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CC Staff Report 9-29-05 CITY OF CHANHASSEN 7700 Market Boulevard PO Box 147 Chanhassen, MN 55317 Administration Phone 952.227.1100 Fax 952.227.1110 Building Inspections Phone: 952.227.1180 Fax: 952.227.1190 Engineering Phone 952.227.1160 Fax: 952.227.1170 Finance Phone 952.227.1140 Fax: 952.227.1110 Park & Recreation Phone: 952.227.1120 Fax: 952.227.1110 Recreation Center 2310 Coulter Boulevard Phone: 952.227.1400 Fax: 952.227.1404 Planning & Natural Resources Phone 952.227.1130 Fax: 952.227.1110 Public Works 1591 Park Road Phone: 952.227.1300 Fax: 952.227.1310 Senior Center Phone 952.227.1125 Fax 952.227.1110 Web Site www.ci.chanhassen.mn.us /1'" J -I .~,a: MEMORANDUM TO: Todd Gerhardt, City Manager FROM: Bob Generous, Senior Planner O~ DATE: September 29, 2005 SUBJ: Final Plat Approval for Chanhassen West Business Park Planning Case No. 05-23 PROPOSAL SUMMARY The applicant is requesting final plat approval for Chanhassen West Business Park creating 8 lots, 3 outlots and right-of-way for public streets. The proposal includes approximately 40 acres. The development complies with the Planned Unit Development Design Standards approved for the project. Staff is recommending approval of the final plat for Chanhassen West Business Park. City Council approval requires a majority of City Council present. BACKGROUND On August 22, 2005 the Chanhassen City Council approved the following: The ordinance Rezoning the property located within the Chanhassen West Business Park from Agricultural Estate District (A2) to Planned Unit Development (PUD) incorporating the development design standards contained within the staff report, as modified by City Council; The Preliminary Plat for Chanhassen West Business Park, plans prepared by Schoell & Madson, Inc., dated June 17,2005, subject to conditions; And, The Wetland Alteration Permit to fill and alter wetlands within the development, plans prepared by'Schoell & Madson, Inc., dated June 17,2005, subject to conditions. FINAL PLAT REVIEW PROPOSAL SUMMARY The applicant is requesting final plat approval for 8 lots, 3 outlots and right-of- way for public streets. As part of the preliminary plat review, the City approved a wetland alteration permit and rezoning of the property to Planned Unit Development. The City 01 Chanhassen . A growing community with clean lakes, quality schools, a charming downtown, thriving businesses, winding trails, and beautiful parks. A great place to live, work, and play. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 2 of22 The proposal meets the requirements of the PUD Development Design Standards and is recommended for approval. GRADINGIDRAINAGEIEROSION CONTROL The existing site is about 44.75 acres in size with scattered wetlands. In addition, there are three existing buildings on the property which will have to be razed prior to any grading operations. The current plans show buildings with proposed floor elevations from 961-966. The applicant is now proposing to grade about 83% of the site for the new building pads, storm pond, and a proposed street ending with a cul-de-sac. The current plans propose eight lots located along the proposed street and cul-de-sac. There are a few areas of concern with the grading plan. Staff would like to see the applicant do a better job of matching in with the existing topography of the site and maintain a side slope of 3: 1 maximum. The existing site drains toward the existing three wetlands on the northwesterly and southwesterly comers and east side of the parcel. At these elevations, stormwater from the buildings and parking lots will drain toward the proposed catch basins and be conveyed via storm sewer system to the proposed storm pond on the southwesterly comer of the parcel. The pond will treat the water before discharging it to the adjacent wetland. Staff recommends that the swale west of Lot 4 be filled in to reduce the height of or eliminate the need for a retaining wall at this location. In order to do this, the developer must ensure that the off-site run off from the west is diverted. All of the ponds are required to be designed to National Urban Runoff Program (NURP) standards with maximum 3:1 slopes and a 10:1 bench at the NWL. The applicant is required to meet the existing site runoff rates for a lO-year and lOO-year, 24-hour storm event. Storm sewer sizing calculations must be submitted at the time of final plat application. The storm sewer must be sized for a lO-year, 24-hour storm event. Drainage and utility easements must be dedicated on the final plat over the public storm drainage system including ponds, drainage swales, and wetlands up to the lOO-year flood level. The interior lot storm sewer will require private easements to be dedicated where the sewer crosses from one lot to another. The applicant must be aware that a retaining wall structure is not allowed within the public street right-of-way. Also, any retaining wall exceeding four feet in height must be designed by a registered structural engineer with approved safety fence and a building permit must be obtained. Erosion control measures and site restoration must be developed in accordance with the City's Best Management Practice Handbook (BMPH). Staff recommends that the City's Type II erosion control fence, which is a heavy duty silt fence, be used for the area adjacent to the existing wetlands on the north and south grading limits of the site. Type I silt fence shall be used in all other areas. In addition, tree preservation fencing must be installed at the limits of tree removal. Erosion control blankets are recommended for all of the steep 3: 1 slopes with an elevation change of eight feet or more. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 3 of22 All disturbed areas, as a result of construction, must be seeded and mulched or sodded immediately after grading to minimize erosion. The applicant should be aware that any off-site grading will require an easement from the appropriate property owner. If importing or exporting material for development of the site is necessary, the applicant will be required to supply the City with detailed haul routes. A minimum 75-foot rock construction entrance must be added to the plans at the proposed access off of Galpin Boulevard. UTILITIES Municipal sewer and water stubs are available to the site from Galpin Boulevard on the east side of the parcel. The applicant is proposing to connect to the existing utility stubs and extend them to the proposed lots to service the site. The sanitary and watermain lines that run within the public street right-of-way and within the shared driveway between Lots 4 and 5 until the last sanitary manhole will be considered a public utility line and the remaining will be considered private utility. Additional gate valves are needed for the shared private watermain between any two lots. Minimum 20-foot wide easements will be required over the public portion of the storm sewer lines between Lots 2 and 3. The underlying property has been previously assessed for sewer, water and street improvements and there is no remaining assessment due payable to the City. Since the developer will be responsible for extending lateral sewer and water service to the lots, the sanitary sewer and water connection charges will be waived. The sanitary sewer and water hookup charges will be applicable for each of the new lots. The 2005 trunk hookup charge is $1,458 for sanitary sewer and $2,955 for watermain. Sanitary sewer and watermain hookup fees may be specially assessed against the parcel at the time of building permit issuance. All of the utility improvements are required to be constructed in accordance with the City's latest edition of Standard Specifications and Detail Plates. Upon completion of the utility improvements, the utilities will be turned over to the City for maintenance and ownership. The applicant is also required to enter into a development contract with the City and supply the necessary financial security in the form of a letter of credit or cash escrow to guarantee installation of the improvements and the conditions of final plat approval. Permits from the appropriate regulatory agencies will have to be obtained, including but not limited to the MPCA, Department of Health, Watershed