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HomeMy WebLinkAboutSUB201700187 Review Comments Road Plan and Comps. 2019-08-01COUNTY OF ALBEMARLE Department of Community Development 401 McIntire Road, Room 227 Charlottesville, Virginia 22902-4596 Phone (434) 296-5832 Fax (434) 972-4126 Road and Drainage plan review Project title: Crozet Court Project file number: SUB201700187 Plan preparer: Shimp Engineering [Justin@shimp-engineering.com] Owner or rep.: Stony Point Design/Build LLC Chris Henry [chenry@stonypointdb.com] Date Received: 1 November 2017 (Rev. 1) 5 Jul 2018 (Rev. 2) 5 Feb 2019 (Rev. 2) (Rev. 3) 1 Apr 2019 (Rev. 4) 31 Jul 2019 Date of comments: 15 December 2017 (Rev. 1) 31 Jul 2018 (Rev. 2) 9 Mar 2019 (Rev. 2) (Rev. 3) 22 May 2019 (Rev. 4) 1 Aug 2019 Reviewer: Matt Wentland John Anderson (Rev. I - 4) Keane, we have reviewed the road plans and have the following comments: Engineering 1. It is not clear how the flow from the 15" CMP under Claudius Ct. next to the proposed entrance will reach the inlet on Lot 17. Provide more detailed grading in this area to verify the neighboring property will be unaffected by the Jamestown Road construction. (Rev. 1) Pending. Met with Applicant on 7/12/18 to discuss bypass flow. See Engineering email: 7/18/2018 8:30 AM. (Rev. 2) Not addressed. Grading Plan, C5, must include entire development and likely requires a separate grading sheet with drawing scale needed to construct ditch 4A to eliminate development or drainage impact to TMP #56D-A-5, Ralston (recommend F-0" contours; 1 "=10' scale inset drawing). Ditch 1 must be included in the grading plan, not just C8, Landscape Plan. (Rev. 3) Partially addressed. As follow-up: Show proposed grading at 1' intervals to avoid potential impact to Ralston parcel. Options: Provide I' proposed contours for Ditch 4A, C5 inset, along boundary of TMP #56D-A-5, or a series of Ditch 4A spot elevations at 3 or more points to define ditch cross section (left, right, center) so that adequate design elevations inform construction to help minimize offsite design event storm impact to an adjacent property owner who has contacted Albemarle County throughout the design process. This request for design elevations is required for plan approval. (Rev. 4) Partially addressed. Asfollow-up: Please label 38 LF 18" DIA culvert pipe beneath pedestrian /emergency vehicle connection between cul-de-sac and Claudius Court. Please provide storm line profile for grate inlet, VDOT ES-1, and 38' pipe. Note: Engineering appreciates SE coordinating SSAR waiver request with VDOT (design provides turnaround). VDOT approved SSAR connection waiver request via letter d. 7/25/19. ACF&R may request revision to 30' R cul-de-sac to accommodate fire rescue vehicles. Engineering defers to Fire Marshal /ACF&R /VDOT on cul-de-sac turnaround minimum radius. 2. Show easements on all the proposed ditches and pipes. (Rev. 1) Addressed. Asfollow-up, provide sight distance and segmental block retaining wall maintenance easement (portion of wall is in Open Space Parcel A). Engineering recommends Maintenance Easement cover entire wall, as this wall ensures no disturbance to existing cemetery, a prerequisite to development. (Rev. 2) Partially addressed. Asfollow-up: Wall Easement, C3, is slightly outside physical face of wall, but so limited as to provide inadequate access for Engineering Review Comments Page 2 of 6 virtually any required maintenance or replacement. Increase wall easement width to provide normal access, and to accommodate typical routine repair, maintenance, or replacement. Estimate need 12'f space either side of the 8' segmental block retaining wall (but less at known limits of cemetery, and to exclude cemetery). (Rev. 3) Partially addressed. Applicant response: `We looked into retaining wall easements for other subdivisions and found that maintenance for retaining walls is covered in HOA bylaws. Otherwise, the developer would be unable to sell lots containing retaining walls because no single homeowner would want the financial responsibility of wall maintenance. As such, we removed the retaining wall easement. The Crozet Ct. HOA bylaws will grant full access for maintenance of this wall. We added a note about Maintenance on Sheet C1, "Subdivision and Road Notes," #I L' As follow-up: a. Provide copy of (draft) Crozet Court bylaws. Engineering retains interest in public safety aspect of retaining walls on residential lots, especially during construction. (Rev. 4) Withdrawn. Engineering defers to Planning. b. Not strictly related, provide access easement for descendants of the interred at existing cemetery (Lot 22) as required by Virginia state law (§ 57-27.1). Access must extend from public R/W to cemetery. (Rev. 4) Addressed. c. Engineering appreciates Applicant's level of research and rationale. 