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HomeMy WebLinkAboutWPO201800044 Review Comments WPO VSMP 2018-10-10COUNTY OF ALBEMARLE Department of Community Development 401 McIntire Road, Room 227 Charlottesville, Virginia 22902-4596 Phone (434) 296-5832 Fax (434) 972-4126 VSMP Permit Plan Review Project title: Royal Fern Project file number: WP0201800044 Plan preparer: Shimp Engineering [Justin@shimp-engineering.com] Owner or rep.: Gambit LLC & Snow Paws LLC et als P.O. Box 6846, Charlottesville, VA 22906 Plan received date: 7 Jun 2018 (Rev. 1) 4 Sep 2018 Date of comments: 19 Jul 2018 (Rev. 1) 10 Oct 2018 Reviewers: John Anderson County Code section 17-410 and Virginia Code §62.1-44.15:34 requires the VSMP authority to act on any VSMP permit by issuing a project approval or denial. This project is denied for reasons listed, below. The VSMP application content requirements can be found in County Code section 17-401. A. Stormwater Pollution Prevention Plan (SWPPP) The SWPPP content requirements can be found in County Code section 17-405. A SWPPP must contain (1) a PPP, (2) an ESCP, (3) a SWMP, and (4) any TMDL measures necessary. 1. SWPPP anticipated with first revision submittal. (Rev. 1) Asfollow-up: Ensure SWPPP Sec. 1 Registration Statement Area to be Disturbed (12.40 Ac.) and VSMP Plan LOD (C7, ESC Legend, 4.00 Ac.) match. B. Pollution Prevention Plan (PPP) — (Rev. 1) Addressed The PPP content requirements can be found in County Code section l 7-404. 1. Anticipate PPP (Sec. 6, County SWPPP template) and SWPPP Exhibit with first revision submittal. C. Stormwater Management Plan (SWMP) VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is disapproved for reasons outlined, below. The stormwater management plan content requirements can be found in County Code section 17-403. Proposed design, VSMP and Road Plan, must be consistent with approved final site plan for Brookdale, a development with shared property line immediately west, FSP approved 2/7/18 (SDP201700069). Brookdale documents are available on County View. There are two primary, ice: proposed release point for (Royal Fern) proposed biofilter is inconsistent with now -approved Brookdale development, with both approved grading and SWM design. Royal Fern discharge of post -development runoff to Brookdale parcel must be shown to work with approved Brookdale VSMP (WP0201700081). Second, VDOT /Albemarle note that the proposed entrance to Royal Fern on Mountainwood Road overlaps an approved entrance to Brookdale. VDOT and county subdivision and private road standards would not permit this geometry. Please consult with VDOT on possible approvable locations for subdivision entrance on Mountainwood Road. With entrance relocation, site land cover values and BMP options (type, size, location) may change. (Rev. 1) Addressed. Applicant Response: `We have altered the site design to coordinate with the Brookdale project on the adjacent site. This primarily involved removing the connection to Mountainwood road. Engineering Review Comments Page 2 of 7 • The proposed release point of the biofilter is within an existing swale within our property. The approved Brookdale VSMP plan accounted for this swale, and the runoff it collects, in the sizing of their SWM detention basin. Since our biofilter outlet meets the energy balance equation at this point, this compliance dictates that runoff from our site will not cause additional impact to this neighboring site. We have contacted the design engineers to negotiate a grading easement so that we can continue the swale into the basin and prevent any long-term erosion. • After discussion with VDOT staff we have elected to remove the connection to Mountainwood Road and include a turnaround in the private travelway. SWM calculations have been updated to reflect this change.' As follow-up: • Private travelway is a public road by default, unless approved as a private street. In either case, access to subdivision requires a Road Plan. (Private street request procedures listed at 14-232.) • Road /street must meet VDOT standards. This road /street likely qualifies for AASHTO 2001 Guidelines for Geometric Design of Very Low -Volume Local Roads. Ref. excerpt, Exhibit 3, U.S. Customary (unit of measure), when designing public road /private street (25mph design speed). 