HomeMy WebLinkAboutWPO201800013 Correspondence WPO VSMP 2018-06-12BOHLER ENGINEERING
28 Blackwell Park Lane, Suite 201, Warrenton, VA 20186
Professional Engineering Services Telephone: (540) 349-4500 Fax: (540) 349-0321
LETTER OF TRANSMITTAL
VIA: FTP Upload
TO: Albemarle County
Community Development
401 McIntire Road
Charlottesville, VA 22902
(434) 296-5832
ATTN: Emily Cox, P.E.
RE: WP0201800013
Virginia Stormwater Management Plan for Road
Improvement Plan Phase 1 — 2nd Submission
Brookhill Development
Route 29 (Seminole Trail Road) and State Route
643 (Polo Grounds Road)
Charlottesville, VA 22902
Albemarle County
DATE: June 12, 2018
JOB NO: V152000
WE ARE SENDING YOU ❑ Shop drawings ❑ Copy of letter ®Attached ❑ Prints ❑ Change order
COPIES JOB# DATE REVISION REVISION SHEET NO. DESCRIPTION
DATE
1 V152000 1-2 of 2 Virginia Stormwater Management
Program (VSMP) Application for
Albemarle County
1 V152000 1-5 of 5 Comment Response Letter
1 V152000 12/15/17 1-23 of 23 Virginia Stormwater Management
Plan
These Are Transmitted: ❑ For approval ❑For your use ❑As requested
❑ For review and comment ❑Approved as submitted ❑Approved as noted
❑ Returned for corrections
REMARKS:
Enclosed please find the above mentioned items for the Brookhill Development project in Charlottesville, VA.
Should you have any questions or require additional information, please do not hesitate to contact this office at
(540) 349-4500.
COPY TO: SIGNED:
17P, 8�r
Ryan Yauger, P.E.
File
TM
BOHLER
E N G I N E E R I N G
Albemarle County
Department of Community Development
401 Mchitire Road, Room 227
Charlottesville, VA 22902-4596
(434) 296-5832
Attn: Emily Cox
Dear Ms. Cox:
28 Blackwell Park Lane, Suite 201
Warrenton, VA 20186
PHONE 540.349.4500
June 12, 2018
Via Federal Express
Re: WP0201800013
Virginia Stormwater Management Plan
for Road Improvement Plan (Phase 1) —
1' Submission Responses
Brookhill Development
Route 29 (Seminole Trail Road) and
State Route 643 (Polo Grounds Road)
City of Charlottesville
BE #V 152000
Bohler Engineering is pleased to submit on behalf of Riverbend Development, hic., the 2nd Submission
for the Virginia Stormwater Management Plan for Road hmprovement Plan (Phase 1). The following is
our comment response letter addressing comments received from your department. Each comment is
addressed and responded to as follows:
C. Stormwater Management Plan (SWMP)
Comment 1: [General] Topo must be field verified by designer within the past year. Please provide
most recent date of field verification.
Response 1: The topography shown in the plan is a combination of the topography provided by
Lincoln Surveying, Bell Land Surveys, and Roudabush Gale, and the proposed
grading shown in WPO 201700037. No construction activity has taken place to date.
Last site visit was held on 6/1/18.
Comment 2: [General] Show preserved and managed slopes.
Response 2: The preserved and managed slopes areas have been added to the plan and a hatch
legend has been added to the differentiating the two has been added to the
applicable plan sheets.
Comment 3: [General] Provide greater contrast/differentiation between approved "existing"
topography and proposed grading for current plan.
Response 3: The line separating the approved/existing topography has been updated and
additional labeling has been added to all sheets where shown.
Comment 4: [General] Identify and label all SWM facility easements.
Response 4: All SWM easements have been labeled.
CIVIL AND CONSULTING ENGINEERS • PROJECT MANAGERS • SURVEYORS • ENVIRONMENTAL CONSULTANTS • LANDSCAPE ARCHITECTS
WWW.BOHLERENGINEERING.COM
B O H L E R Bobby Jocz
E N G I N E E R I N G Brookhill Development
Virginia Stormwater Management Plan for
Road Improvement Plan (Phase 1) 1st Review Comments
June 12, 2018
Page 2 of 5
Comment 5: [General] Due to changes in pond riser design for ponds 10 and 11, provide updated
SWM stage/storage curves/routings etc. These maybe provided in separate calculations
booklet or electronic submittal.
Response 5: An updated SWM report with revised routings will be submitted under a separate
cover.
Comment 6: [C-106] Ensure all items from the approved ZMA and Stormwater Master Plan are
accurately shown throughout the entire plan. It appears the extent of the stream buffers
shown on sheet C-106 do not match that as shown on the approved ZMA.
