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HomeMy WebLinkAboutSite Certifications - 11/15/2018/15 Page 1 OVERALL SITE and DRAINAGE CERTIFICATION Commercial, Multi-Family and Subdivision Certification Form and Checklist Project Name: Date: Building Permit Numbers: (Commercial or multi-family) Per the requirement in Fort Collins Stormwater Criteria Manual (FCSCM) Volume 1, Section 6.11, please fill in all applicable items in this Certification Form for Commercial, Multi-Family and Overall Single Family sites. NOTE: several items must be verified during construction. A copy of the approved grading plan must be submitted with the as-built grading plan. (As-built elevations must be written in red next to the approved elevations.) x Use “Yes” for items completed as described. x Use “N/A” for items that are not applicable to the site being certified. x If any blanks are “No,” attach an explanation referencing the item number below. Attach an explanation or description of the as-built condition for any items listed or for anything not listed but shown on the approved construction plans. Provide an as-built redline or Mylar drawing with the following: I. Water Quality and Quantity Detention Basin Certification - FCSCM Vol.2, Ch.10 For multiple detention basins on a site, provide the following for each basin separately: A.Volume: As-built topographic verification is attached at 1-foot (or less) contour intervals and volume verification calculations for the water quality capture volume and the 100-year detention storage volume. 1. Detention basin topography was prepared by a professional land surveyor registered in the state of Colorado. 2. Both proposed and as-built contours are shown on the same plan sheet (dashed lines for proposed and solid lines for as-built). 3. All critical spot elevations as shown on the approved construction plans have been verified and the as-built elevations are shown on the plan sheet. 4. Stage-storage-discharge tables are provided on a separate document. 5. Verification that designed drain time is in compliance with Colorado Revised Statute § 37-92- 602(8) is attached and has been uploaded to the Statewide Compliance Portal (tinyurl.com/COCompliancePortal) for approval. Uploaded documents must include: a. The cover sheet from the approved drainage report b. The stamped certification page from the approved drainage report c. As-built topographic survey d. Stamped certification page from the Overall Site & Drainage Certification e. PDF output from the Stormwater Detention and Infiltration Design Data Speadsheet Riverside Storage 9/12/18 B1600182, B1507695, B1507699, B1507653, B1507650, B1507703 Yes Yes Yes Yes Yes Yes Escrowed on 10/25/2016 for site and to release building COs Certification (site and buildings enclosed) accepted and escrow released 11/15/2018 DJM Yes N/A Yes N/A Yes Yes Yes Yes Yes Yes Yes 0.5% Type L 6" Yes 4935.38 4935.30 Yes No Yes Yes Yes Yes No N/A Yes Yes Yes Yes Yes Yes N/A /15 Page 4 III. Storm Pipes (aka storm drains) - FCSCM Vol.1, Ch.6, Sec. 4 A.Storm Drain Pipe Capacity: The as-built capacity of all pipes installed on this project has been verified and meets or exceeds the capacity requirements shown in the approved drainage study for this project. 1. All storm drain pipe sizes and materials have been verified and are in conformance with the approved construction plans. (Indicate on the plan and profile sheets that they have been verified.) Material and size substitutions must be approved prior to installation. If a pipe size or material was changed during construction, the certification engineer must attach the approval documents or supply them with this certification. Approval documents must include a calculation documenting the capacity equivalency (equal or greater) of the substituted size. 2. The longitudinal slope of the pipe is as shown on the approved construction plans. The acceptable minimum slope is 0.4%. All slopes flatter than the designed slope on the construction plans must be justified with capacity calculations on an attached sheet. 3. The as-built invert elevations have been verified and are shown on the plan and profile sheets of the approved construction plans. B.Storm Drain Pipe Installation Requirements: All pipes are installed in accordance with the approved construction plans. 1. The minimum cover requirements for all pipes have been met as shown on the approved construction plans. These will be called out in critical locations. 2. All encasements and clearances as specified on the approved construction plans have been met. 3. Any specific joint types or construction methods specified on the approved construction plans have been met. (List on a separate sheet and attach to this certification.) IV. Concrete Pans - FCSCM Vol.1, Ch.7, Sec.4.1.3.4 A.Construction/Installation: All concrete pans have been constructed in accordance with the approved construction plans. 1. The concrete pans are the correct size/width as shown on the approved construction plans. 