3. Provide Deed Book references or copies of signed agreements for any off -site construction easements (such as on the 960 Claudius Ct. property). (Rev. 1) Addressed. Applicant response: No off -site construction is proposed. New 4. Revise Road Plan title to include SUB201700187. (Rev. 2) Addressed. 5. Title /C1: Revise Subdivision and Road Note #2 to reference Open Space labeled as A on sheet 3. (Rev. 2) Addressed. 6. Title /C1: Reference Subdivision and Road Note #9: Revise design to reflect 25 mph. Delete reference to 20 mph design. Revise accordingly, Min. Ksag, etc. (Rev. 2) Not addressed. Applicant response: `Jamestown road will function primarily as an emergency access road. We predict that almost no residents will use this road because it does not directly connect to Park Road, the access road to the entire neighborhood, therefore, Jamestown Road is out of the way and would cause a longer trip for each house in the proposed Crozet Court subdivision. This road serves as a secondary connection for emergency vehicles, and thus we have designed it with a design speed of 15 mph.' Engineering rejects this rationale. Jamestown is a public road. Future development in the Crozet area may make Jamestown a preferred route for subdivision access to or from points east (with construction of the eastern connector, for example). Delivery vehicles may use Jamestown Road with high frequency. VDOT design standards apply. Please consider initial review comment, and design for 25mph speed, minimum. (Rev. 3) Not addressed. Applicant response: `Jamestown Road now has a design speed of 25 mph. We kept the sag curve with an advisory speed of 15 mph, as design constraints hinder a 25mph design speed for this vertical curve. Since this is a sag curve, the limited sight distance will only prove a hindrance at night, and to add to that there will be almost no traffic using that stretch of road, an advisory speed will be sufficient to provide adequate safety at the sag. See note 30, below for additional detail.' Asefollow-up: Engineering principles ensure safety, consider typical and unusual circumstance, and specify standards that consider a range of factors, including visibility under varying conditions. Rev. 2 review comments reject rationale that repeats with this revision. VDOT standards for a proposed public road do not, to our knowledge, provide exception that if allowed may compromise safety only at night. Albemarle restates requirement for Min. Ksag for approval. (Rev. 4) Withdrawn. A pedestrian /emergency vehicle connection will be built. Revised design provides Fire Apparatus Road section and Concrete Grid Paver Fire -lane detail (C9). C3 7. Label roadway PC, PT, radius of horizontal curvature. (Rev. 2) Not addressed. Show requested design information on C3, Layout Plan. (Rev. 3) Partially addressed. Asfollow-up: Please provide conventional PC labels on roadway centerlines, and adopt convention and list horizontal curvature on roadway centerline, especially 752.9' R, Agatha Lane. (Rev. 4) Addressed. 8. Provide roadway stationing. (Rev. 2) Not addressed. Provide on C3. Appreciate stationing on C6 and C7, but stationing on C3 is required. (Rev. 3) Addressed. 9. Label CG-6 turndowns at intersection with Park Street and Claudius Court. (Rev. 2) Not addressed. Show Engineering Review Comments Page 3 of 6 on C31 even if shown elsewhere. (Rev. 3) Addressed. 10. Provide detail for CG-6 taper from 6" height to flush (0" height /turndown). (Rev. 2) Not addressed. Applicant response: `Additional detail added.' Cannot locate detail on plans. Specify sheet with this detail. (Rev. 3) Addressed. 11. Show residential driveway entrance aprons accurately (CG-913). Entrances shown are inaccurate, and may be misleading. (Rev. 2) Not addressed. (Rev. 3) Not addressed. Applicant response: `We have left the curb cuts like this to allow for variability within each lot's final house plans and because it is easier for us to make changes to plans with the driveways drawn as shown. The plan as shown lets the road contractor know where to place curb cuts, but allows the individual home builder the option to choose 8' or 16' driveway widths. We understand this is a rough graphical estimate but have shown curb cut estimates like this in other approved plans, eg. Sparrow Hill & Chesterfield Landing, and contractors will know by individual lot plans, and via inclusion of CG-9B detail, where to build the radius for each entrance.' As follow-up: While response appears reasonable, in