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HomeMy WebLinkAboutResolution No. 513-17 - 2017Subdivision&Non-ResidentialLotGradingPlanChecklist RESOLUTION BE IT RESOLVED by the Common Council of the City of Rochester that the City adopt the 2017 Subdivision and Non-Residential Lot Grading Plan Checklist. A copy of the checklist is attached. PASSED AND ADOPTED BY THE COMMON COUNCIL OF THE CITY OF ROCHESTER, MINNESOTA, THIS __________ DAY OF _______________, 2017. ___________________________________ PRESIDENT OF SAID COMMON COUNCIL ATTEST: __________________________ CITY CLERK APPROVED THIS _____ DAY OF ______________________, 2017. ________________________________ MAYOR OF SAID CITY (Seal of the City of Rochester, Minnesota) Res15\\PW\\Adopt.GradingPlanChecklists.17 SUBDIVISION AND NON-RESIDENTIAL LOT GRADING PLAN CHECKLIST Revised November 2017 Key Site: = Yes Prepared By: Date: = No Blank = Not Applicable Reviewed By: Date: Temporary stockpiles include additional sediment control GENERAL and temporary cover after 14 days (7 days if discharging to Completed grading permit application form. and within 1 mile of impaired water). Final grading plan is signed by a licensed professional. Soil within 1 mile of impaired water stabilized within 7 Submitted signed Drainage Report per City template. days. Provide owner name, mailing address and email address. Percent of slope is shown for streets and drainage swales. Provide SWPPP for projects requiring the MPCAs Fill & cut property line setbacks are >2' for cut slope ht. Construction Stormwater Permit. > 10' or fill slope ht. >4'; setback is dimensioned on the plans. Plan is drawn in two-foot contours. All finished contours All proposed lot corner elevations are shown. and adequate existing contours are labeled. Proposed elevations of garage, lowest floor, ground at front Existing contours are dashed and proposed are solid. and rear of building, along with the structure type. Directional arrows are shown for proposed drainage. Details of terrain and drainage are provided for areas Top of foundation is minimum 6 above the ground. adjacent to the proposed grading. Grade l' below top of foundation 10' from building. Existing public and private utilities are shown. Freeboard to structures. Floor el. or the grade adjacent to the Areas not to be disturbed clearly defined. building is at least l' above any overflow elevation or at least ALL receiving waters, including wetlands, within 1 mile 2' above any pond 100-year water level, whichever is shown or identified, including impaired waters. greater. Minimum l' above FEMA flood elevation. Property limits are shown, streets are labeled, lot & block Drainage flows away from structures at min. 2%. information provided, and street address shown, if known. Temporary or permanent diversion swales, stabilized with County/MnDOT permit obtained for work in their ROW. turf mat, pipe, riprap, are used at the top of slopes exceeding Substantial Land Alteration approved for elevation changes 4:1, when applicable. > Minimum lot slopes for vegetated areas are 2% minimum. All City Council approval conditions are met. Temporary or permanent cover is indicated for all disturbed The following areas are tabulated for residential (acres): areas. Temporary seeding specifies seed mix including disk Total platted area (site area) anchored mulch on all slopes > 200' or > 5% slope. Total area disturbed Permanent cover specifies 4" min. topsoil, seed mix and disk Total developable area (excluding floodway, natural anchored mulch, or 4" min. topsoil and sod. steep slopes, & wetlands). Slopes steeper than 4:1 and 4:1 slopes longer than 30' are The following areas are tabulated for non-residential seeded and protected with erosion control blankets (MnDOT (acres): 3885.1) or sodded and staked. Total project area; total disturbed area Statement that slopes steeper than 4:1 are stable from land- Total impervious areas of project, existing & proposed. sliding and surface erosion. Geotechnical report for slopes Tabulation of total and impervious area by tax parcel. >3:1. Schedule of BMP installation shown. For sites where temporary or permanent cover will not be BMP details included are City standard plates referenced. complete by November 15, plan provides adequate measures Concrete washout management and waste control BMP to control spring erosion and sedimentation. addressed on plan. Dewatering activities discharge to treatment facility. DRAINAGE SWALES & EASEMENTS Per the NPDES Construction Storm Water Permit, the date Drainage and Utility easements are shown and labeled. and amount of all rainfall events greater than ½ inch in 24 hours must be documented. Rainfall amounts must be Drainage easements are provided where concentrated flow is obtained from a properly maintained rain gage installed on received from more than 1 adjacent lot and also where site, a weather station within 1 mile of the site, or a weather concentrated flow is received from more than 1 acre of reporting system that provides site specific rainfall data from adjacent property. 