HomeMy WebLinkAboutSUB200800138 Review Comments Road Plan and Comps. 2010-11-03ALg�,��
�'IRGINZ�
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: WPO- 2010 - 00062, Westhall V Construction Set
Plan preparer: Mr. David Jensen, PE; W & W Associates
Owner or rep.: Shiflett Farm, LLC
Date received: 3 September 2010 (application received 21 September 2010)
Date of Comment: 3 November 2010
Engineer: Phil Custer
The Construction Set (ESC, SWM, and Road Plans) for Westhall V, received on 21 September 2010, has
been reviewed. The WPO plan for this property has expired due to inactivity and a new application
number was assigned to this project. The previous ESC, SWM, and Road Plans were reviewed under
WPO- 2008 - 00038. The ESC and SWM plans will now be reviewed under WPO- 2010 - 00062. The road
plan will be tracked using the final plat application, SUB - 2008 - 00138.
A. Road Plan comments (SUB- 2008 - 00138)
1. The applicant has provided an approval email from Joel Denunzio at VDOT dated 26 September
2008. I have forwarded a copy of the latest submittal to Joel and am awaiting confirmation of
approval. Please note that the ditch work within the VDOT ROW is a new element to this plan
and must be approved by Joel as well.
2. A road bond must be posted prior to final plat approval. To request a road bond estimate, please
complete the request form and submit it to the county with a $250 fee. Before posting the road
bond, a schedule of completion must be approved by the County Engineer.
B. Stormwater Management Plan Comments (WPO- 2010 - 00062)
1. The pro -rata contribution for Westhall V has been computed to be $9,788.63. If this payment has
not be posted prior to the Board of Supervisors modifying the rate early next year, a new amount
will need to be calculated that may be more expensive.
2. Stormwater facility C has been verified to have met the requirements for the development of
Westhall V. When TMP 56 -53 is developed however, the owner will need to verify the adequacy
of the pond at that time.
3. A Stormwater facility maintenance agreement will be needed for each parcel with a stormwater
facility. Please submit this document to Ana Kilmer after reviewing the guidelines online. The
agreement should reference the current WPO plan, WPO- 2010 - 00062.
4. The SWM portion of the WPO bond will be computed at the time of plan approval.
C. Erosion and Sediment Control Plan Comments WPO- 2010 -00062
1. This submittal shows the offsite work on Park Road covered in Proffer 1.3. Though Current
Development Engineering review may approve the proposed plan, the proffer will remain
unaddressed until the County Engineer is satisfied with the construction. For this offsite work,
please make the following changes to DP -5:
a. Please show and calculate the limits of disturbance. The ESC narrative should be updated
considering this disturbance as well.
b. Show culvert inlet protection where applicable.
c. Show Permanent Seeding throughout the plan.
d. Please define the property lines more boldly. If work outside of the ROW is necessary,
construction easements will be required.
e. Please provide calculations showing that the new channels will be non - erosive for the 2-
year storm and with carry the 10 -year storm within its banks.
f. I recommend using riprap, concrete, or a similar material for channel SCC -1 because it
appears that the establishment of grass in this location will be difficult.
2. The adequate channel calculations must be updated to satisfy the requirements detailed in pages V-
122 through V -141 of the VESCH. The cross - section should be irregular and taken from a field
survey. I walked these downstream channels earlier this week and had difficulty locating cross -
sections E -E, F -F, and G -G. Each segment of each channel cross - section should have a computed
n -value (Table 5 -16 to 5 -21), permissible velocity (Table 5 -22), and computed velocity. Since
these channels are natural, only the 2 -year storm must be analyzed for erosion and capacity.
As an alternative to providing an analysis on the channel between the forebay and pond, the
applicant may provide a pipe instead. This would require an additional easement from the
downstream property owner. If this alternative is chosen by the applicant, I recommend designing
the outlet structure from the forebay in a manner that allows a minimal amount of water into the
existing channel to keep the wetland area alive, though this is not a requirement.
3. The county has updated the General Construction Notes for ESC plans since this plan was
prepared. Please modify the general notes to match the latest list from the Design Manual.
4. Please provide the county with all of the state and federal permits within the streams and wetlands.
5. All offsite easements must be recorded prior to issuance of a grading permit.
6. The ESC portion of the WPO bond will be computed at the time of plan approval.
File: El_rp esc swm_PBC_WPO- 2010 -00062 Westhall V Construction Set.doc