practical terms it has failed. The subdivisions mentioned were visited by problems during construction that may relate in part to less than definite design elements. Chesterfield Landing (contractor) relocated a drive entrance that eliminated a CG-12 ramp and street tree/s. Also at Chesterfield, drainage elements were revised or not built in accordance with approved plans. Taking lessons from these subdivisions, it appears important to provide sufficient graphic detail of applicable standards to ensure design intent is not lost on contractors who at times may inadvertently revise design to the point it obscures or compromises standards during construction. While it may be easier to leave certain details off plans, experience guides that design should reflect standards, clearly if possible. Revise driveway entrances shown on C3 to reflect VDOT standard geometries, including width and radius. Pg. 21, ACDSM may be helpful: (Rev. 4) Addressed. I. Driveways: Driveways in the rural areas must meet requirements of the Zoning Ordinance, section 184.6.6. Driveways follow the VDOT standards in the right-of-way, and general safety and access provisions of the zoning ordinance and building code as administered by the agent, the zoning administrator and the building official. The Zoning Administrator has a policy regarding adequate access before certificates of occupancy can be issued, and this policy is available from zoning officials. 12. Provide 6" wide solid white pavement markings with VDOT spec. for pavement markings, at each proposed CG-12 crosswalk (5, total). (Rev. 2) Comment withdrawn. Applicant response: `VDOT did not request this, we do not typically see this in subdivision street crosswalks.' Ref. Albemarle County Engineer email to plan review staff, 3/8/2019 9:47 AM: "The road plan for Uut of Bounds showed crosswalk striping where the short private roads intersected the main public road and at a crossing that crossed the public road. VDOT accepted the pubiic road without requiring the striping for their road. [NAME} asked if the striping was required for the short private road connections, stating there is very little traffic. I agreed and it appears VDOT agrees striping isn't required or preferred for small developments." 13. Show and label extents of cemetery. Provide and show permanent barrier protection on VSMP /WPO and across road plan sheets to avoid mishap. Clearly label cemetery boundary. (Rev. 2) Addressed. 14. Show sight distance triangles. Provide sight distance easement/s, as needed. (Rev. 2) Partially addressed. Label sight distance lines on C6 and C8 (Park Rd. -Park Place Int.). Provide and label sight distance lines at intersection Jamestown Road and Park Place, C6. Provide and label sight distance lines at intersection Jamestown Road and Claudius Court, C7. (Rev. 3) Partially addressed. Asfollow-up: C9/10 sight line profile for Agatha Lane — Park Road Int. shows 280' sight line touching existing Park Road at Sta. 13+50. Similarly, Jamestown Road — Claudius Court Int. 280' sight distance line is within 2"-3" of Claudius Ct. roadway surface. Confirm via field survey that sight line profiles in neither instance is obstructed by existing terrain (Park Road /Claudius Ct.). Last: Show parcel boundaries of lots fronting Claudius Ct. Provide sight line easements for portions of sight line/s that cross boundaries as appears to be the case at both intersections. Sight distance easements must be recorded with (or prior to) the final plat (approval). Last, renumber second sheet C9 as sheet C10. (Rev. 4) Comment substantially withdrawn ollow-u ). Design revised to provide pedestrian /emergency vehicle access only at Jamestown Road points in question. As follow-up: Please provide sight distance easement (Agatha Ridge Lane /Park Road Int. with subdivision plat) as condition of final Road Plan approval. C4 Engineering Review Comments Page 4 of 6 15. Label A2 — Al pipe diameter /pipe material. (Rev. 2) Addressed. 16. Label E2 — E1 pipe diameter /pipe material. (Rev. 2) Addressed. 