90' CL radius does not meet minimum CL radius. Engineering anticipates change in impervious area, slight change in calculated runoff values, and VSMP Plan revision. (Attached.) • Revise cul-de-sac: Design does not meet (typical) Albemarle Fire -Rescue min. required cul-de-sac radius (48'). Recommend Applicant coordinate cul-de-sac Min. radius with Fire -Rescue prior to Road Plan submittal, and to coordinate with ACPS Director of Transportation to confirm there is no prospect (zero potential) of future public school transportation (K-12) bus routes that use Royal Fern internal road/s. Without written confirmation from both ACPS and Fire -Rescue, provide Min. cul-de-sac radius 45' on Road Plan (when submitted) and revised VSMP resubmittal. Ref. VDOT Road Design Manual, Appendix B(1), B-4, Elements of Typical Section, F. (text image) F. CUL-DE-SACS AND TURNAROUNDS 1. To afford the greatest flexibility in design, various types of turnaround designs may be used on subdivision streets. Additional right-of-way shall be provided as required by the turnaround design to continue the right of way limits around the perimeter of the turnaround. Acceptable Cul-de-sac designs include: B-17 a. Circular Type Turnarounds For circular turnarounds, a well-defined identifiable street segment, equal to the normal lot width along the intersected street that serves the cul-de- sac or 50 feet whichever is greater, shall extend from the intersected street to the turning area. A minimum radius of 45' feet, measured to the edge of pavement or face of curb, shall be used for circular turnarounds on residential cul-de-sac streets serving more than 25 dwellings and greater than 0.25 mile in length. A 45 foot radius should also be used If standard 65 passenger school buses are expected to use the cul de sac, or for any nonresidential use. For circular turnarounds on short low volume residential cul-de-sac streets, this minimum radius may be reduced to 30 feet when specifically approved by the locality in consultation with Imergency services. • When designing shoulder and ditch section, please ref. VDOT Road Design Manual, Appendix B(1), B-3, Roadway Geometric Design Criteria, Table 2, for Min. ditch width. This section applies to all lots, even those with relatively flat grade. Ditches convey runoff, and limit ponding. Driveway entrance pipes are required whenever there is a design vertical change in grade (elevation) as measured at either side of a driveway, however slight. 2. If revised VSMP design proposes Forest /Open Space Easement, and multiple areas combine to provide a total post -development land cover forest /open space acreage, label each section of Forest /Open Space Engineering Review Comments Page 3 of 7 Easement. (Rev. 1) Partially addressed. As follow-up: 0.40 Ac. portion of proposed 1.18 Ac. overall Forest /Open Space easement, which fronts Country Green Road, is not entirely eligible. (Other sections are also ineligible.) DEQ guidance affects eligibility. Practical concern over future disturbance and lessons learned through experience allowing Forest /Open Space on private lots (Chesterfield Landing) lend support to protective barrier requirement as condition of acceptance of even a portion of proposed 0.40 Ac. section as Forest /Open Space easement. Design proposes permanent easements that prohibit all but occasional use or maintenance of sections of seven lots (Lots 2-8). Initial SWM Forest /Open Space easement will not be between Albemarle and eventual owners of lots (who will likely be unaware, barring close examination of final plat, that limits apply to the property), but instead, between Albemarle and developer. In the VaRRM .xls, if —0.1 Open Space C is included with 0.78 Ac. portions of SWM Forest /Open Space easement west of the proposed road /street (which are likewise partially ineligible), and these values entered in the .xls, the phosphorus load reduction required for the development rises from 1.58 to 1.70 lb./yr. At current market rates of $14k /lb., this is approximately $1,680, or $240/Lot. • For all portions of proposed SWM Forest /Open Space Easement, per DEQ Guidance Memo No. 16-2001, Undated Virginia Runoff Reduction Method Compliance Spreadsheets — Version 3.0, d. May 2, 2016 (link: hM2s://www.vwrrc.vt.edu/swc/documents/GM16- 2001%20Virginia%20Runoff%20Reduction%20Method_V3.pdf), p. 12, Table 1, Land Cover Guidance for VaRRM Compliance Spreadsheets, Forest & Open Space: o Compare Site Layout with Grading and Utility Plan. Any area disturbed or not protected during construction of individual lots or common areas, east or west of road/street, is ineligible for Forest /Open Space classification or inclusion in VaRRM .xls. Remove all disturbed or unprotected areas from proposed