Loading...
HomeMy WebLinkAboutWPO201300074 Checklist 2013-12-04 1.10" ' Albemarle County Engineering Final Plan Checklist Page 1 of 12 WPO2013 ALBEMARLE COUNTY COMMUNITY DEVELOPMENT ENGINEERING REVIEW FINAL PLANS CHECKLIST 11 Apr 2008 (Use the latest checklist at the time of submittal from www.albemarle.org) Application information: (applicable to any type of plan) ., Completed applications and fees (SDP, WPO, etc) [18-32.4.3.2, 18-32.3.9, 17-203, 17- 303] copies of federal and state permits (Army Corps, VDEQ, etc) [Policy] A completed copy of the standard stormwater maintenance agreement and fee for recordation for any stormwater management facilities [17-304E] copies of manufacturer's approval of the plan for any manufactured stormwater management facilities (filterra, stormfilter, sandfilter, etc.) [Policy] pro-rated share payment for any sites which drain to County regional stormwater management facilities. (This should have been identified with the preliminary plan/plat) [17-316] Verify in CountyView if the parcel is subject to rezoning or special use plan proffers. If so, print the proffers and verify applicable conditions have been met. Title information: (applicable to any type of plan) project title [18-32.6.6] professional seal, signed and dated for site plans, major amendments, stormwater plans, or road and drainage plans [18-32.6.1] vicinity map [18-32.6.6] Existing conditions information: (applicable to any type of plan) accurate current existing topography at the time of submittal, including all existing site features, and any recent disturbances, all at a legible scale [18-32.6.6, 14-302] date and source of the topographic information: All topography should be at least visually field verified by the designer within the last year [18-32.6.6, 14-302, Policy for date] benchmark location, elevation and datum for topography. An existing utility or other known position will suffice. [Policy] WPO buffer limits; 100' from stream or wetland bank, 200' from reservoirs,or floodplain limit if greater [17-317] floodplain limits, including 100yr flood limits for any channel with a drainage area of 50+ acres [18-32.6.6d, 14-302] FEMA map and date references labeled for FEMA floodplain [Policy] all existing easements (access, drainage, sight, sanitary easements, etc.) with deed book references, locations and dimensions [18-32.6.6, 14-302] verify there are no proposed buildings in conflict with any existing utilities or easements all slopes 25% and over(critical slopes by County Zoning Ord.) are shaded [18-32.6.6, 14-302] all parcel numbers and owner names for existing property shown *41s0 Albemarle County Engineering Final Plan Checklist Page 2 of 12 Proposed plan view information: (applicable to final site plans, road and drainage plans) Grading: [18-32.6.6, 14-303] proposed topography at minimum 2' contour intervals—tied into existing contours, as well as all proposed site features. (Sites with less than 6' of grade change should consider using smaller contour intervals.) proposed slopes are all 2:1 (horizontal:vertical) or flatter [Policy] proposed slopes steeper than 3:1 have low maintenance(not grass) ground cover specified on the plan [Policy] existing critical (25%) slopes are not disturbed, unless a waiver has been granted by the Planning Commission for the disturbance. [18-4.2, 14-304] retaining walls labeled with maximum height(walls require building permits according to Building Official policy) safety railing shown for retaining walls over 4' high(building permit may be more strict) [Policy] guardrail with VDOT designations shown for retaining walls next to parking or travelways [18-32.7.2] Easements: [18-32.7.4, Subdivision Ordinance, Article IV, Division 4] all proposed permanent easements, dimensioned and labeled Examples of easements are: sidewalk easements for sidewalks to be maintained with streets private sanitary sewer easements for private lines crossing lots public sanitary sewer easements per ACSA drainage easements for any drainage passing through the site from off-site, or for drainage crossing proposed property lines. stormwater management easements over all facilities and associated structures and access access easements intersection or entrance sight easements grading or temporary construction easements all drainage easements are a minimum 20' wide. Required width: 10'+(pipe dia. or channel width)+2'+2(depth-5'). The pipe, channel or structure must be within the center third of the easement. Easement for a yard drain line with minimal (< 3') cover could be reduced to as little as 10' wide if it doesn't impact foundations. [Policy to allow for adequate easement