2. The longitudinal slopes of the pans are as shown on the approved construction plans. The certification engineer must justify or mitigate longitudinal slopes less than the minimum of 0.4% unless a flatter slope was approved and is shown on the approved construction plans. Provide mitigation or justification by separate document. 3. The cross-section of the pan is as shown on the construction plans. (Specifically, the pan cross- section is “V” shaped and meets the side slope shown on the detail.) 4. The concrete pans are a minimum of 6 inches thick without reinforcement and a minimum of 4 inches thick with a minimum of 6X6-W14xW14 reinforcement per detail D20B and D20C. (Provide documentation of the reinforcement used if different than shown on the details or on the approved construction plans.) 5. The spot elevations shown on the concrete pan(s) have been verified and are shown on the as- built drawings. Yes Yes Yes Yes Yes Yes N/A N/A Yes Yes Yes Yes Yes Yes /15 Page 5 V.Storm Drain Inlets - FCSCM Vol.1, Ch.6, Sec. 3 A.Construction/Installation: All storm drain inlets have been constructed in accordance with the approved construction plans. 1. The size and type of inlets are consistent with the inlets shown on the approved construction plan. Indicate by writing “Verified” on each inlet on the plan sheet or list on a separate document the inlet number(s), type and size (length). If the inlet installed is other than the one on the approved construction plan detail sheet, provide the name and source of the detail with justification for equal or better capacity. 2. The size of the inlet opening is consistent with the approved detail. (Check height and width.) 3. The elevation of the grate (if applicable) is at the elevation shown on the street profile or as indicated by a spot elevation on the construction plans. 4. The as-built invert elevations of all pipes entering and leaving the inlet are shown on the plan and profile sheets within construction tolerance of 0.2 feet. If substantially different, provide justification and capacity calculations to show the capacity is not affected or propose mitigation. 5. The as-built size of the inlet box is as shown on the construction plans or an explanation or justification is attached. 6. All inlet covers are stenciled or stamped with the following designation: NO DUMPING – DRAINS TO POUDRE RIVER. VI. Culverts - FCSCM Vol.2, Ch.9 A.Construction/Installation: All culverts have been constructed and/or installed in accordance with the approved construction plans. 1. All culvert sizes have been verified as indicated on the as-built construction plans as correct. 2. The culvert material type for all culverts installed is as on the approved construction plans and is indicated on the as-built plans. 3. The as-built invert “in and out” elevations have been verified and are indicated on the as-built construction plans. 4. The culvert headwalls or wing walls have been installed as shown on the approved construction plans. Headwalls or wing walls may be needed in the as-built conditions onsite if the slopes adjacent to the culvert are greater than 4:1. Please note areas needing stabilization in the certification narrative. An alternative to consider is a turf reinforcement mat (TRM). VII. Sub-Drains A.Construction/Installation: All sub-drains shown on the construction plans have been installed in accordance with those plans. Sub-drains installed with the sanitary sewer are to be verified on the sanitary sewer plan and profile sheets of the construction plans. (NOTE: Indicate any sub-drains installed after the plans were approved on the as-built plans.) 1. The size of the sub-drains are as approved on the construction plans and are indicated on the as- built plans. 2. The type of sub-drain, in particular the perforated and non-perforated sections of the drain, are as indicated on the approved construction plans. Yes Yes Yes Yes Yes Yes Yes N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Yes Yes Yes Yes Yes Yes Yes Yes /15 Page 7 2. The as-built contours for “overlot grading” are shown on the as-built construction plans for all common open spaces, tracts, outlots, etc. If not in compliance, please attach a narrative describing the situation for noncompliance and when it may be corrected. An escrow for overlot grading may be required. (NOTE: Residential Lot Grading Certification is a separate process from this Overall Site Certification. It is understood that residential lots will be brought to final grade once the foundation is backfilled so they may be lower than the plan shows at this Overall Site Certification stage.) 3. All turf reinforcement mats (TRMs) have been installed as shown on the approved construction plans and the slopes are stabilized. XI. Riprap - FCSCM Vol.1, Ch.7, Sec.4.4.4.3 A.Construction: All riprap has been installed in the locations and sizes indicated on the approved construction plans. XII. Permanent Erosion Control Fabric - FCSCM Vol.1, Ch.7 A.Construction: All fabric has been installed in the locations and sizes indicated on the approved construction plans. 1. All fabric was installed per the details on the approved construction plans. XIII. Post-Construction Site Cleanup - FCSCM Vol.3, Ch.7 A.Construction: All construction debris and obstructions of any kind have been removed from drainage paths. 