100-year flow contained in easement. radar summaries. Minimum drainage easement for flows from 1 acre or less or 4 lots or less are a minimum of 15' wide. Ditch is SITE GRADING, SEDIMENT & EROSION CONTROL 1.9' deep V -shaped with 4:1 slopes. All erosion and sediment control shall conform to the Minimum drainage easements for flows from more than 1 provisions of the MPCAs Construction Stormwater Permit. acre or more than 4 lots are a minimum of 20' wide. Ditch is Down-slope sediment control scheduled before grading. a minimum of 2' deep with a 4' bottom and 4:1 slopes up to Adjacent property protected from drainage and sediment. the easement line. 100-year runoff contained in easement. Stabilized vehicle exit(s) are provided. Control elevations for drainage ways are provided. Silt fences are provided. Minimum slope of small drainage swales is 2%. All storm sewer inlets, existing and proposed, have inlet protection/ that remains until up-slope areas are stabilized. Maximum unbroken 3:1 or steeper slope of 75 feet. systemand discharge volume is lessthan 110% of the pre- DRAINAGE SWALES & EASEMENTS (continued) Drainage easements for flow from more than 1 acre or 4 lots developed condition. are seeded and protected with erosion control blankets or Pipe outlet energy dissipation complete within 24 hours of sodded. Blanket category specified per MnDOT 388S.1. connection to surface water or outlet. Plan depicts required blanket locations. Evaluation of downstream adequacy provided (capacity & Velocity computations are provided for drainage easements stability). where concentrated flow from more than 2 acres or 8 lots is POST CONSTRUCTION STORMWATER MANAGMENT directed. Where 10-year velocities exceed 5 ft/sec, For construction activity adding one or more acres of permanent turf reinforcement mats are installed per City std. cumulative impervious surface area as a single project or plate 7-07. Mats per MnDOT 3888.1 or manufacturer and common plan of development, all provisions of product is specified. Plan depicts blanket locations and cross Construction Stormwater Permit for Permanent Stormwater sections. Management Systems shall apply, along with the items Easement documents are signed and submitted to Public below. Works with recording fee or included in plat. BMPs shall be implemented with highest preference given to Ditches within 200' of surface water or Property line Green Infrastructure techniques and practices, e.g. stabilized in 24 hours after connection infiltration, evapotranspiration, etc., necessary to meet the following Post Construction Stormwater Management STORM DRAIN SYSTEM, INLETS, & OVERFLOWS conditions on the site of a construction activity disturbing Atlas 14 Intensity-Duration-Frequency (IDF) curve must be one acre or more or smaller projects part of a common plan used when designing storm sewer system using the rational of development to the maximum extent practicable: method. If storm sewer is designed using SCS For new development no net increase from pre-project methodologies, the 10 year design event rainfall depth must conditions for stormwater volume, TSS and TP. be used. For redevelopment a net reduction from pre-project The Neenah curb opening calculator (or approved equal) conditions for stormwater volume, TSS and TP. shall be used to verify that double catch basins are spaced Limitations prohibiting the use of infiltration techniques appropriately to maximize capture efficiency. include: All storm sewer structure invert and rim elevations are Where industrial stormwater permits do not authorize labeled along with pipe size and types. infiltration practices Where vehicle fueling and maintenance occur 400' max. manhole spacing for pipes 15" diameter or less. Where less than 3 feet separation is present between 500' max. manhole spacing for pipes 18" to 30" diameter. bottom of BMP and bedrock and/or saturated soils Drainage from subdrains, sump pumps, and building storm Where high levels of contaminants in soil or groundwater drains does not connect directly to public storm sewer. will be transported Not more than 3 CBs in a series (at an intersection) before Infiltration shall be restricted without higher engineering connecting to the storm sewer main. review and substantiation sufficient to provide a functioning Storm sewer trunk generally does not flow through CBs. treatment system and prevent adverse impacts to groundwater when an infiltration BMP will be constructed in Drainage does not cross intersections (no valley gutters). areas: CB spacing as necessary for inlet capacity and spread width With predominantly HSG D soils that does not exceed 1000' on residential streets or 600' on Within 1,000 feet up-gradient or 100 feet down-gradient collector and arterial streets. of active karst features Storm sewer inlets include trash racks per City standards. Within a DWSMA With exception of single family homes, stormwater runoff Where soil infiltration rates exceed 8.3 inches/hour from impervious surfaces is collected on-site and not sheet Lesser volume control on the site of the original construction drained onto sidewalks, rights of way or adjacent property. activity may be allowed under the following circumstances: Concentrated drainage is collected in CB before crossing Where any of the infiltration related limitations described walk. above are present Emergency overflows are provided that limit depth of The owner and/or operator of the construction activity ponding in the street to 2' or less. implements to the maximum extent practicable, volume Emergency overflow with the high point elevation and reduction techniques, other than infiltration on the site of direction of overflow are clearly marked on plans. the original construction activity that reduces stormwater discharge volume, but may not meet the full Post Emergency overflow meets minimum drainage easement Construction Stormwater Management requirements. standards. For linear projects where lack of ROW precludes the installation of volume control practices that meet the OUTLETS & ENERGY DISSIPATION conditions of Post Construction Stormwater Management, Energy dissipation and scour protection shall be provided at lesser volume control may be allowed so long as a storm sewer and culvert outfalls in accordance with City reasonable attempt be made to obtain ROW during planning. and/or MnDOT standards. Where volume control practices cannot be implemented on Stormwater discharge onto slopes steeper than 10% shall be site of original construction activity, prohibited unless discharge is into existing conveyance All BMPs shall be designed in accordance with City and/or Minnesota Stormwater Manual standards ADDITIONAL NOTES: