HomeMy WebLinkAboutWPO200700082 Review Comments Erosion Control Plan 2009-08-19� 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: Ashcroft West ESC Plan [WP0200700082]
Plan preparer: Neal Wright; Dominion Engineering
Owner or rep.: Pantops - Lakeridge LLC
Plan received date: 14 July 2009
Date of comments: 19 August 2009
Reviewer: Phil Custer
The Erosion and Sediment Control Plan for Ashcroft West, submitted on 14 July 2009, has been reviewed.
The previous plan set had been given approval by engineering review in February of 2008, but since the
owner had not acted on the plan after 6 months of approval it became subject to re- review per 17- 208.3.
The following comments must be addressed before approval of the set is given:
Adequate channel concerns have not been addressed with the addition of the level spreaders, as
proposed, at the basin outlets. The discharges these facilities will be subject to are too high and
will likely lead to reconcentration of the water immediately downhill of the facility and,
consequentially, long -term erosion. In addition, the VESCH also stipulates that the area
downstream should not be greater than 10%. To address the adequate channel issue, engineering
recommends that the facilities be modified to reduce the outlet flows of the 2 and 10 -year storms
as much as possible. For each facility, I managed to keep 10 -year flows under lcfs while keeping
the same geometry by using a flow limiting inlet.
Embankment spillways should be properly lined. Please specify the dimension and lining of the
spillway for each facility.
There are also adequate channel concerns at the ditch outlets for the section of the new road.
Erosion appears to be an issue before and after the old sediment trap across from Lego Dr.
2. Sediment trap 4 needs to be relocated to an area where it can capture construction activity.
3. ESC measures are needed on the east side of the road at Sta. 19 +00. A sediment trap appears to be
the most appropriate measure to be located there.
4. Staging and construction areas do not appear to be protected by ESC measures at Sta. 14 +00 and
34 +00.
5. Please extend the silt fence on the west side of the road from Sta. 16 +50 to 18 +50 to more
adequately protect the area below the road embankment.
6. Please show the grading and design of the ditches from the two cul -de -sacs down to the
stormwater facilities. Please specify the dimension and lining of the ditches and detail how these
ditches will cross the access roads to reach the facilities.
7. A variance has been given by the program authority for the height of the sediment traps given the
steep topography.
EI csc PBC /Ashcroft West ESC Plan.doc