HomeMy WebLinkAboutSUB202000191 Review Comments Preliminary Plat 2020-12-02
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Preliminary Plat review
Project: Jarmans Gap Development TMP-55-77-A1 –Preliminary Plat
Project file number: SUB202000191
Plan preparer: Scott Collins; Collins Engineering [200 Garrett St., Suite K, Charlottesville, V A
22902, scott@collins-engineering.com]
Owner or rep.: James R. Jackson, Jr. / 6107 Jarmans Gap Road, Crozet, VA 22932
Plan received date: 6 Nov 2020
Date of comments: 2 Dec 2020
Reviewer: John Anderson
Project Coordinator: Paty Saternye
Engineering has reviewed the preliminary plat, and offers the following ( for Final plat approval):
1. Proposed 4’ segmented retaining wall requires:
a. A building permit,
b. PE-sealed design, and
c. A recorded wall maintenance easement agreement between owners of Lot 4 and Lot 5. Deed bk.-
pg. reference to recorded agreement is required prior to or with Final plat. Agreement may be
recorded with the Final plat.
2. An approved WPO plan is required prior to final plat approval. Please submit WPO plan application at
earliest convenience.
a. Note: With WPO plan, extend discharge from proposed SWM facility to a natural or man-made
storm conveyance system. It may not be discharge to ungraded non-defined general slope
contours. Please see 9VAC25-870-66.B., Channel protection, first sentence: ‘Concentrated
stormwater flow shall be released into a stormwater conveyance system…’ This statement applies
to discharge at any point, to any point.
b. Recommend extend swale riprap outfall cross-contour further south along eastern edge of Lot 4 to
the point it intersects an apparent defined natural channel on Lot 4. Else, it appears a permanent
off-site public drainage easement across TMP 55E-03-B is required. See image below: solid blue
line =possible location of riprap extension across Lot 4 (manmade conveyance) to apparent point
of intersection with natural conveyance (indicated by existing contours, which then lead to stream
on TMP 55E-03-B). Dash blue line ≈ point of intersection of riprap (extension) with natural
conveyance on Lot 4, with no off-site easement required. Off-site erosion /inadequate conveyance
may pose recurrent or difficult-to-resolve post-construction issues. Design must convey post-
developed runoff to a natural or manmade stormwater conveyance system at each point upslope of
eventual, final off-site natural or manmade conveyance system.
c. Provide VaRRM.xls.
Engineering Review Comments
Page 2 of 4
3. An approved road plan is required prior to final plat approval. Please submit road plan application at
earliest convenience. With road plan, please ensure /provide:
a. Runoff to the west edge of the proposed public road from Jarmans Gap Road into the development
is collected and conveyed via storm conveyance, with remnant runoff discharged directly to parcel
to the west as non-concentrated sheet flow.
b. LD-204, LD-229 tables, hydraulic design calculations.
c. Plan /profile of storm collection /conveyance systems.
d. Pavement design; projected ADT.
e. Dp, Dr, needed to support item 3.d., above.
f. CG-6 wherever runoff concentrates against curbing.
Sheet 3
4. With WPO Plan, if SWM facility is designed as a swale, please ref. swale design criteria, including
longitudinal slope, etc. At first glance, SWM facility is oblong without clear swale length or width
characteristics. It appears more nearly a simple detention basin. Please ensure proposed design nets
intended water quality credits, by meeting VA DEQ Stormwater Design Criteria.
5. Revise Lot 5 lateral transit of Lot 4 to avoid proposed 4’ segmented retaining wall (current design does
this) to then approach Lot 4 lot line; that is, revise lateral location to run parallel with Lot 4 lot line within
landward 50’ of stream buffer to avoid dwelling construction conflict/s on Lot 4. Lot 5 private sanitary
lateral should lie as nearly as possible to Lot 4 lot line as practical (5’-10’ offset) in a private easement
centered over Lot 5 lateral as it crosses Lot 4. Engineering recommends ~8’ offset from Lot 4 eastern lot
line. This location is permissible under 17-604.A, with definition of sewage disposal system excluding
lateral pipes from a dwelling unit to a publicly owned sewerage facility . An alternative location near lot
line is required to allow reasonable use of Lot 4 and 5. Engineering does not object to Lot 5 sanitary lateral
location that avoids proposed retaining wall and that lies as close a s 5’ to Lot 4 eastern lot line.
Engineering Review Comments
Page 3 of 4
Image illustrates comment:
Engineering Review Comments
Page 4 of 4
6. Lot 1: Similar to item 5: Please relocate Lot 1 sanitary sewer lateral near /within Lot 2 side setback to
minimize potential future Lot 2 building site conflict/s. Provide and record a private sanitary sewer lateral
easement for Lot 1, across Lot 2. Easement may be recorded with final subdivision plat. See image, below.
7. Provide additional existing and proposed contour labels (with WPO /Road plans) west of proposed
(development access) public road, near Jarmans Gap Road.
8. With 25’ radius return ending at adjacent property line, acquire and provide copy of recorded temporary
construction easement needed to construct curb, sidewalk, and proposed grade. Alternatively, furnish right-
of-entry letter (ROE) or similar legally-enforceable written agreement that grants developer right to occupy
adjacent parcel in areas, as needed, for temporary constructive purposes.
Please feel free to call if any questions: 434.296-5832 -x3069.
Thank you
SUB202000191 Jarmans Gap Rd Devp TMP 55-77A1 PPT 120220