District, Carver County, MnDOT, etc. STREETS The proposed development lies west of Galpin Boulevard (CSAH 19) and north of Lyman Boulevard (CSAH 18), A-Minor Expander Arterials as identified on SRF Consulting Group Incorporated's Functional Classification Map. Upon City Council approval of the September 29,2005 Consent Agenda, the development is subject to the $3,600/developable acre Arterial Collector Fee. All new developments along the Lyman Boulevard corridor are subject to this fee. The proceeds of this fee will fund the Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 4 of 22 reconstruction of Lyman Boulevard between Audubon Road and Powers Boulevard. The Arterial Collector Fee is calculated as follows: 40.15 acres (gross area) - 4.147 acres (area of Outlot A) - 2.125 acres (area of Outlot B) x $3,600/acre = $121,960.80 Proposed access to the site will be from Galpin Boulevard, which aligns with Stone Creek Drive, an existing local street extending east of Galpin Boulevard. Staff has researched the feasibility of moving the proposed site access from Galpin Boulevard to Lyman Boulevard in response to citizens' requests. Due to wetland conditions, any access from the site to Lyman Boulevard would be 1,000 feet west of Galpin Boulevard. Carver County has identified Lyman Boulevard as a regional east-west collector with limited access; therefore staff recommends that the access to Chanhassen West Business Park remain at the Galpin Boulevard/Stone Creek Drive intersection. This recommendation is also consistent with Section 18-57 of the City Code, which states that "access to arterial streets shall be at intervals of not less' than one-fourth mile [1,320 feet] and through existing and established crossroads". The developer's traffic engineer, TDI, completed an analysis of traffic and determined that right- in, right-out access from Lyman Boulevard to the site would not significantly reduce the number of vehicles using the Galpin Boulevard access. Based on TDI's findings, a right-in, right-out access on Lyman Boulevard is not proposed. SRF Consulting Group, Inc. analyzed the 2020 transportation system in conjunction with the City's 2020 Comprehensive Plan. SRF's forecasted 2020 traffic volume for Galpin Boulevard was based on the 2020 Land Use Map and the construction of the new Trunk Highway 212. The proposed land use of the Chanhassen West Business Park is consistent with the 2020 land use used in SRF's traffic analysis. SRF's report does not identify a need to upgrade Galpin Boulevard by the year 2020. I Right turn lanes for north and southbound traffic exist at the Galpin Boulevard intersection with Stone Creek Road and the proposed site access. The developer must submit an access permit to Carver County Public Works for the proposed connection to Galpin Boulevard. As stipulated by the Assistant County Engineer, the developer must submit information on proposed turn lanes with the permit application. There is one public street proposed with the project. The street is proposed as a cul-de-sac running west of Galpin Boulevard and a private shared driveway between Lots 4 and 5. The applicant is proposing the paved streets to be 32-feet wide with a 60-foot wide right-of-way and a 46-foot cul-de-sac paved radius. The applicant must be aware that the City's standard commercial street pavement width is 36-foot wide from back-of-curb to back-of-curb and the cul-de-sac must be 48-foot in radius. Staff is fine with the 24-foot wide shared driveway between Lots 4 and 5. The developer will be required to submit inspection/soil reports certifying that the private streets were built to a 7-ton design. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 5 of 22 Staff has concerns of movements of truck traffic accessing off Galpin Boulevard to Lots 1 and 8 being too close. Staff recommends increasing the access width to 44 feet to create a three lane access off Galpin Boulevard and increase the turning curb radius. Also, relocate Lots' 1 and 8 easterly accesses further to the west and re-align them opposite of each other. The applicant should be aware that, in commercial districts, six-foot wide sidewalks are required and the parking driveway aisle must be 26-feet wide. Cross-access easements will be obtained for the shared driveways and recorded against the lots. PARKS AND RECREATION Comprehensive Park Plan The proposed Chanhassen West Business Park developmentis located within an area that is outside the municipal park service boundaries of Stone Creek Park and the Chanhassen Nature Preserve. The development shall pay full park fees "in force at the time of final plat approval in the amount of $359,500 (35.95 x $10,000 per acre). Parks fees for 2005 are $lO,OOO.per acre. Comprehensive Trail Plan The site does not contain any portion of the City's trail plan. A sidewalk connection to the trails in Galpin Boulevard is proposed as part of the development. LANDSCAPING The applicant does not meet minimum requirements for the buffer yards along the south and east property lines. Staff recommends that buffer yard plantings be increased in these areas to meet . minimum requirements. The applicant has saved a large portion of the existing, mature oaks on site. This preservation will add a unique feel to the site and proved the residential neighborhood to the north an added buffer for the development. The applicant did an excellent job fitting the design to the site. COMPLIANCE TABLE Area (SQ. ft.) Frontage (ft.) Depth (ft.) Notes Code 43,560 150 200 Lot 1, Elk 2 166,233 328 354 Lot 2, Elk 2 144,036 238 354 Lot 3, Elk 2 124,349 329 350 Wetland setback Lot 4, Elk 2 219,215 35 # 380 Wetland setback Lot 5, Elk 2 156,190 75 @ 404 Wetland setback Lot 3, Blk 1 257,813 80@ 460 North buffer yard Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 6 of 22 Area (SQ. ft.) Fronta~e (ft.) Depth (ft.) Notes Lot 2, Blk 1 82,385 205 366 Lot 1, Blk 1 97,843 328 368 Outlot A 180,643 Ponding and wetland mitigation Outlot B 92,577 Wetland Outlot C 165,365 Preserved woodlands ROW 62,069 1.42 acres Total 1,748,718 40.15 acres # Lot must be revised to meet the minimum 60 feet frontage on cul-de-sac. @ Exceeds the 60 feet frontage on cul-de-sac. REVIEW CONDITIONS OF APROV AL 1. Applicant shall increase landscape plantings in the south and east property line bufferyards to meet minimum requirements. A revised landscape plan shall be submitted before final approval. * This condition still applies. 2. Tree protection fencing shall be installed prior to any construction activities. Fencing shall remain in place until construction is completed. * This condition still applies. 3. All trees shown as preserved on plans dated 6/17/05 shall be protected. Any trees damaged or removed shall be replaced at a rate of 2: 1 diameter inches. * This condition still applies. 4. Wetland replacement shall occur in a manner consistent with the Minnesota Wetland Conservation Act (MR 8420). A Minnesota Local/State/Federal Application Form for WaterIWetland Projects (Parts I and II) shall be submitted for the proposed project. The application shall include sequencing discussions and sequencing flexibility requests, if applicable. The applicant must receive approval of a wetland replacement plan prior to or concurrent with final plat approval and prior to wetland impacts occurring. * This condition has been partially met and can be modified as follows: Wetland replacement shall occur in a manner consistent with the Minnesota Wetland Conservation Act (MR 8420). f~ Mill1l8s8ta L88al.'Stat€l.lf'8€l8ral A~~ligati8fi F8fm. fur 'J,'at@f.'V.'8tlOO€l Pr@j8€1ts (PaRS I all€l II) sRall B@ sNBmitt8€l f8f tRg ~f8~88g€l ~f€~j88t. TR8 ~~li€1ati811 sRaH Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 7 of 22 i'H~h:l€h~ 8€H1tl@ll@illg 8i8@tl88i€l1l8 008 8@t}ti@Il@illg thmibilit~,. r@~tl@8t8, if ~Fli@ool@. The applicant must receive approval of a wetland replacement plan prior to or concurrent with final plat approval and prior to wetland impacts occurring. 5. A wetland buffer 16.5 to 20 feet in width (with a minimum average of 16.5 feet) shall be maintained around all wetlands and proposed wetland mitigation areas. Wetland buffer areas shall be preserved, surveyed and staked in accordance with the City's wetland ordinance. The applicant shall install wetland buffer edge signs, under the direction of City staff, before construction begins and must pay the City $20 per sign. All structures (including parking lots) shall maintain a 40-foot setback from the edge of the wetland buffer. * This condition still applies. 