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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project:
Commonwealth Townhouses — SDP2010 -04 Major Amendment
Plan preparer:
Shimp Engineering, P.C. [434- 207 -8086]
Owner or rep.:
Moores Creek Land LLC
Plan received date:
20 Feb 2014
(Rev. 1)
8 Dec 2014
Date of comments:
8 Apr 2014
(Rev. 1)
8 Jan 2015
Reviewer:
Michelle Roberge
(Rev. 1)
John Anderson
Review Coordinator:
Sarah Baldwin
Engineering has completed the review of revised application SDP201400015 d. 12/1/14.
A. Site Development Plan (SDP201400015)
1) The site plan should not contain erosion control plans. Also, remove details pertaining to these plans. These
items will be reviewed with the WPO application. The title of the WPO plans should include "E &S and
Stormwater Management." (Rev. 1) Comment partially addressed. Title of WPO plans should include
"E &S and Stormwater Management." Please remove sheet C8B, Bioretention Details.
2) The critical slopes are considered "preserved slopes." Please label on plan. The critical slopes were
previously granted for disturbance. However, an improvement has to meet Albemarle County Code Section
30.7.5(1) and (2). The wall exceeds 6'. The wall should be broken into multiple stepped walls with a
maximum height of 6' and a 3' horizontal separation. Please address. (Rev. 1) Comment addressed.
3) All retaining walls require engineered plans (not generic manufacturer's detail and computation. (Rev. 1)
Comment not addressed — Applicant response (letter d. 12/1/14): "A structural engineer is reviewing the
proposed walls and shall provide us with specific design details." Furnish structural wall details for review.
4) Provide date of survey. All topography should be field verified by the designer within the last year. Please
verify site topography. (Rev. 1) Comment partially addressed. As follow -up, since topography field -
verified, revise contours to reflect sediment /debris elevation that obscures inlet of existing 48" DIA storm
line beneath Commonwealth Drive — WP0201400099 review comment Sec. C, #4 (1/8/15 comment letter).
5) Show detail of dumpster pad or note specification to be 4" stone base and 6" concrete of 3000 psi at 28
days, or stronger, reinforced with a minimum grid of wire reinforcing or #4 bars at 12" on center. (Rev. 1)
Comment addressed.
6) VDOT approval is required for the entrance intersecting Commonwealth Drive. (Rev. 1) As follow -up,
coordinate with VDOT on requirements relative to 48" storm line beneath Commonwealth Drive. Provide
design details accordingly — WP0201400099 review comment Sec. C, #6 (1/8/15 comment letter).
7) Proposed slopes steeper than 3:1 should have low maintenance (not grass) ground cover specified on plan.
Please provide. (Rev. 1) Comment partially addressed. As follow -up, revise note number 2, C6, to read:
"All proposed slopes greater than 3:1 shall have a low maintenance (not grass) ground cover. Contractor
shall determine the specific species at the time of planting, subject to County review and approval."
8) The site is proposed to drain into an existing 48" RCP pipe owned and maintained by VDOT. From there it
drains through the townhouse site, the Stonefield shopping center, under Rt. 29 and finally into the city.
Adequate channels are required to be demonstrated. The contributing drainage area, from your site, to a
point of discharge is one percent or less for the total watershed area. Please provide this analysis. Please be
aware that there have been great concerns at the discharge from Stonefield, and this site contributes to that
Engineering Review Comments
Page 2 of 2
flow directly. Also, verify capacity of the existing 48" pipe since it has been relined with another pipe.
(Rev. 1) Comment partially addressed under WPO201400099. As follow -up, WPO201400099
hydrologic report (cover letter 12/1/14) includes these statements: "Enclosed are the calculations and details
relating to stormwater quantity and quality for the proposed office at Commonwealth Office. This design
fulfills the requirements of Virginia Regulation 4VAC52 -60 -66 [renumbered as 9VAC25- 870 -661 Section
B 1 a by releasing the 2 -yr 24 -hr peak flow of 1.66 cfs at 14 fps to a concrete culvert, and Section C2b by
discharging to a point that currently experiences localized flooding, summarized in the following table..."
WPO reviewer failed to note need to demonstrate compliance with 9VAC25- 870- 66.B4. Applicant should
address intial Major Amendment review comments (preceding) with revised WPO Application, especially
with respect to limits of (channel protection) analysis (9VAC25- 870- 66.B4).
9) There were plans to convert the NW area of the site to a regional pond, but we are not certain when this will
take place. The culvert inlet is in poor shape with ponding limits encroaching on the neighboring property.
The area of the culvert inlet is unsafe and will need proper maintenance to remove excessive mud and
debris. The endwall may need to be replaced. This area should be cleaned and stabilized. (Rev. 1)
Comment not addressed under WPO201400099. Applicant should address intial Major Amendment
review comments (preceding) with revised WPO Application —see WPO201400099 review comments, Sec.
C, #5, 6; Sec. D, #10 (1/8/15 comment letter).
10) Change the configuration of the filterra inlet and grate inlet at the entrance to provide more runoff into the
filterra box. Also, to avoid the sump grate inlet at the main entrance, remove one parking space next to the
handicap parking and revise to a curb island. (Rev. 1) Comment addressed, Filterra relocated —see
WPO201400099.
Sincerely,
John Anderson
File: SDP201400015- Commonwealth Townhouse FMJ 010815rev