HomeMy WebLinkAboutWPO201800084 Review Comments WPO VSMP 2019-04-03Al
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Project title:
Project file number:
Plan preparer:
Owner or rep.:
Plan received date:
Plan received date:
Date of comments:
Date of comments:
Reviewer:
VSMP Permit Plan Review
Royal Fern Phase 2
WP0201800084
Shimp Engineering, Justin Shimp, P.E.
justin@shimp-engineering.com
Land Striker, LLC
15 November 2018
18 March 2019 (Rev. 2)
29 November 2018
03 April 2019 (Rev. 2)
WW Associates, Inc.
County Code section 17-410 and Virginia Code §62.1-44.15:34 requires the VSMP authority to
act on any VSMP permit by issuing a project approval or denial. This project is denied. The
rationale is given in the comments below. The VSMP application content requirements can be
found in County Code section 17-401.
A. Stormwater Pollution Prevention Plan (SWPPP)
The SWPPP content requirements can be found in County Code section 17-405. A SWPPP must
contain (1) a PPP, (2) an ESCP, (3) a SWMP, and (4) any TMDL measures necessary.
1. The SWPPP was not found with this submittal. Please provide SWPPP.
Rev. 1 Comments
1. SWPP Section 2 — Please provide a copy of the DEQ coverage letter when obtained.
Rev. 2: Noted
2. SWPP Section 8 — Please provide name of qualified person and other requested
information.
Rev. 2: Noted
3. SWPP Section 10 — Per 9VAC25-880-70 Part K, please provide the person with the
authority to sign inspection reports or to modify the stormwater pollution prevention
plan.
Rev. 2: Noted
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. The PPP exhibit will need to be included in the SWPPP.
Rev. 1: Comment addressed.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a
SWMP. This plan is disapproved, and the reasons are provided in the comments below. The
Engineering Review Comments
Page 2 of 6
stormwater management plan content requirements can be found in County Code section 17-403.
1. The 3.18 lbs/yr of nutrient credits will need to be purchased prior to plan approval. Please contact
Ana Kilmer before purchasing the credits.
Rev. 1: Comment will need to be addressed prior to plan approval.
Rev 2: Plan has been revised and comment is no longer applicable.
2. Please provide a signed and dated engineers seal on the calculations package.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Rev. 2: Comment addressed.
3. Show existing storm sewer pipe below the point of analysis at Wahoo Way.
Rev. 1: Comment addressed.
4. Provide calculations to demonstrate adequacy of existing storm sewer pipe below the point of
analysis at Wahoo Way.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Rev. 2: Please provide pipe calculations demonstrating the adequacy of the existing
downstream storm sewer pipe to convey the runoff from the proposed development. The
cover sheet statement provided does not address the capacity of the downstream storm
sewer in the as -built condition.
5. Please add the Albemarle County General Construction Notes for Stormwater Management Plans.
Rev. 1: Comment addressed.
6. Please show time of concentration flow paths on all drainage area maps.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Rev. 2: Comment addressed.
7. Provide time of concentration calculations as part of the calculations package.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Rev. 2: Comment addressed.
8. Provide pretreatment at the outfalls of all pipes prior to discharging to biofilters.
Rev. 1: Comment addressed.
9. Provide underdrains in all the proposed biofilters.
Rev. 1: Comment addressed.
10. Biofilter underdrains shall have a minimum diameter of 6" in accordance with DEQ stormwater
design specification No. 9.
Rev. 1: Comment addressed.
11. Please show the biofilter underdrains in the plan view to ensure that they do not conflict with the
proposed landscaping.
Rev. 1: Comment addressed.
12. Please label the proposed biofilter landscaping in the plan views.
Rev. 1: Comment addressed.
13. Please label the stormwater maintenance easements on the proposed biofilters and underground
detention.
Rev. 1: Comment not addressed. Labels have been provided for the proposed utilities. Please
label the stormwater maintenance easements on the proposed biofilters and underground
detention.
Rev 2: Plan has been revised and comment is no longer applicable.
14. A Stormwater Maintenance Facility Agreement must be recorded for the proposed biofilters prior
to plan approval.
Rev. 1: Comment will need to be addressed prior to plan approval.
Rev 2: Plan has been revised and comment is no longer applicable
15. The calculations for Ditch 9 indicate an allowable velocity of 4.00 ft/sec for the specified lining
but show a calculated velocity of 4.15 ft/sec. Please update the calculations.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Engineering Review Comments
Page 3 of 6
Rev. 2: Comment addressed.