6. The applicant shall submit a letter of credit equal to 110% of the cost of the wetland creation (including grading and seeding) to ensure the design standards for the replacement wetland are met. The letter of credit shall be effective for no less than five years from the date of final plat approval. The applicant shall submit a cost estimate for wetland creation (including grading and seeding) so the City can calculate the amount of the wetland creation letter of credi t. * This condition still applies. 7. The proposed development shall maintain existing runoff rates and meet NURP standards. Storm water calculations shall be submitted to ensure the proposed storm water pond is sized adequately for the proposed development. * This condition has been met. 8. Stable emergency overflows shall be provided for the proposed pond on site. The emergency overflows shall be clearly labeled on the plan and a detail is needed. The emergency overflows may be stabilized with a turf re-enforcement mat or fabric and riprap. * This condition still applies. 9. Notes on the plan describing timing of temporary stabilization with Type 1 mulch and seed or erosion control blanket and seed shall be included. The notes shall include timing of stabilization as well as the rate of mulch application (2 tons per acre, disc anchored). * This condition still applies. 10. All riprap/fabric at the flared end section shall be installed within 24 hours of flared end section installation. * This condition still applies. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 8 of 22 11. Erosion control blanket shall be installed on all slopes greater than or equal to 3: 1. All exposed soil areas shall have temporary erosion protection or permanent cover year round, according to the following table of slopes and time frames: Type of SlolJe Steeper than 3: 1 10:1 to 3:1 Flatter than 10: 1 Time 7 days 14 days 21 days (Maximum time an area can remain open when the area is not actively being worked.) These areas include constructed storm water management pond side slopes, and any exposed soil areas with a positive slope to a storm water conveyance system, such as a curb and gutter system, storm sewer inlet, temporary or permanent drainage ditch or other natural or man made systems that discharge to a surface water. * This condition still applies. 12. Erosion control blanket shall be specified in the swale from the flared end section to the wetland along the west boundary of the site. The blanket specified shall adequately protect the area from designed velocity and depth of flow. The blanket and seed in the swale shall be installed within 5 days of culvert installation. Erosion control blanket is recommended for the pond slopes from around 952 to 942 contours. All blanket on the plan shall be shown as a shaded area. * This condition still applies. 13. Temporary sediment basins shall be installed prior to disturbing upslope areas. The areas of temporary sediment basins shall be labeled on the plan. A temporary outlet (e.g., a perforated riser and rock cone) shall be provided for the pond; details should be provided. Temporary basins shall be constructed in the area of the proposed permanent storm water pond, the southeast comer of the site prior to discharging to the culvert under Galpin Boulevard, and possibly in the northwest area of the site to handle water runon from the north prior to discharge to the wetland. * This condition still applies. 14. Any and all area inlets or drop inlets in paved areas shall be protected with alternate controls/Wimco details. The engineer shall research and provide alternate designs for Wimco-type inlet controls to fit the various types of inlets. * This condition still applies. 15. Additional inlet controls shall be provided for adjacent inlets on Galpin Boulevard and Street A. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 9 0122 * This condition shall be modified as follows: Additional inlet controls shall be provided for adjacent inlets on Galpin Boulevard and Galpin Court. 16. Silt fence shall be installed around Outlot A along the east side between the pond and the wetland. * This condition still applies. 17. Type 1 and Type 2 silt fence locations shall be specified on the plan. Type 2 silt fence shall be installed around all wetland areas and in the southeast comer of the site to protect the culvert under Galpin Boulevard. The silt fence shall be extended along the south side to close the gap in the silt fence. * This condition still applies. 18. Street cleaning of soil tracked onto public streets shall include daily street scraping and street sweeping as-needed. * This condition still applies. 19. The estimated total SWMP fee, due payable to the City at the time of final plat recording, is $413,661. * This condition shall be modified as follows: The @8tim&t@€l total SWMP fee, due payable to the City at the time of final plat recording, is $113,(;(;1 301,493.29. 20. The applicant shall apply for and obtain permits from the appropriate regulatory agencies (e.g., Carver County, Minnesota Pollution Control Agency (NPDES Phase II construction permit), Minnesota Department of Natural Resources (for dewatering), Army Corps of Engineers) and comply with their conditions of approval. * This condition still applies. 21. In lieu of parkland dedication and trail construction, full park fees shall be collected at the rate in force at the time of final plat for the proposed Chanhassen West Business Park. At current rates, the park fee would total $359,500 (35.95 x $10,000 per acre). * This condition still applies. 22. A demolition permit must be obtained before beginning demolition of any existing structures. * This condition still applies. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 100122 23. Retaining walls over four high must be designed by a professional engineer and a permit must be obtained prior to construction. * This condition is a duplicate of condition 38 and shall be deleted. 24. Provide a water service for Lot 6. * This condition has been met. 25. A lO-foot clear space must be maintained around fire hydrants i.e., street lamps, trees, shrubs, bushes, Xcel Energy, Qwest, cable TV and transformer boxes. This is to ensure that fire hydrants can be quickly located and safely operated by firefighters. Pursuant to Chanhassen City Ordinance #9-1. * This condition still applies. 26. Fire apparatus access roads and water supplies for fire protection is required to be installed. Such protection shall be installed and made serviceable prior to and during the time of construction except when approved alternate methods of protection are provided. * This condition still applies. 27. The new proposed street will be required to have a street name. Submit proposed street name to Chanhassen Building Official and Chanhassen Fire Marshal for review and approval. * This condition has been met. The proposed street name is Galpin Court. 28. No burning permits will be issued for trees to be removed. Trees and shrubs must either be removed from site or chipped. * This condition still applies. 29. Fire apparatus access roads shall be designed and maintained to support the imposed load of fire apparatus and shall be surfaced so as to provide all weather driving capabilities. Pursuant to Minnesota Fire code Section 503.2.3. * This condition still applies. 30. Temporary street signs shall be installed on street intersections when construction of a new roadway allows passage be vehicles. Pursuant to 2002 Minnesota fire code Section 501.4. * This condition still applies. