HomeMy WebLinkAboutSDP202000002 Review Comments Minor Amendment 2020-04-01TIMMONS GROUP
April 1, 2020
John Anderson
County of Albemarle
Dept. of Community Development
401 McIntire Rd. Rm. 227
Charlottesville, VA. 229002
608 Preston Avenue P 434.295.5624
Suite 200 F 434.295.1800
Charlottesville, VA 22903 www.timmons.com
RE: Keswick Hall Spa — Minor Site Plan Amendment Review — SDP2020-00002 - Comment
Response Letter
Dear Mr. Anderson:
We have reviewed all of your comments from February 11, 2020 and made the necessary
revisions. Please find our responses to the comments below in bold lettering.
SDP2020-00002:
1. L3.10, Tree Planting Plan: Please show C5.1 (Grading Spot Shots Plan) storm lines as light
linework (no need to show elevations, or grade) on L3.10 to evaluate for landscape
conflicts. Trees should not occupy private drainage corridors or be shown within 5' of
private storm drain centerline (CL). For pipes within public drainage easements (i.e.,
downstream of SWM facilities), trees may not be located within public drainage
easements. Understory plants should be located >5' from CL of public drainage
easements. Locating plants within a public drainage easement carries risks (plant
remove/loss). Please ref. deed of dedication of public drainage easement for
proscriptive language. Review areas circled in blue, below.
On Sheets L3.10, L3.20 and L3.30 civil storm lines have been added as light linework with
easement boundary shown as well. Al trees have been moved out of public drainage
easements. All understory plants are located >5' from CL of public drainage easement.
2. Please consider and respond to VSMP/WPO Amendment review comments, d. 15 Jan
2020. Note: A closer reading of 17-603.C., and definition of water -dependent facility
(17-205) indicates that storm sewer is authorized in a stream buffer, meaning: 1)
mitigation of stream buffer impact associated with storm pipe is not required, and 2)
storm pipe may be located within the 50-streamward feet of a stream buffer. Please
disregard 15 Jan 2020 Engineering plan review comment 7, which does not accurately
state requirements.
Water -dependent facility. The term "water -dependent facility" means a development
that cannot exist outside of the stream buffer and must be located on the shoreline
ENGINEERING I DESIGN I TECHNOLOGY
because of the intrinsic nature of its operation and which include, but are not limited to:
(i) the intake and outfall structures of power plants, sewage treatment plants, water
treatment plants, and storm sewers; (ii) public water -oriented recreation areas; and (iii)
boat docks and ramps.
Outfall has been revised to ensure that pipe and riprap are contained within the first 50' of
the buffer.
3. C6.2, LD-347: Please review inlets 118, 120, 122, 126. Check pipe dia. v. outlet water
surface elevation and revise to ensure non -pressurized flow within capacity of pipe.
(Increase pipe diameter, as needed.)
Pipes have been revised to ensure non -pressurized flow.
4. C6.6: Show existing public drainage and SWM facility easements. Provide label ref. to
deed bk.-pg., Ex. Amendment, and plat at deed bk.-pg. 5198/669-670). Note: storm lines
below SWM facilities require a public drainage easement. Easement plat application.
Existing public drainage easements have been added.
5. Provide defined storm conveyance and typ. detail for ditch/swale on ease side of
downslope access to Spa. Proposed grading creates runoff conveyance at blue -circled
location, image below..
Grading has been revised to provide swale and new inlet have been added.
6. Recommend bypass for SWM3 should infrequent event overwhelm the underground
facility, or obstruction at weir plate prevents SWM3 design discharge via storm pipe
109. A possible option: locate a relief pipe that connects SWM3 with Str. 108; image,
below.
Acknowledged on proposed solution. The installation of a bypass impacts routing numbers
and overall water quantity measures. It is our preference to leave the system as proposed to
keep the overall system as efficient as possible.
7. C4.0: Revise 3' sidewalk to 5' width, Min.
Sidewalks have been revised to 5' minimum. Sidewalk from the eastern parking facility to the
building has been shown as 4' to match VSMP comment #6.
8. C0.0: Recommend title sheet include ref. to SDP2020-00002.
Reference number has been added.
We have included PDF copies of the plans and calculations for your review. If you have any
questions or comments, please feel free to give me a call at 434.295.5624.
Sincerely,
Andrew Allison, P.E.
Project Engineer