Forest /Open Space (.xls) Land Cover Acreage. Revise plans. o For eligible areas, coordinate effect of proposed SWM Forest /Open Space easement with current OHU easement holder. Confirm SWM Forest /Open Space easement may overlap Ex. OHU easement. Examine legal aspect, such that easement relied upon for stormwater management compliance is not now (nor will be) compromised by occupying space under existing easement. Written declaration by Ex. OHU easement holder `No conflict exists' between proposed Forest /Open Space and Ex. OHU easement is requisite to acceptance of any portion of proposed Forest /Open Space easement proposed to be located on undisturbed, protected portions of the subdivision, and co -located on areas shown to be under Ex. OHU (or other) easement. o For eligible areas proposed to be located on Lots 2-8: provide protective permanent barrier, a fence not shrubs (12" dia./24-30" deep concrete base/ea. post; pressure treated or galvanized material, 6' ht., with gated access to Forest /Open Space portion of lot). Estimate —500-ft fence required, Lots 2-8. (Compare with $1,680. Can fence be installed for $3.36 /ft.? Will fence enhance property values?) o Revise VaRRM .xls, as needed. E., Ee /Pond-Let-2.-atiens(Imae€) /image removed with Rev.l review: Royal Fem: Proposed Entrance /BMP Location, AT0201800044 (Excerpt, sheet Q) 3�r 'I OPfM1SPACEB J r �f OPM SPACE U III 3. 4. 5. 10 Engineering Review Comments Page 4 of 7 DEQ Guidance Memo No. 16-2001, p. 12, Table 1, Land Cover Guidance for VaRRM Compliance Spreadsheets, Forest & Open Space: Virginia Runoff Reduction Method Compliance Spreadsheet April2016 Table 1. Land Cover Guidance for VRRM Compliance Spreadsheets FOREST & OPEN SPACE Land that will remain undisturbed OR restored to a hydrologically functional state': • Portions of residential lots that will NOT be disturbed during construction • Portions of roadway rights -of -way that, folfowing construction, will be used as filter strips, grass channels, or stormwater treatment areas; MUST include soil restoration or placement of engineered soil mix as per design specifications • Community open space areas that will not be mowed routinely, but left in a natural vegetated state (can include areas bush hogged no more than four times per year) • Utility rights -of -way that will be left in a natural vegetated state (can include areas bush hogged no more than four limes per year) • Surface area of stormwater BMPs that are NOT wet ponds, have some type of vegetative cover, and that do not replace an otherwise impervious surface o BMPs in this category include bioretention, dry swage, grass channel, extended detention (ED) pond that is not mowed routinely, stormwater wetland, soil amended areas that are vegetated, and infiltration practices that have a vegetated cover Other areas of existing forest andlor open space, including wetlands, that will be protected during construction and that will remain undisturbed Operational & management conditions for land cover in Forest & Open Space category: • Undisturbed portions of yards, community open space, and other areas that will be considered as forestlopen space must be shown outside the limits of disturbance (LOD) on approved erosion and sediment control plans AND demarcated in the field (e.g., fencing) prior to commencement of construction • Portions of roadway rights -of -way that will count as forestiopen space are assumed to be disturbed during construction, and must follow the most recent design specifications for soil restoration and, if applicable, site reforestation, as well as other relevant specifications if the area will be used as a filter strip, grass channel, bioretention, or other BMP • All areas that will be considered forest/open space for stormwater purposes must have documentation that prescribes that the area will remain in a natural, vegetated state o Appropriate documentation includes: subdivision covenants and restrictions, deeded operation and maintenance agreements and plans, parcel of common ownership with maintenance plan, third -party protective easement, within public right-of-way or easement with maintenance plan, or other documentation approved by the local program authority • Although the goal is to have forestlopen space areas remain undisturbed, some activities may be prescribed in the appropriate documentation, as approved by the local program authority: Lots 8, 9, 10 appear to propose portions of building sites on critical slopes; ref. 18-4.2.1(a). Relocate building sites off managed steep slopes, as underlying district includes critical slope restrictions. (Rev. 1) Withdrawn —review error. C2, C4: Label steep slopes. (Rev. 1) Addressed. Provide VSWMH Appendix C (periodic) BMP facility inspection checklist/s on the plans. Engineering has .PDF files of each Appendix C checklist, and will provide to Applicant on request. (Rev. 1) Addressed. Provide construction steps copied directly from VA Stomrwater Design Specifications, for each proposed BMP facility. (Rev. 1) Addressed. 