HomeMy WebLinkAboutSDP201000035 Review Comments Preliminary Site Plan 2010-05-18*-&A
County of Albemarle
Department of Community Development
Memorandum
To: Gerald Gatobu, Current Development Project Planner
From: Phil Custer, Current Development engineering review
Date: 18 May 2010
Subject: West Village Preliminary Site Plan (SDP- 2010 - 00035)
The preliminary site plan for the West Village has been reviewed. The following comments are provided:
1. The 100 -year floodplain should correspond to FEMA flood elevations within the study. The flood
elevations shown within the study are to the North American Vertical Datum 1988 (NAVD 1988)
and the site survey is said to have used the National Geodetic Vertical Datum 1929 (NGVD 1929).
The site survey should be converted to NAVD 1988 to match the datum of the floodplain study.
(For further information, please refer to the FEMA website.) Additionally, the floodplain limits
should be revised as necessary to relate the elevations within the study to the site topography. In
other words, at the locations shown on the FEMA study, match the 675, 680, 686, and 693
elevations to the contour lines of the site - specific survey and interpolate where appropriate.
2. This site is located within the watershed of the County maintained Lickinghole Creek SWM
facility. Per Board policy, all development within this watershed must pay a pro -rata fee in
exchange for the water quality treatment provided by the facility. The West Village project is not
required to provide SWM quality onsite and County Engineering will not be reviewing the future
WPO application for water quality requirement. The pro -rata fee will computed at the time of
final site plan approval.
3. The only stormwater management requirements to be reviewed for this project will be detention of
the 2 and 10 year storms to pre - development rates. This will be reviewed with the WPO
application in conjunction with final site plan. Additionally, because of the considerable size of
the watershed to Powell's Creek (- 2450acres) relative to the site (- 20acres), the County will likely
look favorably upon a detention waiver if requested by the applicant per 17- 314.G.
4. If the ESC plan is not phased considerably, I see no alternative for the ESC plan other than a basin
located within the 100 -year floodplain, which would require a Special Use Permit. I recommend
revising the layout of development to locate a stormwater detention facility out of the floodplain
and to make sure it is large enough to provide the proper ESC volume during construction.
Otherwise, a sediment basin will be needed in the southeastern corner of the site and will likely
consume much of the developable area of block 4.
5. This site generates more than 200 VPD and doubles the volume of traffic currently experienced by
the existing road (Blue Ridge Avenue ADT 330). Therefore, the project requires a Traffic Impact
Analysis (Chapter 527) before approval.
6. There is a considerable amount of vacant land northwest of this property. Once this land is
developed to its full potential as currently zoned and a public road connection is made to Cling
Lane, it is likely that the ADT for West Village Avenue will be greater than 2000 vehicles a day.
The ADT would be higher if the Master Plan densities were used. Therefore, the road should be
designed for an ADT greater than 2000 vehicles a day unless otherwise approved by VDOT.
7. Please show the construction of West Village Drive to the property line of TMP 56A1- 01 -31. [14-
409.B] The requirement may be waived by the agent. At this time, I do support the waiving of
this requirement.
8. Please show the sight distance triangles for each entrance onto West Village Avenue. For the
Current Development
Engineering Review Comments
Page 2 of 2
entrance closest to the end of the street show the sight triangle to the north on the existing platted
ROW.
9. The swale will not work with the street trees in place. Please either request that the agent waive
the street tree requirements in this area or remove the Swale and replace with the standard 6ft
planting strip.
10. The Water Quality Swale within the VDOT ROW will require the county to enter into an
agreement with VDOT to assure its maintenance. The County will subsequently be required to
enter into an agreement with the property owner to assure the swale's maintenance by the
Homeowners association. I have some concerns with the current design, but because this BMP is
not needed for county SWM requirements, the issue can be addressed during the final review of
the plan.
11. The Stream Buffer for this section of the county is 100ft from the edge of bank or the limits of the
100 -year floodplain, whichever is greater.
12. If a retaining wall is needed adjacent to the intersection of West Village Ave. and Blue Ridge
Ave., a guardrail will be required. This guardrail must be within the VDOT ROW. Please show
the guardrail on the plan and adjust property boundaries and setbacks accordingly. I recommend
removing the need for a retaining wall by providing a 3:1 slope to existing grade.
13. The first entrance onto West Village Drive may be too steep and need to be revised during the
final site plan. [ 18- 4.12.17]
14. The permeable paving will be reviewed during the final site plan stage once the section has been
determined. However, pavers will likely need to be removed from all entrances onto the State
ROW.
Pile: E1_psp_PBC_sdp201000035 Wcst Villagc.doc