width for excavation] no structures or trees within drainage easements [Policy to allow for excavation] Entrances and right-of-way improvements: [per VDOT Subdivision Street Requirements] all entrances with a VDOT designation(PE-1, CG-9a, etc) entrances do not exceed 4%grade for a distance of 40' from the intersected street, measured anywhere in the entrance [18-4.12.17] unobstructed sight distance lines at entrances, less than (10x speed limit of major road plus 5+speed limit of major road (i.e. 335' for intersection of a 30 mph road))measured from a point 14.5' off the edge of pavement of the intersected street per VDOT Road Design Manual Table 2-7 on page F-35 12.5' minimum radii on entrances (or per VDOT requirements, typically 25'-35') VDOT approval is obtained for any plan affecting public right-of-way turn and taper lanes with lengths and widths labeled (taper at 12:1 with 12' lane widths) Parking and circulation: [18-4.12] New' Albemarle County Engineering Final Plan Checklist Page 3 of 12 100' on-site sight distance is maintained by use of curbed islands a minimum 6' off building corners or other site obstructions. curbing on all parking areas and travelways with VDOT designations (CG-2, CG-6) loading and dumpster areas accessible at all times (not behind parking) all parking rows protected by curbed islands [Policy per 18-.4.12] minimum 3' width of curbed islands [Policy] all edges of pavement labeled(where there is no curbing) parking areas do not exceed 5% grade anywhere, in any direction [18-4.12.15.c] parking width x depth x aisle width is 9x18x24' or 10x18x20' (where a 2' grass overhang is possible parking spaces can be 16' deep per detail 2) parallel parking spaces are 9'x20' (with a minimum aisle width of 20') loading spaces are 12'x25' (with a minimum aisle width of 24') travelways without parking are 20' wide measured from curb faces parking places are separated from entrances and streets (to prevent queuing onto streets) a minimum 18' from back of the entrance radius [sep dist by county engineer : :;] sidewalk abutting parking is 6' wide (exclusive of curb), or bumper blocks are provided (see reference details) sidewalks are a minimum 5' wide, exclusive of curb one-way aisles have a 12' minimum width. (One-way circulation is only permitted when approved with a preliminary site plan) dumpster pads are 10'x10' with 8' in front for wheel bearing(total 18' depth) Drainage: [18-32.6.6d, 14-305, 311] all proposed and existing storm sewer(with arrows indicating direction of flow where it is not otherwise evident) no radial pipes proposed—all have straight alignments principle access free of flooding during the 100yr storm site runoff and entrances do not drain into streets concentrated runoff(lcfs or greater) does not run across travelways [policy] drainage does not run across, through, or backwater in dumpster areas [18-4.12.19] overland relief is provided for any drainage structure or inlet in case of clogging. The failure of any system will not cause structures or yards to flood. [Policy, info per 14-311, 1.8-32.6.6s] direction of flow change (or deflection angle) in each drainage structure is 90 degrees or greater(flow should not have to reverse direction) labels on all drainage structures provided (and should match the drainage computations and profiles) provisions and easements for drainage across 3 or more lots. Dense development where fencing, decking, etc is expected should provide yard inlets and pipes rather than ditches yard drains include raised grates unless in VDOT Right of Way minimum diameter 15"if pipe travels under road or parking area; 12" for yard drains; no minimum diameter for attached roof drains or underdrains Streets: [18-32.6.6, 14-304, Subdivision Ordinance Article IV Division 2, VDOT Subdivision Street Requirements] road plans meet preliminary plat approval and critical slopes waiver approval (if applicable) conditions all existing streets with labeled pavement and right-of-way widths, route numbers and street names all proposed streets, with right-of-way and street names *se Albemarle County Engineering Final Plan Checklist Page 4 of 12 stationing at 50' minimum on all proposed streets,matching the street profile street horizontal curve start point, end points and radii labeled, meeting standards (see the reference details) turnarounds provided on all streets or alleys (see the reference details) street edge of pavement or curb radii labeled at all intersections and turnarounds (see reference details) roundabouts designed per VDOT and ASHTO guidelines (see reference details) guardrail over any slope steeper than 2:1, wall, or drop-off greater