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 11 of22 31. Prior to final platting, storm sewer design data will need to be submitted for staff review. Depending on the size of the drainage area, additional catch basins may be required at that time. The storm sewer will have to be designed for a lO-year, 24-hour storm event. Drainage and utility easements will need to be dedicated on the final plat over the public storm drainage system including storm water ponds, drainage swales, emergency overflows, access routes for maintenance, over all existing wetlands, wetland mitigation areas, and buffer areas used as PVC. The minimum easement width shall be 20 feet wide. * This condition shall be modified as follows: Prior to filial ~lattilig construction, storm sewer design data will need to be submitted with drainage map for staff review. Depending on the size of the drainage area, additional catch basins may be required at that time. The storm sewer will have to be designed for a lO-year, 24-hour storm event. Drainage and utility easements will need to be dedicated on the final plat over the public storm drainage system including storm water ponds, drainage swales, emergency overflows, access routes for maintenance, over all existing wetlands, wetland mitigation areas, and buffer areas used as PVC. The minimum easement width shall be 20"feet wide. 32. The interior lot storm sewer will require private easements to be dedicated where the sewer crosses from one lot to another. * This condition still applies. 33. Private utility easements are required for the sanitary sewer and water lines that serve Lot 4 but go through Lot 5. * This condition shall be modified as follows: PF:i::ate Mtilit~/ eaSi:HRelits &fS fS€Juifsd {Sf tke 8&1iitary SS!::Sf &lid '::atsf liligs that ssr:g Lst 4 1mt gs tkfSMgk Lst 5. Show minimum 30- foot utility easement between Lots 4 and 5 along the private driveway from sanitary MH #6 to MH #8. 34. The sanitary sewer and water hookup charges will be applicable for each of the new lots. The 2005 trunk hookup charge is $1,458 for sanitary sewer and $2,955 for watermain. Sanitary sewer and watermain hookup fees may be specially assessed against the parcel at the time of building permit issuance. * This condition still applies. 35. On the site plan: a. Revise the cul-de-sac pavement radius to 48 feet. b. Revise the parking driveway aisle from 24 feet to 26 feet wide. c. Revise the public street width from 32 feet to 36 feet wide. d. Increase the full access width off Galpin Boulevard to 44 feet and create three lane access. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 12 of22 e. Shift Lots 1 and 8 easterly access further toward the west and realign the across each other. f. Show at least one, 6-foot wide, side walk along the public street. g. Show the access off Galpin Boulevard turning curb radius. h. Realign lot 5 access perpendicular to the shared driveway. 1. Show street lights. J. Show handicap parks and ramps. * This condition shall be modified as follows: On the site plan: a. Revise the cul-de-sac pavement radius to 48 feet. b. Revise the parking driveway aisle from 24 feet to 26 feet wide. c. Revise the public street width from 32 feet to 36 feet wide. d. Increase the full access width off Galpin Boulevard to 44 feet and create three lane access. e. . Shift Lots 1 and 8 easterly access further toward the west and realign them across from each other. f. Show at least one, 6-foot wide, side walk along the public street and pedestrian curb ramps. g. Show the access off Galpin Boulevard turning curb radius. h. Realign lot 5 access perpendicular to the shared driveway. 1. ~k€J!;: 8tF@~t ligHt8. J. Show handicap parksing spots and ramps. k. Show concrete driveway apron at every lot access per detail #5207. 36. On the grading plan: a. Extend silt fence type between the storm pond and Outlot A. Silt fence Type IT must be used adjacent to wetlands and storm pond. b. Revise contour lines to match 3: 1 maximum slope and tie the proposed contour lines with the existing contours for Lots 4, 5, south of Lot 2 and northeast of Lot 1, Block 2. c. Show the proposed contour lines for Lot 6. d. Show all retaining walls top and bottom elevations. e. Show all emergency overflows (EOF). The EOF must be 1.5' lower than the adjacent lowest floor. f. Revise Lot 6 parking slope to 0.7% minimum. g. Add a note to remove any existing structure and access off Galpin Boulevard and all disturbed areas, as a result of construction, must be seeded and mulched or sodded immediately after grading to minimize erosion. h. Show 75-foot minimum construction rock entrance. 1. No retaining walls structure is allowe~ within public street and/or public utility easements, revise accordingly. J. Show 20-foot utility easement for the storm sewer between Lots 2 and 3 k. Show contour lines for the berm on Outlot B. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 13 of22 * This condition shall be modified as follows: On the grading plan: a. Extend silt fence ~ between the storm pond and Outlot A. Silt fence Type II must be used adjacent to wetlands and storm pond. b. Revise contour lines to match 3: 1 maximum slope and tie the proposed contour lines with the existing contours for Lots 4, 5, Block 2, south of Lot 2, Block 2, and northeast of Lot 1, Block 2. c. Show the proposed contour lines for Lot 6. d. Show all retaining walls top and bottom elevations. e. Show all emergency overflows (EOF). The EOF must be 1.5' lower than the adjacent lowest floor. f. Revise Lot @. 3, Block 1 parking slope to 0.7% minimum. g. Add a note to remove any existing structure and access off Galpin Boulevard and Lyman Boulevard. A811 disturbed areas, as a result of construction, must be seeded and mulched or sodded immediately after grading to minimize erosion. h. Show 75-foot minimum construction rock entrance. 1. No retaining walls structure is allowed within public street and/or public utility easements, revise accordingly. J. ~h8';: 29 f88t \:ltility @aS€HluHit fur the St8Fm s@!,':@r e@t'::@@R L8t8 2 aft€! 3. k. Show contour lines for the berm on Outlot B. 37. On the utility plans: a. Show all existing and proposed drainage and utility easements. b. Show the proposed sanitary and storm sewer stubs inverts. c. Add storm sewer schedule. d. Public storm sewer pipe type must be RCP and IS-inch minimum diameter. e. The last street accessible storm manhole (STMH#2) must be built with a sump. f. Revise sanitary sewer pipe from DIP to PVC-C900. g. On the utility profile show all sewer and pipe crossings. h. Minimum vertical separation must be 18 inches between watermain and sewer. 1. Call out watermain fittings * This condition shall be modified as follows: On the utility plans: a. Show all @RistiRg aft€! 20-foot proposed drainage and utility easements between Lots 2 and 3, Block 2. b. Show the proposed sanitary and storm sewer stubs inverts. c. Add storm sewer schedule. d. Public storm sewer pipe type must be RCP and IS-inch minimum diameter. e. The last street accessible storm manhole (STMH#2A) must be built with a sump. f... R@':is@ saftitary s@'::@r pipe fr8m DIP t8 P'.'C C~99. g. On the utility profile show all sewer and pipe crossings. h. Minimum vertical separation must be 18 inches between watermain and sewer. 1. Call out watermain fittings. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 14 of22 j. Add the outlet control structure per detail #3109. 38. Any retaining wall over four feet in height must be designed by a registered Civil Engineer in the state of Minnesota with an approved safety fence on top of it. Also, it will require a building permit from the Building Department. * This condition still applies. 39. Add the following City of Chanhassen Detail Plate Nos. 1002,2109,21102204,3104,3109, 5201,5205,5214 and 5215. * This condition shall be modified as follows: Add the following City of Chanhassen latest Detail Plate Nos. 1001, 1002, 1003,2109,2110,2201,2204,2205, 3104,~, 5201, 5205, 5214, aOO 5215, 5216, 5217, 5221, 5232, 5240,5241,5242,5302 and 5313. 40. Prior to final plat approval, a professional civil engineer registered in the state of Minnesota must sign all plans. * This condition still applies. 41. All of the ponds are required to be designed to National Urban Runoff Program (NURP) standards with maximum 3:1 slopes and a 10:1 bench at the NWL. * This condition shall be modified as follows: All sf tlH~ Storm ponds ftf8 is required to be designed to National Urban Runoff Program (NURP) standards with maximum 3: 1 slopes and a 10: 1 bench at the NWL. Submit drainage calculations for staff review. 42. Cross-access easements for the shared driveway accesses must be obtained and recorded against the lots for each of the entrance drives. * This condition still applies. 