16. Please provide calculations showing adequacy of downstream pond on Cavalier Crossing
property (TMP 76-54A1).
Rev. 2: See additional comments below.
17. Please note that additional comments may be generated based on the response to the comments
provided.
18. Revise wet pond label, sheet C7, which reads:
"Approved with SDP200100129 and expanded with SDP201500043. The wet pond was
designed to treat 60.26 Ac. + 11.18 Ac. the original drainage area (60.26 Ac.) includes the Royal
Fern Phase 2 site and was assumed to have an overall developed land cover of 63% impervious."
—to include reference to specific sheets of approved design plans (or calculation report) for
recently -modified wet pond shown in multiple plats, plans, and WPOs over the past twenty -plus
years. This note (C7) is inadequate from a review perspective. Additional file research maybe
required.
(Notel: SDPs rarely approve SWM Plans. Although stormwater management features may
appear on site plans in general (and limited specific) detail, an approved Site Plan rarely approves
stormwater management design required for development. WPO plans are means of review
/approval of SWM facility design, an important distinction.)
(Note2: SDP200100129 does not include any plan sheet showing "western residue of the
Heischman property." Cover letter d. 3/12/19 explains information listed in the approved
calculation packet for SDP200100129 is relevant. Please provide this information with revised
VSMP /WP0201800084). Transfer images to plans.)
(Note3: SDP201500043 shows approved site grading, but does not include design expansion of
Ex. wet pond to accommodate Fifth Street Place development. Ref. WPO201500094, link,
below.)
19. VSMP Plan must reference WPO201500094 plan and profile revised volume, final embankment
elevation/s, shoreline contours, routings, etc., since wet pond was modified with Fifth Street Place
development.
( It is fair to ask why, if pond was initially designed (per C7 wet pond label, item 1, above) to
receive and treat runoff from a 60.26 Ac. watershed, constructive modification was required with
Fifth Street Place development.)
20. VSMP /WPO201800084 must show existing SWM wet pond contours. That is, Fifth Street Place
post -developed condition. Existing condition is current As -built condition, which differs from
Fifth St. Place pre -development.
21. Engineering cannot approve VSMP /WPO201800084 on basis recorded deeds or past design
without thorough and specific consideration of pond in current As -built condition, and estimate of
watershed impervious area that routes to it.
22. Current wet pond configuration may provide capacity adequate as required per Part IIC criteria,
but since pond has been modified, principal design task is to compare and contrast As -built wet
pond to current watershed impervious area that drains to it.
23. During 2-28 meeting, Shimp Engineering offered to provide (mixed graphic /CAD approach)
supportive exhibit estimate of impervious area. Please provide exhibit.
24. Engineering cannot assume 63% impervious watershed but needs to examine, as nearly as
possible, current watershed impervious area /exhibit. Please estimate current watershed
impervious area that drains to the wet pond.
25. Design needs to furnish information not included with 3/13/19 submittal. Please provide images,
references, calculations, As -built information.
Engineering Review Comments
Page 4 of 6
Link to SDP200100129 (plan and calculations):
http://www.albemarle. org/weblink/search.aspx?dbid=3 &searchcommand=%7b%5bCDD-
Planning%5 d: %SbApplicationNumber%5 d=%22 SDP200100129%22%7d
From SDP200100129 /title sheet:
MAX. INPERWOUS COVER: x,80 AO,
6MDNGSa t,aa A0.
PARKING, SIDEWALKS. TRAVELWAM $As AC_
Engineering requests Shimp examine Approved WPO Plan, especially SWM-series of sheets and include
relevant information required for accurate computational evaluation of Royal Fern Phase 2 site runoff, if
routed to pond of revised design, and As -built condition, as discussed 2/28/19.Include images.
Goal: Provide basis for Engineering evaluation of whether current existing As -built condition of the wet
pond revised with Fifth Street Place development is adequate to accept and treat Royal Fern Phase 2 post -
developed site runoff, under technical criteria Part IIC. As -built condition and current watershed
impervious area are key.
D. Erosion and Sediment Control Plan (ESCP)
Virginia Code §62.1-44.15:55 requires the VESCP authority to approve or disapprove an ESCP.
This plan is approved.
