HomeMy WebLinkAboutSDP200800081 Review Comments Minor Amendment 2009-03-30� 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: J.W. Townsend Landscaping Improvements — Minor Amendment
[SDP200800081 ]
Plan preparer: Jim Taggart, TCS Engineering [fax 361 -1216]
Owner or rep.: J.W. Townsend [email jay @townsendlandscape.com]
Plan received date: 4 June 2008
Rev, 1:
Rev,2:
Date of comments:
Rev, l :
Rev,2:
Reviewer:
Rev.l &2 :
25 August 2008
11 March 2009
22 July 2008
09 October 2008
30 March. 2009
Amy Pflaum, Current Development Review Engineer
John Diez , Current Development Engineering Technician
Minor Site Plan Amendment Comments
1. Easements or letters of intent are required for off -site work. It appears that temporary grading and
construction easements will be necessary from TMP's 32 -6A and 32 -22B1. Please submit
easement documents for all new easements or demonstrate that these easements are not necessary.
(Rev. 1) Comment has not been addressed.
(Rev. 2) Comment has not been addressed.
2. All slopes steeper than 3:1 will require non - grassed low maintenance ground cover, please specify
with a note on the plan. [DM]
(Rev. 1) Comment has been addressed.
In the Albemarle County Development Area, curbing is required on all parking areas and
travelways with VDOT designations (CG -2, CG -6).
(Rev. 1) Comment has not been addressed. If you do not wish to add curb, then please submit a
waiver request as per section 18.4.12.2.c.2.
(Rev. 2) Comment has been addressed. This item was waived by the Department of Current
Development.
4. Although labeled as 8.25% on the plan, the portion of the proposed travelway uphill of the two
new parking areas is graded at 20 %. Travelways should not exceed a 10% grade.
(Rev. 1) Comment has not been addressed. There still seems to be grades that exceed 10% on
the travelway.
(Rev. 2) Comment has been addressed.
Albemarle County Community Development
Engineering Review Comments
Page 2 of 5
A guardrail with VDOT designations (GR -2, GR -2a, etc.) is required next to parking or travelways
adjacent to retaining walls or drop -offs of greater than 4 feet, with start and end sections labeled.
[18- 32.7.2]
(Rev. 1) Comment has not been addressed.
(Rev. 2) Comment has not been addressed. Bumper blocks are needed on the parking spaces
southeast of the relocated shed. Guardrails are required where there is a 2:1 slope. For
example, adjacent to the southwest corner of the lower parking lot and adjacent to the
travelway leading up to the lower parking lot. An alternative to guardrails is to provide 3:1
slopes adjacent to the parking or travelways.
6. An Erosion & Sediment Control Plan and Stormwater Management Plan are required. Please
submit along with a Water Protection Ordinance application. Comments #7 -16 will need to be
addressed with the WPO.
(Rev. 1) Comment has been addressed.
7. Please remove all Erosion & Sediment Control features on the Site Plan.
(Rev. 1) Comment has been addressed.
Location of the retaining wall is not clear. Please provide start and end elevations for the retaining
wall, as well as elevation marks throughout the wall.
(Rev. 2) Comment has been addressed.
9. Please provide retaining wall details referenced from the plans. A typical manufacturers drawing
for segmented block walls, or VDOT reference, is acceptable, with any applicable safety railings
or guardrail shown.
(Rev. 2) Comment has been addressed.
10. Small scale of plan makes it difficult to determine dimensions of parking and loading spaces.
(Rev. 2) Comment has been addressed.
Stormwater Management Plan Comments
i'lease mits of th ge area to the proposed stormwater management pond and sub-
areas to the culverts.
(Rev. 1) Comment has been addressed.
12. Please provide culvert computations for the two proposed culverts under the travelway.
(Rev. 1) Comment has been addressed.
13. Please provide a cross section detail of the proposed pond.
(Rev. 1) Comment has been addressed.
14. The pond is sized as a detention facility, but no outlet structure is shown. Please provide details
and sizing calculations for the outlet structure.
(Rev. 1) Comment has been addressed.
Albemarle County Community Development
Engineering Review Comments
Page 3 of 5
15. Please address the stormwater management of the concentrated run -off from the proposed pond.
Identify the adequate channel from this site. It appears a drainage easement may be needed from
TMP 32 -22B 1.
(Rev. 1) Comment has not been addressed. Concentrated run -off from the proposed pond has
not been addressed. Concentrated run -off appears to be flowing to the neighboring property.