than 4', with start and end sections labeled, and VDOT designations (GR-2, GR-2a, etc.) pavement markings dimensioned and labeled signs for traffic control shown and labeled: speed limit on all streets, stop signs at all intersections street name signs at every intersection [County Road Naming and Property Numbering Ordinance and Manual] street tree locations, species and height or caliper send proposed road names to E911 review coordinator and add a review box in CountyView Plan detail information: traffic generation and distribution summary(ADT's) pavement designs typical sections for proposed channels with locations referenced from the plan view sheets sidewalk detail or specification to be a minimum 4" stone base and 4" concrete of 3000psi at 28 days, or stronger. [specs are policy per 14-422] dumpster pad detail or specification to be a minimum 4" stone base and 6" concrete of 3000psi at 28 days, or stronger, reinforced with a minimum grid of wire reinforcing or#4 bars at 12" on center. [specs are policy] typical retaining wall details referenced from plan. A typical manufactures drawing for segmental block walls, or VDOT reference, is acceptable, with any applicable safety railings or guardrail shown. details for any pipes or drainage structures through or under walls, showing endwalls, casings, or structural measures to bridge pipes or structures Albemarle County general construction notes [policy] Street profiles: (applicable only to road or street plans) stationing at 50' minimum on all proposed streets, to match the plan view sheets proposed centerline existing ground centerline labeled existing and proposed grade at each 50ft station point vertical curves provided at all grade transitions vertical curve start, vertex and end points labeled vertical curve length and K labeled at each vertex, meeting required design values (see reference details) percent grades labeled for all road segments,meeting design values (see reference details) Nimre ".w` Albemarle County Engineering Final Plan Checklist Page 5 of 12 rural street intersections continue the-2% intersected cross grade for a minimum of 20' from the edge of pavement of the intersected street. A low point is provided off the intersected street. [policy, following VDOT practice] street grade is less than 4% for a minimum of 40' from the edge of pavement of the intersected street. (This grade can be within the first road curve which transitions from the 2% intersected cross grade) [policy, follows ord. for travelways 18-4.12] pipe and utility crossings shown and labeled cross drain locations shown and labeled with VDOT designations (CD-1,2) at every major cut and fill transition or sag curve the station of intersections are shown and labeled with the street names grades are a maximum of 6%in turnarounds grades are a maximum of 4%through roundabouts Street details containing: (applicable to road or street plans) typical sections for each street, street segment, or alley pavement widths meeting design standards pavement crown at 1/4":1' slope pavement surface,base, and sub-base thicknesses and materials curb and gutter where applicable with VDOT designation(CG-6), and stone base of 6" 21-A or better(CG-2 also acceptable if a gutter is not needed for drainage) shoulder at 1":1' slope or flatter and 4' or greater width for rural sections maximum slopes of 2:1 or flatter [policy] proposed slopes steeper than 3:1 have low maintenance (not grass) ground cover specified on the plan [Policy] guardrail over all fill slopes and culverts, with 3' additional shoulder,using VDOT designations (GR-2, GR-2A, etc.) right-of-way/easement width, centered on street, meeting design standards sidewalk location and widths, minimum 5' width, 4" concrete surface, 4"21-A stone base, with underdrains (UD-4, etc) per VDOT standards where applicable planting strip if applicable, 6' minimum width [14-422] ditches dimensioned at 3:1 slope from shoulder, 1' depth min., and 4' min. width from shoulder to ditch centerline, for rural sections alleys have 12' pavement width, with 14' wide stone base [14-410] transitioning detail (20' minimum) for roll-top curbing in front of any inlets Albemarle County general construction notes for streets Drainage profiles: (applicable to site plans, road and drainage plans) [14-311, 18-32] drainage profiles for each pipe, structure or channel must contain: existing ground proposed ground any channel linings all utility crossings a VDOT designation (MH-1, DI-3B, etc.) for each structure throat length for each drop inlet grate type for each grate inlet a label on each structure to correspond with the computations 'fir` '_Mr Albemarle