1. All construction debris has been removed except in staging area(s). 2. All ruts have been smoothed out in all construction areas. 3. All areas needing reseeding have been identified and future stabilization goals have been coordinated with the Erosion Control Inspector and in accordance with FCSCM Vol.2 Chapter 12. Note the area needing stabilization in the narrative. XIV. Certification of Other Permanent BMPs - FCSCM Vol.2, Ch.8, Sec.2 & FCSCM Vol.2, Ch.12 A. The construction of channel drop structures is in accordance with the approved plan both in location, horizontal dimensions and cross-section. XV. Certification of LID and Water Quality Facilities - FCSCM Vol.3, Ch.4 A. Attached are the During Construction Inspection Checklist for Low Impact Development (LID) and other items to be verified during construction, along with pictures and other required documentation. N/A Yes Yes N/A Yes N/A N/A Yes Yes Yes Yes /15 Page 8 XVI. Certification and Erosion Control Measures A.All temporary erosion control measures shall be removed upon stabilization. If at the time of preparing this certification there are any erosion control measures still remaining on the site, please note them in the narrative and verify that they need to remain at this time. If in doubt as to the need for any control measure, please consult with the Erosion Control Inspector at 970-221-6700. XVII. Statement of Compliance A.This certification is signed and stamped. By signing this form, the engineer(s) attests that he/she has visited and observed the site, and to the best of his/her knowledge, the as-built conditions of the drainage facilities are as described in the above form and in the enclosed as-built plans. B. Failure to properly disclose all known information could result in the rejection of this certification and prevent the release of any and all Stormwater Utility permit holds on Building Permits and/or Certificates of Occupancy within this development. XVIII. Signature and Stamp by a Colorado-Registered Professional Engineer Engineer’s contact information: Name: Email: Phone: Company: Address: PE Stamp Sign and date 10/22/18 Patricia Kroetch tricia@northstardesigninc.com 970-481-9873 North Star Design Inc. 700 Automation Drive, Unit I Windsor, CO 80550 /15 Page 1 DURING CONSTRUCTION INSPECTION CHECKLIST To be completed by Construction Superintendent This checklist is to be completed during construction and included with the Overall Site and Drainage Certification. x Use “Yes” for items completed as described. x Use “N/A” for items that are not applicable to the site being certified. x If any blanks are “No,” attach an explanation referencing the item number below. I. Compaction A. All berms and embankments meet the compaction requirements as specified in the project geotechnical report or comply with the City’s standard, which is “soils should be compacted within a moisture content range of 2% below to 2% above optimum moisture content and compacted to 95% of the Maximum Standard Proctor Density (ASTM D698).” Compaction requires verification during construction. Provide testing log from contractor/engineer. II. Storm Drain Pipe Installation Requirements A. The pipe trenches have been compacted in accordance with Section 02225-3.07.A.1. of the Fort Collins Development Construction Standards (e.g., the trenches in the roadways are to be 95% of maximum density and all other areas are to be at 90%, both in accordance with ASTM D698). III.Riprap - FCSCM Vol.1, Ch.7, Sec.4.4.4.3 A. The riprap bedding is a granular bedding of the gradation and thickness indicated on the approved construction plans. B. A filter fabric was installed instead of granular bedding and is the material shown on the approved construction plans or was an approved equal. Provide documentation for an approved equal. C. The riprap is the gradation shown on the approved construction plans with a D50 of . D. The riprap thickness is as shown on the approved construction plans and extends to the horizontal limits shown. E. The riprap is buried to the depth indicated on the approved construction plans. (A minimum of 6 inches of soil is required.) IV.Permanent Erosion Control Fabric - FCSCM Vol.1, Ch.7 A. All fabric was installed per manufacturer’s specifications. V.Certification of Other Permanent BMPs - FCSCM Vol.2, Ch.8, Sec.2 & FCSCM Vol.2, Ch.12 A. All cut-off walls have been installed in accordance with the approved construction plans. (Cut-off walls are required for irrigation ditch crossings of storm drain pipes and at the end of flared end sections.) 