Please identify the adequate channel from this site. Also, please provide a drainage easement
from TMP 32 -22B1.
(Rev. 2) Comment has not been addressed. Please provide an adequate channel analysis
meeting all requirements from the County's Design Manual.
16. A stormwater management easement is required around the proposed swale and pond and any
associated structures.
(Rev. 1) Comment has not been addressed. The easement must be extended to the property line
by Rte. 29.
(Rev. 2) Comment has been addressed. A stormwater management easement does not have to
be extended to the property line. We see that the ACSA easement will suffice.
17. Please provide for vehicle access to the proposed pond. Access must be graded to 10' width and
less than 20% grade, gravel surface or better is required for grades over 10 %. Please provide a
minimum 10' wide permanent easement over the access.
(Rev. 1) Comment has been addressed.
18. A Stormwater Management bond amount will be computed by the County once the WPO plans
have been approved. A completed copy of the standard stormwater management maintenance
agreement and fee for recordation for any stormwater management facilities will be required. [17-
304E]
(Rev. 2) Comment has not been addressed.
19. Please submit a completed copy of the standard Stormwater Maintenance Agreement and fee for
recordation for the proposed stormwater management facilities.
(Rev. 2) Comment has not been addressed.
20. Please provide all existing easements with deed book references, locations and dimensions.
[18- 32.6.6, 14 -3021
(Rev. 1) Comment has been addressed.
21. Please provide a detail of the proposed grassed swale per the VSMH (blue book) 3.13
(Rev. 2) Comment has not been addressed. Please remove the note on the plans if a swale is not
provided.
22. Please specify all dimensions on the outlet protection detail.
(Rev. 1) Comment can be discarded. We see the dimensions on the plans. But, for future
references, we suggest that dimensions be specified on all details if possible. Thank you.
23. Please include a detention summary table with pre - development and post - development rate
calculations.
(Rev. 2) Comment has been addressed
Albemarle County Community Development
Engineering Review Comments
Page 4 of 5
24. Please provide a float calculation for the pond riser structure.
(Rev. I) Comment has been addressed. We've reviewed the details once more and found it to
suffice due to the fact that the dimensions of the base are twice the size of the riser.
25. If the pond is to provide extended detention, please design per the VSMH (blue book) 3.07.
(Rev. 2) This plan does not provide water quality to state standards. As computed by the
applicant, the required removal rate for the project is 30%. The Virginia Stormwater
Management Handbook identifies several BMPs that provide this removal rate. For example,
Extended Detention Basins, Type I Retention Basins, and Water Quality Swales are all
accredited a 35% removal rate by the VSMH. It appears that the applicant has attempted to
design a retention basin for water quality treatment. Unfortunately, the minimum drainage
area for retention basins (as specified in the VSMH and included in Albemarle County's
Design Manual) is IO acres. The use of a retention basin in this location is not appropriate.
All of these items were discussed in the telephone conversation between Phil Custer and Mr.
Taggart.
It should be noted that no matter the BMP specified for this project, sediment forebays are
required. The removal rates attributed to most BMPS assume that an appropriately sized
sediment forebay is provided.
26. Please simplify post - development calculations so that there is one drainage area to the pond.
(Rev. 2) Comment has been addressed
27. Please specify water quality volume (WQV) method and counts.
(Rev. 2) Please see comment #25.
28. Please provide a plan view of the pond at a larger scale so that we may review the grading. Scale
should be F = 20' — 30'.
(Rev. 2) Comment has been addressed. However, the grading of the pond must be changed in
order to provide water quality treatment.
29. (Rev.2) Please provide an updated Routing Report after the basin is modified.
30. (Rev. 2) Please remove the note regarding future stormwater management review. When a future
site plan amendment is submitted, a stormwater management amendment will be required. Or, the
applicant will be required to prove adequacy of the constructed facility.
Erosion & Sediment Control Plan Comments
30. An Erosion & Sediment Control bond amount will be computed by the County once the WPO
plans have been approved.
31. Please include the acreage of disturbance in the project description of the narrative.
(Rev. I) Comment has been addressed
32. Is the proposed pond to serve as a sediment basin during construction? If so, please provide sizing
calculations and details per the VESCH 3.14
(Rev. 2) Comment has not been addressed. This facility must act as a Sediment Basin during
construction.
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Albemarle County Community Development
Engineering Review Comments
Page 5 of 5