County Engineering Final Plan Checklist Page 6 of 12 material and strength class or gage of each pipe manhole access every 300' for 15"-42" or 800' for 48" or greater pipe slopes at 0.5%min. to 16%max. (per VDOT stnds for anchors over 16%) concrete inlet shaping(IS-1) specified on any structure with a 4' or greater drop safety slabs (SL-1) in any structure taller than 12'. top or rim elevation for each structure all invert elevations for each structure (with positive flow drop between inverts). end sections (ES-1) or endwalls (EW-1) on all pipe outlets. Endwalls for culverts 48"or taller scour outlet protection at all outlets, corresponding to computations Drainage computations: (applicable to any plan proposing pipes, channels, etc.) Pipe computations for all pipes All proposed systems are designed within open channel full flow capacities. For systems within drainage easements, all proposed pipes are a minimum 15"in diameter There are no excessive outlet velocities (> 15fps) County Engineer approval has been obtained for existing systems which may exceed open channel flow capacity Curb inlet computations for any curb inlets on grade All spreads are less than 10' carryover is accounted for 100% capture at entrances so no flow runs out entrances into travel lanes 100% capture or overland flow of capacity storm to stormwater management facilities Curb inlet computations for any curb inlets in sump conditions All flow depths are below 6"in the capacity table All spreads are less than 10' 100% capture or overland flow of capacity storm to stormwater management facilities Ditch computations for any ditches ditch linings specified per plans meet velocity requirements Culvert computations for any culverts headwaters< 1.5 x culvert height, and 18"below shoulder elevation of streets. Outlet protection computations for all outlets dimensions and stone sizes for all outfalls Proposed pipe and inlet drainage area map limits of all areas and sub-areas draining to proposed structures, and existing structures or channels which will be impacted acreage of each drainage area as used in computations hydrologic coefficient for each drainage area as used in the computations time of concentration for each drainage area as used in the computations destination structure labeled for each drainage area Stormwater management plan: (applicable to any plan containing stormwater management facilities) [17-303,304, and the Virginia Stormwater Management Handbook] *Awe Niupor Albemarle County Engineering Final Plan Checklist Page 7 of 12 Existing drainage area map: existing conditions for site and off-site areas draining to proposed stormwater facilities (The stormwater management analysis should not include off-site areas which do not drain to proposed facilities) drainage divides for all drainage areas to proposed facilities as used in computations acreage of each drainage area, labeled on the map area and matching comps coefficient used for each drainage area as used in comps time of concentration for each drainage area where applicable as used in comps Proposed drainage area map: proposed conditions for the site and any off-site areas draining to proposed stormwater facilities (The analysis should not include off-site areas which do not drain to proposed facilities) drainage divides for total drainage areas (not sub-areas) to proposed facilities,matching the computations. Sub-areas may be shown on added exhibits or sheets. acreage of each drainage area, labeled on the map matching comps coefficient for each drainage area, labeled on the map matching comps time of concentration for each area labeled on the map where applicable, matching comps for future development to be considered in the analysis, include assumed land uses, impervious areas, and hydrologic coefficients on the proposed drainage map Plan view and details: stormwater facility and site layout as shown on the site or subdivision plan sheets, preferably at a scale of 1"=30' or 1"=20'. 