HomeMy WebLinkAboutWPO200800089 Review Comments Erosion Control Plan 2008-10-22� OF AL
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: Whittington Subdivision — Phase A
Mass Grading Erosion & Sediment Control Plan [WP02008000891
Plan preparer: Justin Shimp, DDR, LLC Ushimp @ddrva.com]
Owner or rep.: Justin Mallory, Whittington, LLC Umallory @stonehaus.com]
Plan received date: 29 Aug 2008
Date of comments: 22 Oct 2008
Reviewer: Amy Pflaum, Current Development Engineering
The Erosion & Sediment Control plan for Mass Grading of the Whittington Subdivision — Phase A,
submitted on 29 August 2008, has been reviewed. The plans cannot be approved as submitted and will
require the following changes /corrections prior to final approval.
General Plan Comments
1. Although this is not a plat, the lot layout shown on this plan does not appear to satisfy the
requirement of Proffer 6 of ZMA200600011. The boundaries of Lots 55 & 56 encroach into the
area that would be dedicated for future ROW of State Route 631.
2. This plan appears to be changing the concept plan for stormwater management. The ZMA plan
shows two ponds. The grading plan shows basins above the pond sites. Since the intent now
appears to be not to build the ponds or the rain gardens, please designate the locations of
permanent stormwater management features.
3. The building sites in Lots 5, 6, & 57 should be adjusted to minimize disturbance to the 100 foot
stream buffer. The decision regarding the vesting of this plan included the following advice from
the County Attorney's Office. "The new buffers should be complied with to the extent possible
where there is no interference with the vested plan. For example, if a house can be constructed on
Lot 6 without encroaching into the new stream buffer, the house should be constructed outside of
the stream buffer." It appears that Lots 5 -11 could be adjusted so that Lots 5 &6 could be pulled
farther out of the stream buffer, retaining as much of the stream buffer as possible in open space.
Erosion Control Plan
4. Proffers 4g and 4h from ZMA200600011 are not being satisfied with this plan. These proffers
must be satisfied or a waiver to disturb Critical Slopes must be approved by the Planning
Commission.
5. Please designate Critical Slopes areas on the Erosion Plan. Revise the hatching on the Critical
Slopes Plan so that it is more clearly identified.
6. Please show the existing driveways to the existing structures on TMP's 90 -3A, 90- 3BPlease
identify the staging and parking area on the plan
7. A temporary slope drain may be appropriate in Lot 58 to prevent discharge over disturbed slopes.
8. The Diversion proposed in Lot 57 should be located to capture run -off below the proposed grading
and convey it to Sediment Basin 3.
9. The proposed grading appears to create an un- drained low -spot in Lot 51.
10. Some lots contain spot elevations that do not correspond to the proposed grading.
11. There appears to be a natural drainage Swale to the west of Lot 44. If flow collects in this, does it
Albemarle County Community Development
Engineering Review Comments
Page 2 of 2
wash over Lot 44?
12. Please provide adequate channels to carry flow from Culverts A & B to Sediment Basin 1 and
Culvert E to Sediment Basin 3.
13. Sediment Basin 1 appears to be outfalling to an existing low -spot. Please direct the outfall to the
stream rather than the neighboring property.
14. Please provide floatation computations for the riser anchor size. The base dimension should be 2d
of the riser pipe.
15. Please recalculate the dewatering orifice size using the discharge equation for a vertical orifice in
the VESCH.
16. "Super Site Fence ", listed in the legend on Sheet 2, is not a DCR approved Erosion and Sediment
Control practice, please refer to Silt Fence with Wire Reinforcement.
17. An E &S bond amount will be computed by the County once the plans have been approved.
County Engineer Comments
18. The grading shown for lot 2 appears to be more than anticipated in the ZMA plan, and in an area
close to Old Lynchburg Road.
19. The road layout appears to be changing in the area of lot 50, and it is not clear how the road
continuation will work.
20. The overlot grading plan is not provided. Each individual lot area appears to be graded only
minimally. These will need re- grading by builders to work, raising issues with regard to driveway
placement, unresolved lot -to -lot drainage, and other concerns proffer 4 attempts to address.
Proffer 4 also appears to anticipate all of the development to be graded at once, rather than the
phased approach the grading plan provides.
Once these comments have been addressed, please submit 4 copies of the revised plans and reports to
Current Development Engineering.
Current Development Engineering is available from 2:30 -4 PM on Thursdays to discuss these review
comments. Please contact Amy Pflaum at 434 - 296 -5832 ext. 3069 or email apflaum @albemarle.org to
schedule an appointment.
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