0: Title this sheet Site Layout. (Rev. 1) Addressed. C3, BMP outfall: Provide drainage easement that extends to a natural receiving channel. It is insufficient to locate proposed outfall coincident with a property line without release to a natural or manmade channel. (14-431.A.1.) (Rev. 1) Addressed. Applicant response: `We have contacted the deisgn engineer of the adjacent site plan to provide a grading easement to extend the existing swale into their proposed SWM basin. The proposed swale would be located within the SWM easement on that property.' Note: Ditch 9 (Sheet C3) would require adjacent property owner to be listed on ESC Plan bond, so ditch 9 soil stabilization matting will not be included in ESC bond estimate for Royal Fern. C3: Extend SWM Access easement to a public right-of-way, over and across proposed private streets. (Rev. 1) Addressed. C3: Relocate BMP Access Easement so not coincident with ditch 9. BMP access must provide vehicular Engineering Review Comments Page 5 of 7 access; ditch and access may not occupy the same corridor space. ^nCT'�o@6. 5, p. 12: (Rev. 1) Addressed. 11. Since property to the west has right to develop under FSP SDP201700069, recommend consider working with adjacent property owner to route Royal Fern runoff to a proposed manmade drainage system; i.e., MH. (Rev. 1) Addressed —refer to previous comments on this point. 12. Design must meet VAC25-840-40.19.(a.-n.) (MS-19) (Rev. 1) Addressed/acknowledged. 13. Any Forest/Open Space Easement relied upon for water quality compliance must be recorded with final subdivision plat as condition of VSMP Approval. (Rev. 1) Addressed/Noted. Also, comment #2, above. 14. C5, Stormwater Management Note 1. is, for the moment, inaccurate. Revise design. Also, item #1, above. (Rev. 1) Addressed. 15. Compare C5, SWM Note. 4 (1.23 Ac.) with C3 proposed Forest /Open Space Easement Area (1.25 Ac.); revise for consistency. This and many comments may be irrelevant with redesign. (Rev. 1) Addressed. As follow-up: Revised to 1.18 Ac., but see comment #2, above. 16. Ensure BMP Notes with salient details (C5) appear as labels on BMP profile; 7" pond depth, for example. (Rev. 1) Addressed. 17. C5 Biofilter Installation Notes: for any proposed BMP, copy installation /construction steps from the appropriate VA Stormwater Design Specification. List specification installation steps on the plans. (Rev. 1) Addressed. 18. Strongly recommend VSMP plan show future developed condition of adjacent TMP # 76-46C1, since this development is approved (Brookdale). (Rev. 1) Addressed. 19. C2, Provide TMPs for adjacent parcels. (Rev. 1) Addressed. D. Erosion and Sediment Control Plan (ESOP) Virginia Code §62.1-44.15:55 requires the VESCP authority to approve or disapprove an ESOP. This plan is disapproved, for reasons listed in comments, below. The erosion control plan content requirements can be found in County Code section 17-402. C6 1. Label CE as PCE —Revise Legend to include Paved Construction Entrance. (Rev. 1) Addressed. 2. Label Country Green Road. (Rev. 1) Addressed. 3. Show Ex. treeline. (Rev. 1) Addressed. Note: Areas presently in forest (Ex. trees) proposed to be removed with SWM facility, road, or other development feature construction are ineligible to be considered SWM Forest /Open Space easement. Also, comment 42, above. Label LOD Area =4.30 Ac. (Rev. 1) Addressed. As follow-up: Ensure SWPPP Sec. 1 Registration Engineering Review Comments Page 6 of 7 Statement Area to be Disturbed (12.40 Ac.) and VSMP Plan LOD (C7, ESC Legend, 4.00 Ac.) match. 5. Provide additional contour labels. (Rev. 1) Addressed. 6. Add SAF to legend (dash -square -dash). (Rev. 1) Addressed. 7. Add TP to legend /show tree protection, as/where needed. (Rev. 1) Addressed. C7: (Less relevant,e desien Lwill eh o) 8. Provide floor dimensions, proposed biofilter. (Rev. 1) Not addressed (unless review error). Please label biofilter L X W on sheet C4. 9. Provide additional contour labels to aid review. (Rev. 1) Addressed. 