90% or more of site development captured in facilities for water quality(ordinance 17- 312.0 requires as much as practical, 90% is a target) Albemarle County general stormwater notes facilities are not in the floodplain facilities are not in buffer areas facilities meet or exceed requirement removal rates facilities are off-line of major streams facilities are not built over any other utilities (sanitary sewer,water, gas, fiber optic, etc.) permanent stormwater management easement encompasses 100yr high water mark, all structures (embankments if present) and access permanent stormwater management easement must be recorded prior to WPO plan approval (easement recordation is not a bond release punchlist item and is not otherwise verified) flow is not short-circuited, flow path is 2:1 or greater in all water quality facilities, without the use of baffles or extended dikes Cross-section details of each facility including; embankments (between 3 and 25 ft in height) top width 8ft min., 10' for heights 15' to 20', 12' for dams over 20', heights measured from the outside toe upstream face slope 2:1 or flatter, labeled downstream slope 3:1 or flatter, labeled 10yr and 100yr high water elevations labeled with 1 ft freeboard for 100yr storm with emergency spillway or 2 ft freeboard without emergency spillway an impervious core a cutoff trench of minimum 4' wide, 4' deep and 1:1 sloped sides principle spillway NNW Albemarle County Engineering Final Plan Checklist Page 8 of 12 riser crest 1' below emergency spillway if present riser crest stays within weir flow control during the 10yr storm trash racks over all inlets and controls to prevent clogging trash rack over riser crest is not flat (no DI-7's) riser size and materials labeled barrel size, strength,material, inverts and slope labeled all orifices, weirs or other control devices labeled with dimensions and inverts control orifices not more than 25% of riser perimeter at any point (does not affect riser structural integrity, 25%is a target) riser base size and dimensions labeled access to riser is provided(riser should be in dam, not free-standing) emergency spillway dimensioned and labeled invert labeled dimensions in control section dimensions in channel section provided if different than control section linings labeled and shown where applicable spillway over native soils, and/or sufficient armoring provided sediment forebays provided for all retention basins, constructed wetlands, and basin biofilters at all inlets sized to 0.25"of runoff per impervious acre (can be included in WQV) direct vehicle access provided biofilters with minimum floor dimensions labeled does not receive any stream base flows, and; areas of sheet flow into facilities are protected from erosion by appropriate scour protection stone or energy dissipation measure plants are shown and labeled with height or caliper 3 plant species are specified(3 trees if present, 3 shrubs)with sizes biofilter floor is 2.5% of impervious cover for type I, or 4% of impervious cover for type II 2.5' depth of sand/soil media 1'-1.5' stone drain in geotech fabric under media, with 6"perforated PVC pipe to daylight 0.5' ponding depth provided in facility overflow provided biofilter area is flat planting soil media conforms to VSMH p. 3.11-28 cleanouts are provided at the end of the underdrain pipe, and every 50' in subdivisions, facilities are in open space where present. In subdivision with no open space, facilities are out of yards and away from residences. Facilities must not be a nuisance in design or location. [17-304F] overland relief is provided for any facility in case of clogging. The failure of any system will not cause structures or yards to flood [17-304F] Retention basins have appropriate water quality volume; 3WQV for type I, 4WQV for type II. good base flow, or 10 acres or more drain to the pond normal pool elevation is labeled on plans 15% of surface area is a depth of 1.5' or less 15% of surface area is a depth of 1.5' to 2' `lere Albemarle County Engineering Final Plan Checklist Page 9 of 12 70% of surface area is a depth of 2' to 6' (greater depths are counted in WQV) a 10'-15' vegetated strip/safety bench is provided around the perimeter for Type III, a 10-15' wide and 1-1.5' deep aquatic bench is provided typical 10'x10' planting area specified for aquatic bench at least 3 species of aquatic plant used extended detention basin II (enhanced)has marsh zones normal pool elevation is labeled on plans 20%pool areas 1.5'-4' deep 40% shallow marsh 0.5'-1.5' deep, contains 1WQV 40%high marsh 0.5' deep or less as-built data is provided for existing ponds and drainage structures and facilities existing ponds and drainage structures and facilities are brought up to current standards (the rest of this list) vehicle access roads provided to all facilities access graded to 10' width and less than 20% grade minimum 10' wide permanent easement over access gravel surface or better for grades over 10% underground facilities have adequate manhole access at upstream and downstream points. manufactured pre-fabricated water quality facilities have a written approval of the plan from the manufacturer. manufactured underground pre-fabricated water quality facilities have a structural certification if proposed under travel ways minimum pipe sizes into and out