17. Revise E3 — E2 pipe diameter to 18". LD-229 shows this pipe at 98.3% of capacity, too close to capacity threshold. (Rev. 2) Comment withdrawn. Note to designer; from Drainage Plan checklist: "A drainage plans is typically a component of a road plan, site plan, or stormwater management plan. ` Applicant response: Biofilter outlet pipe is dependent on biofilter design per HydroCAD model. This is not governed by VDOT pipe requirements since it does not convey water from the street, therefore size will be kept.' It appears that with this road plan, and recent site plan, county review comments have elicited a striking response. While fair to question authority, purpose of comments is largely to ensure compliance with standards designed to protect life and property. If design wishes to proceed at 98.3% of capacity against Engineering request, if P.E. is willing to seal plans and transfer repair responsibility to the development community (HOA, so be it, but please be advised: Drainage Plan checklist specifically cites VDOT drainage manual (Drainage, item 2) in context of road, site, and SWM plans. Design is not free to reject VDOT requirements, review checklists, or safe and reliable performance. If designer insists on design at 98.3% of Qlo_r= pipe capacity, Engineering cautions against avoidable risk. (Rev 3) Addressed. Applicant response: `Addressed, hydraulics for the biofilter spillway system was designed and reviewed using the HydroCAD software, which has more detail and nuance for basin design than the LD-229. The HydroCAD model had showed that 15" barrels were sufficient. Nonetheless, the outlet pipes have been increased to 18". 18. Revise E2 — E 1 pipe diameter to 18", consistent with sheet C 12, outlet table, and storm line profile. Also, LD-229 shows this pipe at 98.3% of capacity, which is unacceptable. With no margin of error, apply conservative design principles. (Rev. 2) Comment withdrawn. Ref. item 17, above. 19. Revise B2 — B 1 pipe diameter to 18", consistent with sheet C 12, outlet table. (Rev. 2) Comment NA. 20. Revise design at Str. A4: Departing pipe to Str. A3 forms acute angle with inlet pipe from Str. A4A. (Ref. Drainage Checklist /Drainage item #9 direction of flow change.) (Rev. 2) Addressed. 21. Overreliance on 15" DIA drainage pipes violates drainage computation checklist item #1: "All proposed systems are designed within open channel flow capacities. (HGL computations are not necessary, and should not be relied upon unless the entire system is to be watertight)." If system is to be watertight, provide necessary specifications and details for pipe and MH joints; gasket material, installation guidelines and inspection, etc. The following structures have inlet water elevation higher than top of pipe: A5, A4, A2, B5, B4, B3, B2. (Rev. 2) Addressed. 22. VDOT Drainage Calculation Packet: provide LD-347 for C-series pipes. (Rev. 2) Pending. Please submit .PDF of revised VDOT Drainage Calculation Packet. Print copy may have become separated from print plans. Engineering will review within 3 days of receipt, and update comments. Regret any inconvenience. (Rev. 3) Addressed. 23. LD-204 shows inlet depth, Str. A5=0.91'. If accurate, revise so that depth at curb <0.375'. (Rev. 2) Pending. Please submit .PDF of revised VDOT Drainage Calculation Packet. Print copy may have become separated from print plans. Engineering will review within 3 days of receipt, and update comments. Regret any inconvenience. (Rev. 3) Addressed. As follow-up: Compare Calc. packet Modified LD-268 (tables, last 2 pp. of packet) with each other, and with Detail 9, C13. The tables appear to be identical, but there are slight variations in values. Please clarify why values differ. Tables are also inconsistent with Detail 9, C13, Typical Ditch Details (Lining /10-year flow depth). Revise packet /plan for consistency. (Rev. 4) Addressed. 24. Show graded ditch line on north side of Jamestown Road between Claudius Court and Lot 17 (also, item #1, above), per 7/12 discussion, and 7/18 Engineering email. (Rev. 2) Not addressed. Insufficient detail. Also, please see item 1, above. (Rev. 3) Not addressed. Also, please see item 1, above. (Rev. 4) Addressed. C5: 25. Ref. item #24; show orn(Iina (Rev. 2) Not addressed. Also, item 1, above. (Rev. 3) Not addressed. Also, item 1, above (Rev. 4) Addressed. 26. Extend existing terrain contours at least 50' beyond property lines. (Rev. 2) Comment withdrawn. Applicant response: `We do not have this survey data. We do not typically have this as it is on other properties which we do not have access to.' Reviewer unable to cite requirement supporting request. Engineering Review Comments Page 5 of 6 27. Ditch 1 may not cross more than 3 lots. Provide yard inlet on parcel line between lot 3 and 4, and on parcel line between lot 6 and 7. Provide storm collection system from Lot 3 yard inlet to BMP A. (Ref. Drainage Checklist /Drainage item #11 —provisions and easements for drainage across 3 or more lots). (Rev. 2) Not addressed. Applicant response: `Plans revised. Ditches are in private easements.' Ref. Drainage Plan checklist, Drainage, last item: "provisions and easements for drainage across 3 or more lots. Dense development where fencing, decking, etc is expected should provide yard inlets