43. Any off-site grading will require easements from the appropriate property owner. * This condition still applies. 44. Public utility improvements will be required to be constructed in accordance with the City's latest edition of Standard Specifications and Detail Plates. Detailed construction plans and specifications will be required at the time of final platting. The applicant will also be required to enter into a development contract with the City and supply the necessary financial security in the form of a letter of credit or cash escrow to guarantee installation of the improvements and the conditions of final plat approval. The applicant must be aware that all public utility improvements will require a preconstruction meeting before building permit issuance. Permits from the appropriate regulatory agencies must be obtained, including but Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 15 of22 not limited to the MPCA, Department of Health, Watershed District, Carver County, MnDOT, etc. * This condition still applies. 45. If importing or exporting material for development of the site is necessary, the applicant will be required to supply the City with detailed haul routes and traffic control plans. The applicant should be aware that any off-site grading will require an easement from the appropriate property owner. * This condition still applies. 46. All private streets are required to have 24-foot wide paved streets from back-of-curb to back- of-curb, be built to a 7-ton design and contained within a 40-foot wide private easement. At the completion of the project, the developer will be required to submit inspection/soil reports certifying that the private streets were built to a 7-ton design. * This condition shall be modified as follows: All private streets are required to have ~ 26- foot wide paved streets from back-of-curb to back-of-curb, be built to a:+ 9-ton design and contained within a 40-foot wide private easement. At the completion of the project, the developer will be required to submit inspection/soil reports certifying that the private streets were built to a 7 9-ton design. 47. Six-foot wide sidewalks are required. * This condition has been met. 48. All of the proposed building pads must have a rear yard elevation at least three feet above the HWL of the adjacent ponds. * This condition still applies. 49. Installation of the private utilities for the site will require permits and inspections through the City's Building Department. * This condition still applies. 50. Comply with Carver County memo dated June 28, 2005 and revise the plans accordingly. * This condition still applies. 51. Revise plan sheet size to 24 x 36 using scale 50. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 16 of22 * This condition still applies. 52. The developer shall dedicate a permanent conservation easement over Outlot C. * This condition still applies. 53. The applicant shall work with staff to resolve any drainage issues along Lots 5, 6 and Outlot C. * This condition still applies. 54. The developer shall construct a berm within the 16 foot setback outside the wetland buffer zone on Lot 5. * This condition still applies. In addition, based on the review of the final development plans, staff recommends that the following conditions be added: 1. Revise the construction plans to correspond with the final plat lot designations. 2. Approval of the final plat is contingent upon approval of final construction plans/specifications for the project along with the developer entering into a development contract with the City and supplying the necessary financial security and fees. 3. The developer shall pay the $121,960.80 Arterial Collector Fee. 4. The developer shall work with the City of Chaska to accommodate storm water from properties to the west of the project. RECOMMENDA TION Staff recommends that the City Council adopt the following motion: "The Chanhassen City Council approves the Final Plat for Chanhassen West Business Park creating 8 lots, 3 outlots and associated right-of-way for public streets (plans prepared by Schoell & Madson, Inc., dated September 6, 2005), subject to the following conditions: 1. Applicant shall increase landscape plantings in the south and east property line bufferyards to meet minimum requirements. A revised landscape plan shall be submitted before final approval. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 17 of22 2. Tree protection fencing shall be installed prior to any construction activities. Fencing shall remain in place until construction is completed. 3. All trees shown as preserved on plans dated 6/17/05 shall be protected. Any trees damaged or removed shall be replaced at a rate of 2: 1 diameter inches. 4. Wetland replacement shall occur in a manner consistent with the Minnesota Wetland Conservation Act (MR 8420). The applicant must receive approval of a wetland replacement plan prior to or concurrent with final plat approval and prior to wetland impacts occurring. 5. A wetland buffer 16.5 to 20 feet in width (with a minimum average of 16.5 feet) shall be maintained around all wetlands and proposed wetland mitigation areas. Wetland buffer areas shall be preserved, surveyed and staked in accordance with the City's wetland ordinance. The applicant shall install wetland buffer edge signs, under the direction of City staff, before construction begins and must pay the City $20 per sign. All structures (including parking lots) shall maintain a 40-foot setback from the edge of the wetland buffer. 6. The applicant shall submit a letter of credit equal to 110% of the cost of the wetland creation (including grading and seeding) to ensure the design standards for the replacement wetland are met. The letter of credit shall be effective for no less than five years from the date of final plat approval. The applicant shall submit a cost estimate for wetland creation (including grading and seeding) so the City can calculate the amount of the wetland creation letter of credi t. 7. Stable emergency overflows shall be provided for the proposed pond on site. The emergency overflows shall be clearly labeled on the plan and a detail is needed. The emergency overflows may be stabilized with a turf re-enforcement mat or fabric and riprap. 8. Notes on the plan describing timing of temporary stabilization with Type 1 mulch and seed or erosion control blanket and seed shall be included. The notes shall include timing of stabilization as well as the rate of mulch application (2 tons per acre, disc anchored). 9. All riprap/fabric at the flared end section shall be installed within 24 hours of flared end section installation. 10. Erosion control blanket shall be installed on all slopes greater than or equal to 3: 1. All exposed soil areas shall have temporary erosion protection or permanent cover year round, according to the following table of slopes and time frames: Type of Slope Steeper than 3: 1 10:1 to 3:1 Flatter than 10: 1 Time 7 days 14 days 21 days (Maximum time an area can remain open when the area is not actively being worked.) Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 180122 These areas include constructed storm water management pond side slopes, and any exposed soil areas with a positive slope to a storm water conveyance system, such as a curb and gutter system, storm sewer inlet, temporary or permanent drainage ditch or other natural or man made systems that discharge to a surface water. 11. Erosion control blanket shall be specified in the swale from the flared end section to the wetland along the west boundary of the site. The blanket specified shall adequately protect the area from designed velocity and depth of flow. The blanket and seed in the swale shall be installed within 5 days of culvert installation. Erosion control blanket is recommended for the pond slopes from around 952 to 942 contours. All blanket on the plan shall be shown as a shaded area. 12. Temporary sediment basins shall be installed prior to disturbing upslope areas. The areas of temporary sediment basins shall be labeled on the plan. A temporary outlet (e.g., a perforated riser and rock cone) shall be provided for the pond; details should be provided. Temporary basins shall be constructed in the area of the proposed permanent storm water pond, the southeast corner of the site prior to discharging to the culvert under Galpin Boulevard, and possibly in the northwest area of the site to handle water runon from the north prior to discharge to the wetland. 