Response 6: The stream buffers shown in the plans are based on the buffers shown in the plan
titled "Wetlands & Waters of the U.S. Impact Map Brookhill" dated: 7/6/16 last
revised on 2/20/17. A note has been added to sheet C-106.
Comment 7: [C-202] Provide dimensions for level spreaders (Length). Ensure easement around
structure is labeled.
Response 7: The level spreaders are now detailed, including dimensions on sheet C-909. The
easement has also been labeled please see sheet C-202.
Comment 8: [C-203] Drainage label area B32 is repeated. Please correct.
Response 8: The repeated label has been revised to B31 to note the correct structure. Please see
sheet C-203.
Comment 9: [C-900] Drainage areas do not match those shown on approved plan WP0201700037
sheet C-901 (predevelopment drainage map). Please correct/explain inconsistencies.
Remove proposed stormsewer layer from pre -development drainage area map.
Response 9: The total drainage to POI-11 is the same in both plans. In WP0201700037 the
drainage area was broken up to differentiate the areas that were not located within
the LOD.
Comment 10: [C-900] Pre -development curve number for POI-10 inconsistent between what is
presented in stormwater narrative and energy balance table on sheet C-901. Please
correct.
Response 10: We have reviewed and did not find any of the inconsistencies noted above. However,
all the drainage areas have been updated with this revision and have been checked
to ensure that they are consistent throughout the plan.
Comment 11: [C-900] Provide note that for WPO calculations conditions pre -development drainage
areas are presented as exist prior to land disturbance approved in WP0201700037.
Response 11: A note to this effect has been added to sheet C-900.
Comment 12: [C-901 ] Drainage area callouts missing for: area of pond 10 (if being consistent with
pond 11), and area south of Untreated DA (To POI-11) encompassing portions of Route
29.
Response 12: Callouts for these drainage areas have been added to the plan. Please see sheet C-
901.
CIVIL AND CONSULTING ENGINEERS • PROJECT MANAGERS • SURVEYORS • ENVIRONMENTAL CONSULTANTS • LANDSCAPE ARCHITECTS
WWW.BOHLERENGINEERING.COM
®BO H L E R Bobby Jocz
E N G I N E E R I N G Brookhill Development
Virginia Stormwater Management Plan for
Road Improvement Plan (Phase 1) 1It Review Comments
June 12, 2018
Page 3 of 5
Comment 13: [C-903] VRRM spreadsheet analysis for Drainage Area-D includes more than just the
ROW area. 6.13 acres are indicated as included in this DA where 5.02 acres are shown
for ROW area on sheet C-901. Please clarify/correct.
Response 13: The drainage area was incorrect and has been revised to 5.07 in both the VRRM
and the post developed drainage area sheet. The additional 1.11 acres in the VRRM
is for the open space to pond 11. Please see sheets C-901 and C-904.
Comment 14: [C-904] Provide phosphorous removal achieved with proposed plan for Pond 10. Update
Plan #s.
Response 14: The achieved phosphorus removal has been added. Please see sheet C-904.
Comment 15: [C-905] Check Stormwater outfall table for correct figures. The POI-10 CN for the post
development lyr storm is listed to be 82. In previous sections (energy balance table) this
is identified to be 68. Please correct/clarify.
Response 15: The stormwater outfall tables and the Energy Balance Calculations have been
revised to reflect the correct CN. Please see sheets C-901 and C-905.
Comment 16: [C-905] Culvert reports should note related POI. In addition, the culvert report for POI-
11 incorrectly references the involved structures. It should state culvert A40-Al as shown
on the drainage area maps.
Response 16: The culvert reports have been added as requested. Please see sheet C-905.
Comment 17: [C-905] Please clarify what "10 Year Storm Calculations" table is referencing. Points do
not correlate to any identified structures/points.
Response 17: These Calculations are for the outfall of pond 11 and are provided to show that the
10-year storm event is adequately conveyed through the system to the existing onsite
channel. This table has been moved to sheet C-907 and relabeled for clarity.
Comment 18: [C-905] Provide culvert calculations for all proposed culverts along Polo Grounds Road.
Response 18: Culvert computations for all culverts along Polo Grounds have been added. Please
see sheet C-905.
Comment 19: [C-905] Level spreader design inadequate. Grading does not appear to be sufficient for
continued spread down length of spreader. Design has potential for clogging/high
maintenance requirements. Please re-evaluate design.
Response 19: The level spreader design has been revised to provide an adequate ditch section
behind the rigid lip to allow for proper dispersion of water and to prevent clogging.
See revised detail on sheet C-909.
Comment 20: [C-906] For the pond 10 profile, ensure label arrows correctly lineup to features they
identify.
Response 20: The Labels for pond 10 have been revised to more clearly identify what features
they are highlighting.