of the facility are 15"diameter for maintenance Stormwater management computations: (Applicable to any plan with regulated by the Water Protection Ordinance) water quality removal rate computation summary for each facility detention computation summary for each facility channel computations for erosion and capacity for emergency spillway channels drawdown computations for any extended detention facilities riser floatation computations for risers which are not concrete, or are taller than 10' routing model and results for each detention facility hydrology for each facility used to generate inflow hydrographs including; hydrologic land use coefficients (CN, C), areas and flow times for the modified rational method, the critical durations used for the peak basin volume events for 2yr, 10yr and 100yr storms as closely as possible, the drainage areas represent the site development, and not off-site areas computations are provided for composite coefficients reasonable C values are used(0.25 for woodlands, 0.3 for pasture or pre-dev grass, 0.35 for dev. yards, 0.75 for gravel) times of concentration are representative of watersheds. If the omission of small sheet flow areas yields a higher peak flow, the small sheet flow areas are not used. Sheet flow should not exceed 200'. times of concentration generally decrease with development areas over 50 acres make use of more than one hydrologic method to verify computation of peak flows contour areas and elevations used for storage,matching the plans Nal Albemarle County Engineering Final Plan Checklist Page 10 of 12 a stage-storage (elevation vs. storage volume) table with water quality volume requirements computed for facilities with volume requirements the hydraulic dimensions and coefficients for each weir, orifice, culvert or other control structure used in the routing model,matching plans flow control is maintained by the riser when present, not the outlet barrel pipe detention storage and routings are over and above water quality volumes Mitigation Plan (per the Water Protection Ordinance) existing conditions as shown on existing conditions sheets (can be to a smaller scale) proposed conditions as shown on the site or subdivision plan sheet outlined and/or shaded areas of buffer disturbance, with acreages labeled, matching the disturbances shown on the erosion control plan. outlined and/or shaded areas of mitigation, with acreage labeled for re-plantings,mitigation area is equal to disturbed area for channel restoration, 1' of restored channel for every 100sf of disturbed buffer. stations at every 50' min. with existing and proposed cross-sections provided for restoration planting plan for mitigation areas per Riparian Buffers Guidance Manual by CBLAD or the latest policy available from the County's Natural Resources Manager detail provided for typical spacing(i.e. 20'x20'detail with placement). native plants used with species, size,root condition specified maintenance narrative and schedule on plan,including a completion date. areas restored or replanted for mitigation must be protected in easements or by maintenance agreements. all concentrated discharges treated or extended to adequate channels to preserve buffers. Erosion and Sediment Control Plan: (per the Water Protection Ordinance) [Items taken from Water Protection Ordinace, Article I, and the Virginia Erosion and Sediment Control Handbook,minimum standards and specifications] Narrative: narrative and project title project description existing site conditions description adjacent areas description off-site areas description including any off-site areas for borrow, waste or other disturbance. special use permit for cut greater than 50,000cy in RA zoning soils descriptions County erosion control notes stormwater runoff considerations: this can refer to the stormwater management plan sediment basin design computations summary for each sediment basin sediment trap design computation summary for each sediment trap Erosion and sediment control plan: limits of clearing and grading encompassing all disturbances, entrances, staging and parking areas, areas where sediment laden runoff will cross, or any construction related activities. This must match any landscaping and conservation plans a paved construction entrance (CE) draining to a sediment trap or basin '✓ Nue Albemarle County Engineering Final Plan Checklist Page 11 of 12 dust control symbols (DC) temporary and permanent seeding symbols (TS, PS) existing contours and topography existing drainage divides existing vegetation, with trees to be saved located by drip lines. This must match any landscaping and conservation plans protection