13. Any and all area inlets or drop inlets in paved areas shall be protected with alternate controls/Wimco details. The engineer shall research and provide alternate designs for Wimco-type inlet controls to fit the various types of inlets. 14. Additional inlet controls shall be provided for adjacent inlets on Galpin Boulevard and Galpin Court. 15. Silt fence shall be installed around Outlot A along the east side between the pond and the wetland. 16. Type 1 and Type 2 silt fence locations shall be specified on the plan. Type 2 silt fence shall be installed around all wetland areas and in the southeast corner of the site to protect the culvert under Galpin Boulevard. The silt fence shall be extended along the south side to close the gap in the silt fence. 17. Street cleaning of soil tracked onto public streets shall include daily street scraping and street sweeping as-needed. 18. The total SWMP fee, due payable to the City at the time of final plat recording, is $301,493.29. 19. The applicant shall apply for and obtain permits from the appropriate regulatory agencies (e.g., Carver County, Minnesota Pollution Control Agency (NPDES Phase IT construction permit), Minnesota Department of Natural Resources (for dewatering), Army Corps of Engineers) and Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 19 of22 comply with their conditions of approval. 20. In lieu of parkland dedication and trail construction, full park fees shall be collected at the rate in force at the time of final plat for the proposed Chanhassen West Business Park. At current rates, the park fee would total $359,500 (35.95 x $10,000 per acre). 21. A demolition permit must be obtained before beginning demolition of any existing structures. 22. A lO-foot clear space must be maintained around fire hydrants i.e., street lamps, trees, shrubs, bushes, Xcel Energy, Qwest, cable TV and transformer boxes. This is to ensure that fire hydrants can be quickly located and safely operated by firefighters. Pursuant to Chanhassen City Ordinance #9-1. 23. Fire apparatus access roads and water supplies for fire protection is required to be installed. Such protection shall be installed and made serviceable prior to and during the time of construction except when approved alternate methods of protection are provided. 24. No burning permits will be issued for trees to be removed. Trees and shrubs must either be removed from site or chipped. 25. Fire apparatus access roads shall be designed and maintained to support the imposed load of fire apparatus and shall be surfaced so as to provide all weather driving capabilities. Pursuant to Minnesota Fire code Section 503.2.3. 26. Temporary street signs shall be installed on street intersections when construction of a new roadway allows passage be vehicles. Pursuant to 2002 Minnesota fire code Section 501.4. 27. Prior to construction, storm sewer design data will need to be submitted with drainage map for staff review. Depending on the size of the drainage area, additional catch basins may be required at that time. The storm sewer will have to be designed for a lO-year, 24-hour storm event. Drainage and utility easements will need to be dedicated on the final plat over the public storm drainage system including storm water ponds, drainage swales, emergency overflows, access routes for maintenance, over all existing wetlands, wetland mitigation areas, and buffer areas used as PVC. The minimum easement width shall be 20 feet wide. 28. The interior lot storm sewer will require private easements to be dedicated where the sewer crosses from one lot to another. 29. Show minimum 30-foot utility easement between Lots 4 and 5, Block 2 along the private driveway from sanitary MH #6 to MH #8. 30. The sanitary sewer and water hookup charges will be applicable for each of the new lots. The 2005 trunk hookup charge is $1,458 for sanitary sewer and $2,955 for watermain. Sanitary sewer and watermain hookup fees may be specially assessed against the parcel at the time of Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 20 of 22 building permit issuance. 31. On the site plan: a. Revise the cul-de-sac pavement radius to 48 feet. b. Revise the parking driveway aisle from 24 feet to 26 feet wide. c. Revise the public street width from 32 feet to 36 feet wide. d. Increase the full access width off Galpin Boulevard to 44 feet and create three lane access. e. Shift Lots 1 and 8 easterly access further toward the west and realign them across from each other. f. Show at least one, 6-foot wide, side walk along the public street and pedestrian curb ramps. g. Show the access off Galpin Boulevard turning curb radius. h. Realign Lot 5, Block 2 access perpendicular to the shared driveway. 1. Show handicap parking spots and ramps. J. Show concrete driveway apron at every lot access per detail #5207. 32. On the grading plan: a. Extend silt fence between the storm pond and Outlot A. Silt fence Type II must be used adjacent to wetlands and storm pond. b. Revise contour lines to match 3:1 maximum slope and tie the proposed contour lines with the existing contours for Lots 4, 5, Block 2, south of Lot 2, Block 1, and northeast of Lot 1, Block 2. c. Show the proposed contour lines for Lot 3, Block 1. d. Show all retaining walls top and bottom elevations. e. Show all emergency overflows (EOF). The EOF must be 1.5' lower than the adjacent lowest floor. f. Revise Lot 3, Block 1 parking slope to 0.7% minimum. g. Add a note to remove any existing structure and access off Galpin Boulevard and Lyman Boulevard. All disturbed areas, as a result of construction, must be seeded and mulched or sodded immediately after grading to minimize erosion. h. Show 75-foot minimum construction rock entrance. 1. No retaining walls structure is allowed within public street and/or public utility easements, revise accordingly. J. Show contour lines for the berm on Outlot B. 33. On the utility plans: a. Show 20-foot proposed drainage and utility easements between Lots 2 and 3, Block 2. b. Show the proposed sanitary and storm sewer stubs inverts. c. Add storm sewer schedule. d. Public storm sewer pipe type must be RCP and 15-inch minimum diameter. e. The last street accessible storm manhole (STMH#2) must be built with a sump. f. On the utility profile show all sewer and pipe crossings. g. Minimum vertical separation must be 18 inches between watermain and sewer. h. Call out watermain fittings Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 210122 1. Add the outlet control structure per detail #3109. 34. Any retaining wall over four feet in height must be designed by a registered Civil Engineer in the state of Minnesota with an approved safety fence on top of it. Also, it will require a building permit from the Building Department. 35. Add the following City of Chanhassen latest Detail Plate Nos. 1001, 1002, 1003,2109, 2110, 2201,2204,2205,3104,5201,5205,5214,5215,5216,5217,5221,5232,5240,5241,5242, 5302 and 5313. 36. Prior to final plat approval, a professional civil engineer registered in the state of Minnesota must sign all plans. 37. Storm pond is required to be designed to National Urban Runoff Program (NURP) standards with maximum 3: 1 slopes and a 10: 1 bench at the NWL. Submit drainage calculations for staff review. 38. Cross-access easements for the shared driveway accesses must be obtained and recorded against the lots for each of the entrance drives. 39. Any off-site grading will require easements from the appropriate property owner. 40. Public utility improvements will be required to be constructed in accordance with the City's latest edition of Standard Specifications and Detail Plates. Detailed construction plans and specifications will be required at the time of final platting. The applicant will also be required to enter into a development contract with the City and supply the necessary financial security in the form of a letter of credit or cash escrow to guarantee installation of the improvements and the conditions of final plat approval. The applicant must be aware that all public utility improvements will require a preconstruction meeting before building permit issuance. Permits from the appropriate regulatory agencies must be obtained, including but not limited to the MPCA, Department of Health, Watershed District, Carver County, MnDOT, etc. 41. If importing or exporting material for development of the site is necessary, the applicant will be required to supply the City with detailed haul routes and traffic control plans. The applicant should be aware that any off-site grading will require an easement from the appropriate property owner. 