Comment 21: [C-906] Length and slope of outfall pipe as indicated differs between plan, profile, and
riser detail. Please correct.
Response 21: The length of the outfall pipe has been revised to match. Please see sheet C-906.
CIVIL AND CONSULTING ENGINEERS • PROJECT MANAGERS • SURVEYORS • ENVIRONMENTAL CONSULTANTS • LANDSCAPE ARCHITECTS
WWW.BOHLERENGINEERING.COM
®BO H L E R Bobby Jocz
E N G I N E E R I N G Brookhill Development
Virginia Stormwater Management Plan for
Road Improvement Plan (Phase 1) 1It Review Comments
June 12, 2018
Page 4 of 5
Comment 22: [C-907] Length of outfall pipe as indicated differs between plan, profile, and riser detail.
In addition, profile view presents conflicting values for the 1 and 100yr WSEs.
Response 22: The 100-yr WSE has been updated and the Pond Profile and riser detail have been
revised to match. Please see sheet C-907.
Comment 23: [C-905 & C-906] Identify changes made to pond area and/or riser structures from
previously approved plans. Profile views should identify changes by showing updated
structures/grading in pre -constructed condition (bold with no opacity). A note should be
provided outlining additional changes.
Response 23: A note has been added to sheets C-906 and C-907 to highlight the changes made to
the riser structure made with this plan.
Comment 24: [C-905 & C-906] Since changes are being made to riser structures and additional
information is provided for drainage areas, provide updated "APO Conditions" and
structure anti -floatation calculations tables for Ponds 10 and 11.
Response 24: Anti -flotation Calculations for the revised riser structures have been provided.
Please see sheet C-908.
Comment 25: [C-908] Confirm trash rack design conforms to VDOT standards.
Response 25: The proposed trash rack meets the VDOT standards.
D. Erosion and Sediment Control Plan (ESOP)
Comment 1: [General] provide outlet protection designs for all outlet protection locations.
Response 1: An outlet protection design table has been added. Please see sheet C-206.
Comment 2: [General] Label stormwater management ponds and level spreaders.
Response 2: The SWM ponds and level spreaders have been labeled. Please see sheets C-202, C-
906, and C-907.
Comment 3: [General] Ensure labels for E&S measures do not obscure drainage area/inlet labels.
Response 3: The labels for the E&S measures have been relocated so they do not obscure the
drainage area/inlet labels.
Comment 4: [General] Ensure all existing E&S measures previously installed under WP0201700037
that are meant to remain through this phase are shown on plans (i.e. Wetland
protection/tree protection fencing, etc.). Provide shading/labeling to indicate that these
are existing measures.
Response 4: The E&S measures that are to remain in place from WP0201700037 have been
added to the plan with a label stating that they were installed with WP020170037.
Comment 5: [General] Show proposed construction entrance, washout, and staging area locations.
Response 5: the construction entrances, washouts, and staging areas have been added to the plan
as requested. Please see sheets C-X200 and C-202.
CIVIL AND CONSULTING ENGINEERS • PROJECT MANAGERS • SURVEYORS • ENVIRONMENTAL CONSULTANTS • LANDSCAPE ARCHITECTS
WWW.BOHLERENGINEERING.COM
B O H L E RM Bobby Jocz
E N G I N E E R I N G Brookhill Development
Virginia Stormwater Management Plan for
Road Improvement Plan (Phase 1) 1It Review Comments
June 12, 2018
Page 5 of 5
Comment 6: [C-200] Adjacent to the planned intersection of Route-29 and Road -A, re -grade
depression where culvert inlet is located in previously approved WP0201700037.
Unwanted ponding may occur. Ensure positive drainage to new culvert inlet location.
Response 6: The grading around the culvert has been revised. Please see sheet C-200.
Comment 7: [C-201 ] It appears the orientation of the construction road servicing pond 11 changes
From what is presented in phase 111 WP0201700037. Please detail this change.
Response 7: A note directing the contractor to relocate the access road as shown has been added
to the plan.
Comment 8: [C-202] Show/callout salamander crossings.
Response 8: The salamander crossing callout has been added. Please see sheet C-202.
Comment 9: [C-206] Provide manufactures detail for Gutter buddy. Variance will be need for DEQ
approval.
Response 9: The Gutter Buddy detail is shown on sheet C-206. Please consider this comment
response as our request for a variance for DEQ approval.
Should you have any questions regarding this project or require additional information, please do not
hesitate to contact me at (540) 349-4500.
Sincerely,
Bohler Engineering, VA LLC
Yzrw--,
Ryan Yauger, P.E.
RY/ib
HAI5\V152000\Administrative\Letters\Road Plan WP0\l80612 Road Plan WPO 1st Review CRL.doc
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