6" Yes Yes No No Yes No No N/A N/A Riprap Note: Due to legal ramifications, the riprap was not installed per plan as the horizontal limits of the rip rap were minimized to prevent conflict. Negotiations were completed in good faith without a resolution. The riprap that what was installed is suitable for permanent erosion protection given that runoff from most minor storm events will percolate into the soil rather than flow through outlet structure to follow the historic flow path. /15 Page 2 Permeable Interlocking Concrete Pavers Item/Activity Yes No N/A Documentation/Submittal Requirements Excavation Post-excavation infiltration rates are consistent with design infiltration capacity (for “full or partial infiltration” designs) Impermeable Liner Impermeable liner meets design specifications Impermeable liner attached to concrete perimeter wall Impermeable liner is not exposed Any penetrations of the impermeable liner have been sealed and checked for water-tightness. Concrete Cut-Off Wall Meets specifications for: - Dimensions - Reinforcement - Footings Underdrain System Underdrain pipe is per design specifications At least one cleanout is provided per underdrain lateral Cleanout pipe is not perforated Cleanout covers are installed and watertight Underdrain is NOT wrapped in geotextile fabric Underdrain orifice plate installed at outlet structure Underdrain integrity tested after backfilling using TV and/or water test Aggregate Base coarse (e.g., #2/4) has 90% fractured faces Bedding coarse (e.g., #89) is thoroughly washed Sub-base materials are installed and compacted according to manufacturer’s specifications Protection During Construction PICP area is protected from construction site sediment, including runoff from the upstream catchment and construction equipment traffic Close Out Upstream catchment is stabilized prior to diverting runoff into PICP system ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ /15 Page 3 Bioretention Cells Item/Activity Yes No N/A Documentation/Submittal Requirements Excavation Heavy equipment did not travel over bioretention cell during excavation Bottom of cell was “ripped” after excavation Photograph before/after “ripping” Bottom of cell is flat and level Photograph Excavated area is protected/surrounded by sediment/runoff control BMPs during construction Photograph Inlet Overflow inlet elevation is set above bioretention media per plan (typically 12 inches) Overflow inlet invert elevation is at least 3 inches below containment wall/berm (to direct overflow into inlet) Measure/record distance between inlet and top of containment wall/berm Upstream catchment drains to inlet Forebay Forebay is installed according to design specifications Forebay has flat, concrete bottom Outlet Structure/Overflow Outlet structure/overflow elevation is confirmed Measure/record distance from overflow to top of media filter Impermeable Liner Impermeable liner meets design specifications Impermeable liner attached to concrete perimeter wall Impermeable liner is not exposed Underdrain System Underdrain pipe is per design specifications At least one cleanout is provided per underdrain lateral Cleanout pipe is not perforated Cleanout covers are installed and watertight Underdrain is NOT wrapped in geotextile fabric Underdrain orifice plate installed at outlet structure Underdrain integrity tested after backfilling using TV and/or water test ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ /15 Page 4 Filter Media Filter media composition is per design specifications Filter media was “machine mixed” by supplier prior to delivery Filter media installed flat and level Other Structural Components Containment wall/berm is continuous and level Landscaping Final landscaping does NOT include sod Final landscaping (wood/rock mulch) is flat and level Vegetation is planted according to landscape design specifications Verify that weed barrier is not installed Temporary irrigation installed If N/A, then verify that permanent irrigation is installed to establish/maintain vegetation Close Out Upstream catchment stabilized prior to diverting runoff into bioretention cell Signature: Name: Title: Email: Phone: Company: Address: ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ ✔ Jason Luna Construction Company Owner Jason@BuildWithStrategy.com 970-430-0144 Strategic Property Advancement, LLC PO Box 270730 Fort Collins, CO 80527 STAGE - STORAGE TABLE (100-YEAR) LOCATION: First Replat of Prospect Riverside Subdivision PROJECT NO: 264-10 COMPUTATIONS BY: PPK SUBMITTED BY: North Star Design, Inc. DATE: 7/8/2015 100 yr Detention Volume Required = 0.342 Water Quality Volume Required = 0.076 Total Volume Required= 0.418 DESIGN POND VOLUME Surface Incremental Total Stage Area Storage Storage (ft)(ft2)(ac-ft) (ac-ft) 4934.30 0 4935.0 7,850 0.042 0.04 WQCV 4935.30 9,528 0.060 0.102 4936.0 13,442 0.242 0.284 100 WSEL 4936.36 19,395 0.134 0.418 4937.0 30,070 0.487 0.770 AS CONSTRUCTED POND VOLUME per survey 3/8/18 Surface Incremental Total Stage Area Storage Storage (ft)(ft2)(ac-ft) (ac-ft) 4934.02 0 4935.0 6,956 0.052 0.05 WQCV 4935.27 8,823 0.050 0.102 4936.0 13,769 0.233 0.286 4936.2 16,068 0.068 0.354 100 WSEL 4936.36 18,726 0.134 0.419 4936.4 19,277 0.151 0.437    DURINGCONSTRUCTIONPHOTOS   RAINGARDENINSTALLATION            POSTCONSTRUCTIONPHOTOS Swalealongsouthboundary       Permeablepavements     Westsideofsite    RainGardeninDetentionPond    Swalealongnorthboundary      DetentionPond&Drywell  A Westrian Company 1640 RIVERSIDE Post-Construction Topography Spot Elevations 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176 A Westrian Company 1640 RIVERSIDE 34176