10. Lots 6, 7, 8, 10 require driveway entrance pipes. (Rev. 1) Not addressed. Applicant response: `Lots 6, 7, 8, 10 will have driveways that are graded to have a slight swale to direct runoff. These driveways do not pass over a defined ditch, so culverts are not needed.' Please ref. SWM Plan comment #1, follow-up, 4' bullet. Driveway design shown on Road Plan and ditch design shown on VSMP Plan is compared with VDOT Road Design manual, Table 2, shoulder and ditch section. Elimination of ditches does not meet VDOT standards. A defined ditch is shown on C4; a ditch is required by VDOT Road Design Manual. 11. Label ditches to receive EC-2 stabilization blanket. Provide ref. to C9 detail. (Rev. 1) Addressed. 12. Provide label and dimensions for timber /gravel level spreaders. Provide typ. detail. (Rev. 1) Addressed. 13. C8: Check sediment trap 2 table values: A, B, C, H values may require revision. (Rev. 1) Addressed. C9: 14. Dimension BMP outfall riprap (L X W X D). (Rev. 1) Addressed. 15. Storm Sewer Profile B 1-132: 6" roof drain in —show in plan view; or confirm shown on site plan. (Rev. 1) Addressed. Asfollow-up: Compare plan labels to profile labels; profile labels transposed. Please revise. 16. Storm Sewer Profile C 1-C2: Label pipe slope. (Rev. 1) Addressed. 17. Storm Sewer Profile CI-C2: Revise rim elevation 48" cone. riser to 460'. (Rev. 1) Addressed. The VSMP permit application and all plans may be resubmitted for approval when all comments have been satisfactorily addressed. For re -submittal, please provide two 2 copies of the VSMP Plan with a completed application form. Note: There is no need to resubmit the SWPPP until SWM and ESC plans are approved. Engineering plan review staff are available from 2-4 PM on Thursdays, should you require a meeting to discuss this review. Process After approval, plans will need to be bonded. The bonding process is begun by submitting a bond estimate request form and fee to the Department of Community Development. One of the plan reviewers will prepare estimates and check parcel and easement information based on the approved plans. The County's Management Analyst will prepare bond agreement forms, which will need to be completed by the owner and submitted along with cash, certificates or sureties for the amounts specified. The agreements will need to be approved and signed by the County Attorney and County Engineer. This may take 2-4 weeks to obtain all the correct signatures and forms. Stormwater Management Facilities Maintenance agreements will also need to be completed and recorded. The County's Management Analyst or other staff will prepare the forms and check for ownership and signature information. The completed forms will need to be submitted along with court recording fees. Stormwater Management Facility, SWM Facility Access, Forest /Open -Space Easements must be recorded with the final subdivision plat. Subdivision plat will not be approved unless it shows all easements required to approve the VSMP. This means a Grading Permit may be issued prior to recordation of VSMP-related easements, with final plat. After bonding and agreements are complete, county staff will need to enter project information in a DEQ database for state application processing. DEQ will review the application information based on local VSMP authority approval. At this time, the DEQ portion of the application fees will need to be paid directly to the state. For fastest processing, this is done electronically with the emails provided on the application. DEQ should notify applicants with instructions on how to pay fees. When DEQ approves the application, they will issue a permit coverage letter. Engineering Review Comments Page 7 of 7 This should be copied to the county. After DEQ coverage is issued, via the coverage letter, the County can hold a pre -construction conference. Applicants will need to complete the request for a pre -construction conference form, and pay the remainder of the application fee. The form identifies the contractor and responsible land disturber, and the fee remaining to be paid. This will be checked by county staff, and upon approval, a pre -construction conference will be scheduled with the County inspector. At the pre -construction conference, should everything proceed satisfactorily, a joint VSMP and grading permit will be issued by the County so that work may begin. County forms can be found on the county website forms center under engineering; http://www.albemarle.org/deptforms.asp?department=cdengwUo File: WPO201800044 Royal Fern_101018 revl.doc