42. All private streets are required to have 26-foot wide paved streets from back-of-curb to back- of-curb, be built to a 9-ton design and contained within a 40-foot wide private easement. At the completion of the project, the developer will be required to submit inspection/soil reports certifying that the private streets were built to a 9-ton design. Mr. Todd Gerhardt September 29, 2005 Chanhassen West Business Park Planning Case No. 05-23 Page 22 of 22 43. All of the proposed building pads must have a rear yard elevation at least three feet above the HWL of the adjacent ponds. 44. Installation of the private utilities for the site will require permits and inspections through the City's Building Department. 45. Comply with Carver County memo dated June 28, 2005 and revise the plans accordingly. 46. Revise plan sheet size to 24 x 36 using scale 50. 47. The developer shall dedicate a permanent conservation easement over Outlot C. 48. The applicant shall work with staff to resolve any drainage issues along Lots 5, 6 and Outlot C. 49. The developer shall construct a berm within the 16 foot setback outside the wetland buffer zone on LotS. 50. Revise the construction plans to correspond with the final plat lot designations. 51. Approval of the final plat is contingent upon approval of final construction plans/specifications for the project along with the developer entering into a development contract with the City and supplying the necessary financial security and fees. 52. The developer shall pay the $121,960.80 Arterial Collector Fee. 53. The developer shall work with the City of Chaska to accommodate storm water from properties to the west of the project site." ATTACHMENTS 1. Final plat. 2. Memo to Pat Minger from Paul Moline, Carver County Water Management Dated 9/19/05. g:\plan\2005 planning cases\05-23 Chanhassen West Busines Park\Chanhassen West Business Park fp.doc 6 z ~ Ii: S "- 6 z U o " '" u I- ~~ ;=1:1: ~ Z : ,+. UJC/) \:, C/)C/) C/)UJ c(z ::E:- zC/) c(::) ::E:m o en 8 enW offi~ ili '" >, . ~~~ i5 ~ h ~i -+ "0 ~::5..J '" .... h ~~ zo..< ~ . J" a. I - O*!z i '" ,~ .f " ~ €-j rm (/) en W ili i ~ ilo " I Qo:::::E . ... ~~ " i I cc oz .~ ! .! I ."5 .. ..~ I Q;;J' " J ::i >- 0 ~ ! ." 1 -.J ~~ .. ~ .i. I~ ~~ --+ ~ ..:I. ~~:~ . .! ~ 11~15 <" ;I: VI.>;:: 011 ~i:5 i J ! ~:l ,. ~~ " I 'Ii 0 Ti .5~l:o en l~;j -; !~ I ]ft~ ..1** t ~ l ~~ii "'1- I" 5 ~ irl en <!> S 1 l~i .." ~f; I ~i]~ ~ '," "" o~ of5~ , ! .~] 1'(: ~ ~l 'L-j r.~ii ] ."z :I: W en ~ ~~.~ ., o~t!! , III (/) z..J . 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LO' L&t~ --M.E~.6U)ON-- tJ[JIJ.IJ:a':' J:~S ;~C1':'d C1[]({~':' -]':'Nl:l ;~C1':'d ~m{~':' tmUlaJ:':' CalVer County Water Management- Deparbnent of Planning &Zoning Gavemment CenIEr - Administration Building 600 East 4th Street Chaska, Minnesota 55318 Phone: (952)361-1820 Fax: (952)361-1828 www.co.carver.mn.uslwater Memo To: Pat Minger From: Paul Moline, Carver County Water Management Date: 9/19/2005 Re: Chanhassen West Business park County Water Project WP20050038 cc. Lori Haak, City of Chanhassen Jerry Backman, Schoell-Madson Aaron Mlynek, Carver SWCD Robert Generous, City of Chanhassen Enclosures: SWPPP Comments Carver County Water Management has received plans (dated 8/25/05), SWPPP and hydrologic calculations (dated 8/26/05) for the Chanhassen West Business Park project in the City of Chanhassen. The following comments include review by the County, the SWCD and Wenck Associates: Stormwater Issues: 1. The calculations for existing conditions should be resubmitted and show the effects of ponding in the northeast wetland. The submitted calculations use sheet flow runoff from 35.74 acres to the southwest wetland, which is not representative of the Existing Drainage figure. The increase in runoff may have impacts on downstream and water quality treatment on site. 2. Water Quality calculations need to be submitted for review. 3. Proposed CNs for greenspace should be raised to C type soils to account for the affect of compaction. 4. Downstream capacity of the southwest wetland (Outlot A) should be submitted. 5. The outlet of the northwest wetland (Outlot B) should be submitted. 6. Rainwater Gardens/Infiltration - Additional details are needed including: . Documentation should be submitted for the volume provided for infiltration. Several basins are noted on the plans, but no calculations are provided. . Soils used (sand fill or rock fill, 50% clean sand, 25% loamy topsoil, 25% compost) . Cross-sections . Erosion control blanket and type . Timing of installation (after contributing area is stabilized). . To reduce initial degradation of basins, It is recommended plugs, shrubs and grasses are used in addition to the 'rainwater garden seed mix'. Erosion and Sediment Control: (please contact Aaron Mlynek at the Carver SWCD at 952.442.5101 for questions or assistance on this section) Erosion Control 1. Stable EOF's are needed for the proposed pond on site. The EOF should be clearly labeled on the plan and a detail is needed. The EOF can be stabilized with a turf re-enforcement mat or fabric and riprap. 2. Erosion control blanket should be specified in the swale from the FES to the wetland along the west boundary of the site. The blanket specified should adequately protect the area from designed velocity and depth of flow. The blanket and seed in the swale should be installed within 24 hours of culvert installation. All blanket on the plan should be shown as a shaded area. 3. Erosion control blanket is recommended for the pond slopes from around 952 to 942 contours. All blanket on the plan should be shown as a shaded area. 4. Erosion note number 5 should include 2 tons of mulch per acre with seed for stabilization; seed alone is not considered stabilization. 5. All curb cuts need riprap and fabric or sod installed within 24 hours of curb installation. Sediment Control 1. Temporary sediment basins are needed prior to disturbing upslope areas. The areas of temporary sediment basins should be labeled on the plan. A temporary outlet is needed for the pond; details should be provided. A temporary outlet could consist of a perforated riser and rock cone. Temporary basins are needed in the area of the proposed permanent stormwater pond; the SE corner of the site prior to discharging to the culvert under Galpin. 2. The Wimco inlet control detail proposed will work for all curbside inlets. Any and all area inlets or drop inlets in paved areas will need alternate controls / Wimco details. The engineer should check on alternate designs for Wimco-type inlet controls to fit the various type of inlets. 3. Additional inlet controls may be needed for adjacent inlets on Galpin and Street A. 4. Silt fence will be needed around Outlot A along the east side between the pond the wetland. 5. Silt fence needed for Lot 5, Outlot B. 6. Silt fence needed north of berm in Lot 6 as there is a FES taking water north off site. 7. Silt fence needed south of Lot 1. 8. Each building site will need perimeter controls once the streets are paved and. rock exits will be needed as each lot is built-out. 9. Type 1 and Type 2 silt fence locations need to be specified on the plan. Type 2 should be installed around all wetland areas and in the SE corner of the site to protect the culvert under Galpin. The SF should be extended along the South side to close the gap in the SF. SWPPP A SWPPP review has been completed; any items not marked with an 'x' or 'n/a' need attention. If you have any questions, please feel free to contact me. A follow up meeting may be of benefit. Paul Moline 952.361.1825 pmoline@co.carver.mn.us . Page 2 Cff 4Ai Dcftf1;JcS J jl4fl' /<..- # J;;(s- 1IIIIl Stonnwater Pollution Prevention Plan Checklist ?