HomeMy WebLinkAboutWPO201200032 Review Comments Stormwater Management Plan 2012-05-17i"
,. `IRGINZP
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:
Plan preparer:
Owner or rep.:
Plan received date:
Date of comments:
Reviewer:
Review coordinator:
Riverfront Townhomes
1MSWIIKIZIZIx�
Dominion Engineering [fax 434 - 979 -16811
South Pantops H Land Trust; Charles [fax unknown]
W. Hurt & Shirle Fisher Trs
16 March 2012
17 May 2012
Michael Koslow
Megan Yaniglos
The first erosion and sediment control plan and stormwater management plan (WPO201200032)
submitted 16 March 2012 have received Engineering Review and do not appear to meet Albemarle
County minimum checklist items for approval. Please adequately address the following comments
for final approval:
Stormwater Management Plan
1) No stormwater treatment facilities appear in the plan as designed. These are required to capture, to
the maximum extent possible, the runoff from the entire land development project area [17-
312.C]. Recommend including filterra systems for Structure #6 and Structure #3. Note that a
Removal Rate for a project is calculated for each drainage area from the project at it's outlet
location (the proposed junction of the paved flume at the end of pipe #1 and pipe #4) [A.C. Design
Standards Manual Page 61.
Stormwater Management Comps
Erosion and Sediment Control Plan
1) Proposed sediment trap will not work as intended by applicant. Sediment traps, along with other
perimeter controls intended to trap sediment, shall be constructed as a first step in any land -
disturbing activity and shall be made functional before upslope land disturbance takes place
[VESCH p. III -71].
2) The County acknowledges the Rivanna River is an adequate outfall for runoff from this
development. However, a site visit indicated the channel from the 48" RCP to the Rivanna River
has already experienced severe erosion. Proposed rock cross vane and J -Hook Rock Vane as
shown on sheet SP I and SP 13 do not provide enough protection against erosion in this channel.
Alternate designs could include enclosing the drainage to the tow of the slope, creating a properly
lined adequate concrete channel with energy dissipaters, or creating a properly sized adequate
riprap lined channel with riprap check dams.
3) Once erosion mitigation measures have been determined, a corps permit will be required for
approval of this ESC plan as indicated on sheet SP11. Please provide this permit at the
appropriate time for approval of this ESC plan.
Engineering Review Comments
Page 2 of 2
4) Please update General Construction Notes for Erosion and Sediment Control Plans on sheet SP13
with the latest County notes from the Design Standards Manual.
5) Please indicate proposed staging and contractor parking areas or a statement if these areas will be
within the proposed limits of disturbance.
6) Please include dust control symbol within the limits of disturbance shown on sheet SP11.
Current Development Engineering is available from 2:30 -4 PM on Thursdays to discuss these review
comments. Please contact Michael Koslow at 434 - 296 -5832 ext. 3297 or email mkoslow @albemarle.org
to schedule an appointment.
[17- 204.f1 An application for an erosion and sediment control plan that requires modifications, terms, or conditions to be
included in order for it to be approved shall be deemed to be withdrawn if the owner fails to submit a revised plan addressing the
omitted modifications, terms or conditions within six (6) months after the owner is informed of the omitted information as
provided under paragraph (B).