HomeMy WebLinkAboutWPO202000034 Correspondence 2020-08-26® ROUDABUSH, GALE & ASSOCIATES, INC.
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August 26, 2020
Mr. David James
Department of Community Development
401 McIntire Road
Charlottesville, VA 22902
Project title: Belvedere Phase 5A
Project file number: WPO-2020-00034
Dear David,
The plans have been revised to include the second stage of construction. It has been
determined that it would simplify the approach since the parcel will only have one VSMP permit.
The second stage of construction proposes 19 single family dwellings for which a Road Plan will
be submitted in the future.
Please find attached the revised plans. The plans have been revised to address the comments
in accordance with the comments received on the VSMP Permit Plan review.
A. General
1. Cover — add "WP0202000034" under the title.
Response: Project file number has been added to the cover sheet.
B. Stormwater Pollution Prevention Plan (SWPPP)
2. Registration statement:
a. Add 'County of Albemarle' under Section IV. E.
b. Sign & date.
Response: County of Albemarle has been added to page 2 of the registration statement. A
revised Registration statement is included with this submission. If another hardcopy of the entire
SWPPP notebook is required, please contact our office.
3. Please update the plan insert sheets with the approved plan sheets once
approved, prior to pre -construction meeting.
Response: The approved plan sheets will be added to the SWPPP notebook once we have
received approval from the County.
4. Provide & complete items of the SWPPP:
a. Section 8 — Qualified personnel prior to pre -con.
b. Section 9 — Signed Certification prior to approval.
Response: Section 8 and 9 are included with this submission. If another hardcopy submission of
the full SWPPP notebook is required, please contact our office.
5. SWM Pond: Add a forebay.
Response: A forebay has been added.
C. Pollution Prevention Plan (PPP)
6. Update the PPP.
Response: An updated PPP is included with this submission.
D. Stormwater management Plan (SWMP)
7. Sheet 13: Please address Water Quantity requirements, Part II B for those areas
in your limits of disturbance that are not being accounted for Post -Development.
Response: The area behind the lots will be graded/seeded/landscaped as necessary to fully
stabilize the site. The roof drains will catch the water and discharge towards the street. The site
will not have any concentrated flow at the rear of the lots. Downstream properties will not be
adversely affected.
8. Provide 10' (min) SWM facility access easement. The access will need to be
paved if the grade is over 20%.
Response: The easement has been showed to match the easement plat. Access has been
graded in accordingly to provide less than 10% slope throughout. The access easement,
stormwater management easement, and temporary grading and construction easement have all
been shown on sheets 9,10, and 11.
9. Show easement over SWM facility.
Response: The easement has been shown to match the easement plat. The access easement,
stormwater management easement, and temporary grading and construction easement have all
been shown on sheet 9,10, and 11.
10. Sheet 14: Please verify the DA to proposed culvert is correct. Where does the
area in red drain?
Response: The drainage area for the culvert has been updated. The culvert calculations have
been updated to reflect the changes to the drainage area.
11. Please address the runoff & Water Quantity requirements for the access road
area.
Response: The temporary portion of the that connects to Belvedere Blvd will eventually become
a designed/paved road. Water quantity for that portion will be captured with a stormwater pipe
network, designed, and submitted with the Future Phase 4 plans. The portion of the road
leaving Phase 5, and extending over the Future Phase 3 Block 10A development will be
temporary. Eventually this road will connect to Farrow Circle as depicted on the Phase 3 Block
10A Initial Site plan submitted on August 10, 2020. The entire section of the road will be built
and stabilized as soon as possible. There is no anticipated concentrated flow leaving which
would require water quantity. Since the first submission of the VSMP, additional field survey was
completed, and the existing sediment basin behind lot 245 is shown. During construction of the
secondary access road, the existing basin will be used to serve as an erosion control measure.
12. Pond:
a. Provide a sediment forebay. Follow the erosion & flood control guidelines
from VADEQ, Appx. D.
b. Provide a trash rack for riser low -flow orifice. Orifices under 3" dia. are
susceptible to clogging. Increase size or install a non -clogging orifice
design. Show detail.
Response: A sediment forebay has been added to the design. A 1" x 1" rectangular orifice
satisfies the 1yr EB requirement. Wire mesh has been specified to be installed over the orifice to
prevent clogging and shown on the plans.
13. Calculations:
a. Please use the precipitation data from NOAA Atlas 14. Based upon the
site's location these are the values below.
Response: Plans have been revised to reflect NOAA Atlas 14 data and analyzed as such for the
Charlottesville location.
14. Contact Ana Kilmer if you wish to move forward with the Nutrient Credit
purchase. Currently, 4.57 Ib/yr TP credit needed.
Response: Ana Kilmer has been contacted regarding nutrient purchase upon plan approval. The
nutrient credits required has changed since the first submission. 8.29 pounds are required.
15. Record the SWM maintenance agreement.
Response: Ana will need to prepare the agreement prior to recordation.
E. Erosion and Sediment Control Plan
16. Sheet 3: ST-1 & ST-2 do not meet the maximum embankment height of 5'. 1
measure a height of 10' & 6' respectively.
Response: It has been determined that two sediment traps can be removed since the basin
provides sufficient capacity for the area per the design guidelines. Diversions have been added
to Phase 1 to direct the water to the basin.
17. Sheet 4: You should have diversion going to a ST here.
Response: Given that the background has been updated with the new field topo - it is not
feasible to add a sediment trap at this portion of the plan. The existing basin will be utilized for
erosion control during the construction of the fire road. Outlet protection will be use at the outfall
of the culvert to ensure the bank is protected.
18. Sheet 6: Add BM and MU here.
Response: The BM and MU labels have been added to the requested areas on the plan.
19. Sheet 10:
a. Need to also size the S.B. structures for the pre -development or
intermediate phases of construction.
Response: The S.B. is sized to handle the largest quantity of water at any stage of construction.
b. You state that the S.B is designed to handle Belvedere 513. You would
have to submit an E&SC plan for 5B.
Response: The S.B is sized large enough to meet the anticipated capacity of the future
development of the site. The E&SC plan for 5B is shown on this submittal.
20. Indicate the slopes 3:1 or greater where low -maintenance ground cover is
req u i red.
Response: The labels have been added to the slopes.
21. Provide OP shape & stone size calcs (see VADEQ ESC HB Spec. 3.18). Extend
outfall protection to the bottom of pond.
Response: Please see below for OP at the outfall of the basin and culvert.
oP#1
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We thank you for taking the time to review these plans and trust the above adequately
addresses your comments. However, please let me know if you have any questions or require
additional information.
Very truly yours,
Riki Van-Niekerk