provided for all stages of construction no erosion control measures in the way of construction access or grading(Diversion dikes or silt fence are not placed in the middle of the site, or through access or grading. Sediment traps are not under or on top of fill. Construction entrances are not on fill, etc. If the concept for site protection is not adequate in this regard, further review of the plan may not be possible) existing soil boundaries are shown with labels. Areas already disturbed are indicated, with constructed fill depth or cut noted. critical erosion areas are identified; areas of constructed slopes, areas near property lines adjacent off-site disturbances are shown with erosion control facilities a stockpile location a staging and parking area, or other construction related areas diversion dikes are used to direct drainage to traps and basins silt fence is not used across contours in place of diversion dikes. silt fence is limited to areas of sheet flow with 1/4 acre per 100ft of level on-grade silt fence temporary slope drains (TSD) or diversions are provided to prevent discharge over disturbed or fill slopes inlet protection(IP) on all inlets culvert inlet protection(CIP) on all culvert inlets outlet protection(OP) on all outlets all watercourses are protected and encroachments minimized stream crossing(USC,SC) and diversions are provided at all stream crossings. final contours are shown per the site or subdivision plan sheets WPO stream buffers shown and protected undisturbed. Disturbances require WPO Program Authority approval and a mitigation plan. Zoning Ordinance buffers shown and protected undisturbed. Disturbances require Planning Commission approval of a waiver. Floodplain shown and protected undisturbed. Disturbances require a Special Use Permit. final contour shapes and slopes ensure no undrained pockets or stagnant pools adequate channels (MS-19)provided for each outfall all swales and low points at the perimeter of the site have a sediment trap or basin (If the concept for site protection is not adequate in this regard, further review of the plan may not be possible) all traps and basins are shown with proposed contours For each trap; drainage area is 3 acres or less sized for total drainage area, including those for in-line upstream facilities wet storage is 67cy or more dry storage is 67cy or more wet storage is 4' deep or less wet storage side slope is 1:1 or flatter tt Albemarle County Engineering Final Plan Checklist Page 12 of 12 dry storage side slope is 2:1 or flatter stone weir is 6ft per acre of drainage area embankment and stone weir height is 5' maximum from outside toe embankment top width is adequate (see table 16 reference) 2:1 length:width ratio for flow path For each basin; sized for total drainage area, including those for in-line upstream facilities wet storage is 67cy or more dry storage is 67yr or more wet storage side slope is 1:1 or flatter dry storage side slope is 2:1 or flatter embankment 15' high or less from downstream toe principle and emergency spillways sized per handbook requirements embankment has 1' freeboard during 25yr storm with emergency spillway embankment has 2' freeboard during 25yr storm without emergency spillway trash rack/ anti-vortex device specified per handbook requirements riser anchor size specified per floatation computation dewatering device sized for 6+hr drawdown of dry storage: 3"dia. minimum safety fence and signs stating"danger, quick sand, do not enter"provided if near any residential properties, or public access structures and embankment match permanent design for facilities to be converted to permanent stormwater management facilities embankment top width is adequate (see reference details) 2:1 length:width ratio for flow path. If necessary, baffles specified only on temporary structures Details: a paved construction entrance detail (see reference details) for projects in the development areas over 10 acres a typical section for each temporary channel or diversion,referenced from the plan sheets. Existing ground should be shown at the maximum cross-slope on the plan. details and copies of Program Authority permissions for any variances. Misc: mass grading(also called rough or early grading plans which contain only approximate finished grades and culverts necessary to grade.) can only be permitted within planned developments where a concept grading plan was approved with the rezoning. The agent (Director of Planning)needs to formally determine that the grading plan is in general conformity with the approved rezoning plan. Otherwise, all final plans need to be approved prior to issuance of grading permits.