indicated in a letter from Westwood Professionals dated 06/03/16, each phase will be permitted separately and, therefore, each future phase will need to be designed to meet the stormwater management requirements at the time it is permitted. This is the way the watershed wants it. 8. Future development identified on the plans indicate the future construction of an infiltration sand shelf within the Jade Road Pond. If/when the sand shelf is constructed, design information will be required to verb the sand shelf meets the NPDES infiltration requirements and is designed according to the MNStormwater Drainage Manual. This is on the preliminary plat and is subject to change. If infiltration is provided elsewhere (such as to the east with the phase 3 improvements), this shelf will not be needed. Enclosed are the revised plans and addendum. With the revisions and the supporting documents, we ask that the City approve the street construction and the site plans. Please contact me if you have any questions. Sincerely, WESTWOOD PROFESSIONAL SERVICES /001 Ye J, �4 William R. Huston, PE Land Market Leader CC: Mitch Rengel, CM St. Joe, LLC Corey Gerads, CM St. Joe, LLC Dan Tideman, GLTArchitects Randy Sabart, SEH Therese Haffner, City of St. Joseph