<' SWPPP contains a combination of )sf' narrative :i{ plan sheets K standard detail sheets (where appropriate) Does the SWPPP Narrative: )f ))escribe the nature of the construction activity? ~ Address the potential for a discharge of sediment and/or other potential pollutants from the site? E:' Identify the person who will oversee the SWPPP implementation? o Identify the entity responsible for long term O&M of the permanent storm water management system? Jijt'" List the chain of responsibility for SWPPP implementation for all operators on the site? ):3::' Describe of installation timing for all Ese BMPs? )a/ Describe procedures to establish additional temporary Ese BMPs as necessary for site conditions? E::' Describe final stabilization methods for all exposed areas? (may be in narrative or on plan sheets) 'i!( Identify storm water management measures needed to mitigate impacts identified as a result of environmental, historical, archaeological, or rare species reviews conducted for the project? ~I !J-r.dentify additional measures being taken to protect Drinking Water Supply Management Areas? JJJ4; If site discharges to impaired reach, identify any site areas discharging to the itnpaired reach? Do plan sheets identify: )(' Existing and final grades? . 6fJ,J 5 ? o Locations and types of all temporary and permanent Ese BMPs? S~3)1.M-~Nr /, I . Ji( Stonnwater flow directions and surface water divides for all pre- and post-construction drainage areas? ,k( Impervious areas? 0' Soil types? ~ Locations of areas not to be disturbed? Q-" Limits of construction phases? ~ Locations of all wetlands and surface waters that will receive pre- or post-construction site runoff (if don't fit on the plan sheets, an arrow to note the direction and distance)? Standard plates or specifications: ~ Are standard plates or specifications included where appropriate? Pa~ IY - Stormwater Discharge Design Requirements ){ Are Temporary Sediment Basins required on site? (10 acres draining to common location) If Yes, are they: o Adequately sized - 2yr, 24hr stonn, min. 1,800 fil /acre; OR no calc. min. 3,600:rr /acre? o Designed to prevent short circuiting? o Are outlets designed to remove floating debris? o Are outlets designed to allow complete drawdown? o Do outlets have energy dissipation? o Have a stabilized emergency spillway? 61/ Permanent Stormwater Management System I(" Is calculation of new impervious surface included in SWPPP? ~ Are calculations for permanent stonnwater management system included (water quality volume of\4 inch of runof!)? 'fO Are there areas of the project where typical treatment methods are not feasible? (up to 1 % of project size or 3 cumulative acres OR proximity to bedrock OR road projects lacking of right of way) ~ If yes, has effort been made to provide some treatment using alternatives? IrGrassed swales tJ Smaller ponds o Grit chambers ~ l1li p! Inspections performed once every 7 days )( Inspections performed within 24 hrs of a rain event greater than 0.5 inl24 hr }i Inspection and Maintenance records include r ~ Date and time of inspection 'tzt Name ofperson(s) conducting inspections ~ Finding of inspections and recommendations for corrective actions A ~ Date and amount of rainfall events greater than 0.5 inl24 hr Main~ance performed - 'Jii. Silt fence repaired/replaced/supplemented when nonfunctional, or 1f3 full; within 24 hours 5-- Sediment basins drained and sediment removed when reaches Vz storage volume; within 72 hours 73; Sediment removed from surface waters within 7 days l}f- Construction site exits inspected, tracked sediment removed within 24 hours \i Addresses pollution prevention management measures: F ~ Solid waste disposed properly; comply with MPCA requirements 1- Hazardous waste stored (secondary containment, restricted access) and disposed in compliance with MPCA requirements 9f External washing of 'Vehicles limited. Runoff contained and waste properly disposed ~ No engine degreasing allowed on site V. Addresses final stabilization: f ?{ Stabilization by uniform perennial vegetative cover (70% density) )'il Drainage ditches stabilized ~ All temporary synthetic and structural BMPs removed ~ Clean out sediment from conveyances and sedimentation basins (return to design capacity) ~ If residential- distribute homeowner factsheet 1 Submit NOT Requirements of Appendix A tJ1 A-IJoes this site drain to a discharge point on the project that is within 2000 feet of a Special Water? Which Tytle of SlJecial Water? BMP CategorY Wilderness Areas C.I, C.2, Co3, C.4 Mississippi River C.I, C.2, Co3 Scenic or Recreational river Col, C.2, Co3 Lake Superior Col, C.2, C.3 Lake Trout Lakes C.I, C.2, C.3, C.4 Trout Lakes C.I, C.2, Co3, CA Scientific & Natural areas C.I, C.2, C.3, CA Trout Streams C.I, C.2, C.3, C.5 Are BMPs required for that Special Water shown on plans? BMP Category C.1 C.2 Co3 C.4 C.5 Requirement protect slopes/provide temp basin for 5 acres draining to common location treat water quality volume of I inch of runoff maintain buffer zone of 100 linear feet from Special Water post project volume/rate control temperature controls ~ DoevPis site discharge to wetlands? r- Has wetland mitigative sequence been followed? .. ~ch method of permanent stormwater treatment has been selected? <J Wet sedimentation basin 'JSI Permanent volume of 1800 tt3 below outlet pipe for each acre draining ~ Minimum depth of 3 ft; maximum depth of lOft lst' Configured so scour or resuspension is minimized 'E( Water quality volume is Y:z inch of runoff from new impervious surfaces l</' Basin outlets designed to discharge at less than 5.66 cfs per acre of pond ~ / Basin outlets designed to prevent short circuiting j)( Basin outlets designed to prevent discharge of floatables [J Stabilized emergency overflow 'll( Is adequate maintenance access provided? ~ ~ Infiltration/filtration l' Is infiltration/filtration appropriate to the site and land uses? Is infiltration system not excavated to final grade until drainage area constructed and stabilized? Are rigorous sediment and erosion controls used to keep sediment and runoff away? Is a pretreatment device used? Is the system sufficient to infiltrate or filter the appropriate water quality volume? Can water qUality volume be discharged in 48 hours or less? o If not, are they routed through stabilized discharge point? Is there a way to visually verify the system is operating as designed? Has appropriate testing been conducted to ensure a minimum of 3 feet of separation? Are calculations and computer model results included to demonstrate the design adequacy of the filtration system? . Is adequate maintenance access provided? Jt ReglOna?;~~~~e maintenance plan identify who will perform future maintenance? r .~ Is written authorization from owner of regional pond included in SWPPP? Is there no significant degradation of waterways between project and regional pond? ~~~ Combin~oo~ ~~~~a:~~~nd design conform to the permit requirements for wet sedimentation basin? ~ . ~ Is the entire water quality volume be accounted for? ~ ~ Are computer models and/or calculations included in the SWPPP? Alternative method . \;J SWPPP, including the Alternative Method documentatio. n, to MPCA for review and approval at l~st 90 days prior to the proposed starting date of construction activity. pa~v - Construction Activity Requirements Addresses erosion prevention measures: )s(/ Are areas not to be disturbed delineated on plans? sl( Has appropriate construction phasing been implemented? ~ Do exposed soils with positive slope within 200 feet of surface water have erosion protection/cover? o Are wetted perimeters of ditches stabilized within 200 feet of surface water? 'f Do pipe outlets have energy dissipation within 24 hours of connecting? ~ Ado/ysses sediment control measures: ~ Are slopes with a 3: 1 grade broken up into lengths less than 75 feet? o Are sediment control practices established on down gradient perimeters? ~ Are all inlets protected? o Do stockpiles have sediment control and placed in areas away from surface waters? Y Do construction site entrances minimize street tracking? " Addresses dewatering and basin draining: r f Is there a plan in place for dewatering so as to not cause nuisance conditions, erosion, or inundation if Addresses inspections and maintenance: 1 Identifies the person who will oversee the BMP inspection and maintenance?