and pipes in easements, rather than ditches." This is a standard review item; a checklist item. Provisions implies collection. Appreciate easements. Provide collection (yard inlets); revise design. (Rev. 3) Partially addressed. Applicant response: `Plans revised. Ditches only cross 2 lots now. If needed, developer can always provide additional yard drains n the easements to keep the proposed drainage, but the current plan complies with county ordinance and accomplishes proper drainage.' As follow-up: Ref. Drainage plan checklist /pg.1: `Provisions and easements for drainage across 3 or more lots. Dense development where fencing, decking, etc. is expected should provide yard inlets and pipes in easements, rather than ditches.' Checklist requirement applies to drainage, and while ditch has been revised to cross only two lots, design must provide easements for drainage, which, with proposed grading, crosses four lots. Please revise as requested with initial review. (Rev. 4) Addressed. 28. Label streets. (Rev. 2) Addressed. 29. C6, Crozet Court Profile: Provide VDOT underdrain near Int. Jamestown Rd. at Int. proposed -Ex. grade. (Rev. 2) Not addressed. County checklist requirement. Please provide underdrain at Crozet Court Sta. 13+80 and 15+00(t), else specific VDOT 2016 Road and Bridge Standard or Specification at odds with county checklist requirement. Applicant response: `Underdrains are typically not provided for streets with such low traffic per VDOT standards.' Ref. Road Plan review checklist, .44: "cross drain locations shown and labeied with VDOT designations (CD-1,2) at ever major cut and Hit transition or sag curve." Design that inadequately addresses or rejects checklist requirements may have a delayed or more difficult path to approval. (Rev. 3) Addressed. 30. CT Revise Jamestown Road profile to meet minimum Ksag value for 25 mph, AASHTO Table 3-36 /image, below. Ksag-Min.(25 MPH) =26. Note: K-value label is incorrect; proposed K =9.71. (Rev. 2) Not addressed. Applicant response: `Jamestown Road designed with speed = 15 mph, Kmin =9.4, see note 6 above.' Engineering does not accept this rationale. See item 6, above. (Rev. 3) Not addressed. Also, please see item 6, above. (Rev. 4) Addressed. Table 3-36. Design Controls for Sag Vertical Curves Metric I.S.LCustomary Design Speed (km/h) Stopping Sight Dis- tance (m) Rate of Vertical Curvature, K° Design Speed (mph) Stopping Sight Dis- tance (ft) Rate of Vertical Curvature, K° Calculated Design Calculated Design 20 20 2.1 3 15 80 9.4 10 30 35 5.1 6 20 115 16.5 17 40 50 8.5 9 25 155 25.5 26 50 65 12.2 13 30 200 36.4 37 31. C8: Relocate tree in front of Lot 8-9, which is too close to storm drain pipe. (Rev. 2) Addressed. C12: 32. Provide Typ. details for IS-1, SL-I. (Rev. 2) Addressed. 33. Check Str. B2A against Table LD-347, HGL. Compare inlet WSE=624.82 with profile Inv. Elev. 629.50'. Revise, as necessary. (Rev. 2) Pending. Please submit .PDF of revised VDOT Drainage Calculation Packet. Print copy may have become separated from print plans. Engineering will review within 3 days of receipt, and update comments. Regret any inconvenience. (Rev. 3) Addressed. 34. Label Str. B3 in profile view as requiring SL-1. (Rev. 2) Addressed. 35. Outlet protection table: La pipe outfall D1 is listed as 9' in calculation packet. Revise as necessary. (Rev. 2) Addressed. Applicant response: `It is now 34' provided to pass over the ex. sanitary pipe per ACSA request.' 36. New: Label roads, sheets C6, C7. (Rev. 3) Partially addressed. As follow-up, provide Agatha Lane label, C7. Please note County GIS request for revised road name. GIS review comment, below. (Rev. 4) Partially addressed. As follow-up, please revise C9 detail to ref. Agatha Ridge Lane. Engineering Review Comments Page 6 of 6 37. New, Rev. 3 — Engineering recommends eliminate Lot 22. Design proposes to include a cemetery within this residential lot. (Rev. 4) Withdrawn. Design /developer elect to retain Lot 22. Fire Rescue NDOT (Adam Moore) /Albemarle ARB (Margaret Maliszewski) / CDD GIS (Andrew Slack) /Planning (Cameron Langille) /ACSA (Richard Nelson) review comments will be forwarded, once received. Engineering plan review staff are available 2-4 PM on Thursdays, should you request meeting to discuss this review. Process After approval, plans will need to be bonded. County forms /checklists can be found on the county website forms center under engineering; http://www.albemarle.org/deptforms.asp?department--cdengmMo If you have questions or concerns, please contact me at janderson2@albemarle.org, or at 434-296-5832 ext. 3069. Thank you J. Anderson SUB201700187 Crozet Court Road Plans 080119rev4