1. Please add WP0201800084 to the cover sheet of the plans, calculations, and SWPPP.
Rev. 1: Comment partially addressed. No calculations package provided with resubmittal.
Rev. 2: Comment addressed.
2. Please provide a signed and dated engineers seal on the calculations package.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Rev. 2: Comment addressed.
3. A VDOT Land Use Permit will be required prior to construction for the work shown within the
VDOT right-of-way along State Route 780 (Old Lynchburg Road) and State Route 631 (5'
Street).
Rev. 1: Comment noted by applicant.
4. A temporary construction easement will be required prior to plan approval for the work shown on
the adjacent property along Wahoo Way.
Rev. 1: Comment addressed.
5. Provide culvert inlet protection on the existing 36" storm at the intersection of Wahoo Way and
5' Street during "Perimeter Controls" phase to protect downstream storm sewer system prior to
construction of new storm sewer.
Rev. 1: Comment addressed.
6. Provide outlet protection for the sediment basin outfall pipe.
Rev. 1: Comment addressed.
7. Please add a soil stockpile location to the plans.
Rev. 1: Comment addressed.
8. Please provide Contractor's staging and parking areas.
Rev. 1: Comment addressed.
9. Provide a drainage area map for the proposed sediment trap and basin.
Engineering Review Comments
Page 5 of 6
Rev. 1: Comment addressed.
10. Please show time of concentration flow paths on all drainage area maps.
Rev. 1: Comment not addressed. No calculations package provided with resubmittal.
Rev. 2: Comment addressed.
11. Provide time of concentration calculations as part of the calculations package.
Rev. 1: Comment not addressed. Provide time of concentration calculations for the sediment
basin as part of the calculations package provided with resubmittal.
Rev. 2: Comment addressed.
12. Identify the party responsible for land disturbance on the plans.
Rev. 1: Comment addressed.
13. Provide calculations to verify that the 2:1 length:width flow path ratio requirement is met for the
proposed sediment trap.
Rev. 1: Comment addressed.
14. Please note that additional comments may be generated based on the response to the comments
provided.
The VSMP permit application and all plans may be resubmitted for approval when all comments have
been satisfactorily addressed. For re -submittals please provide 2 copies of the complete permit package
with a completed application form.
Engineering plan review staff are available from 2-4 PM on Thursdays, should you require a meeting to
discuss this review.
Process:
After approval, plans will need to be bonded. The bonding process is begun by submitting a bond
estimate request form and fee to the Department of Community Development. One of the plan reviewers
will prepare estimates and check parcel and easement information based on the approved plans. The
County's Management Analyst will prepare bond agreement forms, which will need to be completed by
the owner and submitted along with cash, certificates or sureties for the amounts specified. The
agreements will need to be approved and signed by the County Attorney and County Engineer. This may
take 2-4 weeks to obtain all the correct signatures and forms.
Please coordinate nutrient credit purchase with the County's Management Analysis prior to purchase.
Evidence of a purchase of necessary nutrient credit is required prior to applicant receiving a grading
permit.
Stormwater Management Facilities Maintenance agreements will also need to be completed and recorded.
The County's Management Analyst or other staff will prepare the forms and check for ownership and
signature information. The completed forms will need to be submitted along with court recording fees.
After bonding and agreements are complete, county staff will need to enter project information in a DEQ
database for state application processing. DEQ will review the application information based on local
VSMP authority approval. At this time, the DEQ portion of the application fees will need to be paid
directly to the state. For fastest processing, this is done electronically with the emails provided on the
application. DEQ should notify applicants with instructions on how to pay fees. When DEQ approves the
application, they will issue a permit coverage letter. This should be copied to the county.
After DEQ coverage is issued, via the coverage letter, the County can hold a pre -construction conference.
Applicants will need to complete the request for a pre -construction conference form, and pay the
remainder of the application fee. The form identifies the contractor and responsible land disturber, and the
fee remaining to be paid. This will be checked by county staff, and upon approval, a pre -construction
Engineering Review Comments
Page 6 of 6
conference will be scheduled with the County inspector. At the pre -construction conference, should
everything proceed satisfactorily, a joint VSMP and grading permit will be issued by the County so that
work may begin.
County forms can be found on the county website forms center under engineering;
hllp://www.albemarle.orp-/deptforms.asp?department=cdengno
File: WPO201800084 Royal Fern Phase 2 11-27-18.doex