HomeMy WebLinkAboutWPO202000019 Review Comments WPO VSMP 2020-04-24COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
VSMP Permit Plan Review
Project: Chattanooga — Colonnade Drive - VSMP
Project file#: WP0202000016
Plan preparer: Jonathan Showalter, PE, Timmons Group — 608 Preston Ave, Suite 200,
Charlottesville, VA 22903 [ jonathan.showalter(&timmons.com ]
Owner or rep.: John Thier, Turner Enterprise, 250 W. Main St.
Charlottesville, VA 22902 [ johnAturner-enterprises.com ]
[ jpierceLbeclubva.org ]
Plan received date: 30 Mar 2020
Date of comments: 24 Apr 2020
Reviewer: John Anderson
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 for reasons listed 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 ESOP, (3) a SWMP, and (4) any TMDL measures necessary.
1. Sec. 1, Registration Statement is incomplete.
Complete Sec. 1 as condition of VSMP /WPO plan approval.
a. Sec. IV.E. list `Albemarle County' since project is in county MS4.
b. Sec. IV.G. Revise HUC to 020802040401.
c. Sec. VI. Sign Certification (print /sign /date).
2. Sec. 4, 5: Update these sections with revised ESC and SWM plan sheets, once comments are addressed.
3. Sec. 6.A. / Exhibit: Indicate location rain gauge.
4. Sec. 9.: SIGNED CERTIFICAT10N —sign certification (delete what appears to be extraneous ref. to Mr. Joseph
P. Letteri).
5. Revise SWPPP title to include ref. to VSMP /WP02020-00019.
B. Pollution Prevention Plan (PPP) — See above.
The PPP content requirements can be found in County Code section 17-404.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This
plan is disapproved for reasons listed below. The stormwater management plan content requirements can be
found in County Code section 17-403.
C3.3
1. Label all retaining walls along edges of site. Assign unique identifiers (Wall A, B, C, etc.) to each wall.
2. Provide lintel detail for detention outfall pipe where it passes beneath retaining wall at east corner of site.
3. Label SWM detention system outfall public drainage easement.
Engineering Review Comments
Page 2 of 4
4. Note: Easement plat must be recorded prior to VSMP Approval.
* SWM Facility, public drainage, and sight distance easements
5. Note: VSMP approval is required prior to final site plan approval.
6. Wherever proposed parking lot grade concentrates runoff against a curb, provide CG-6. [18-4.12.15.g.]
C4.0
7. Revise sheet title to site layout. A VSMP /WPO Plan cannot approve a site plan.
8. Retaining walls > 4-ft. require sealed professional geotechnical design. Since proposed retaining wall
supports parking infrastructure, provide detailed geotechnical retaining wall design to Engineering for
review prior to VSMP /WPO plan approval.
9. Mill and overlay 25' (minimum) either side of site entrance, full lane width of Colonnade Drive, NBL.
10. If existing pavement is alligatored or in bad repair, then more than 25' full lane width mill and overlay will
be required. Engineering intends to evaluate existing Colonnade Drive, NBL, via site visit.
C5.0
11. Ensure Structures 204, 203, 202, and 201 work with segmental block retaining wall geogrid, if geogrid is
required.
12. Provide a French drain (or similar collection system, similar to Boys & Girls Club) to collect /screen runoff
from dumpster area to prevent runoff crossing entire paved parking lot area between dumpster and Str. 204.
13. Show 72" CMP storage pipe (detention system) manway access, located in parking lot.
14. Break pipe 103 into two sections (provide MH) so that pipe in public drainage easement only passes
beneath one of two tiered retaining walls. Albemarle typically does not allow pipes in public drainage
easements to pass through or beneath walls.
15. Retaining Wall Note 4. (revise `Albemarle')
16. Provide cross -sectional trapezoidal, V-shaped, or other channel x-section, with riprap detail (Str. 102).
17. Provide velocity2_yr calculation for Q2_yr at Str. 102 (discharge to riprap channel).
18. C5.2: Label existing contours.
19. C5.3: Provide and record sight distance easements, left -right, for areas outside Colonnade Drive 62' right-
of-way. Show and label sight distance easements on site plan (SDP2020-00030), proposed sight distance
easements on WPO202000019 C5.3.
C6.0
20. Provide post -developed impervious cover table listing building, parking, walks, etc., to match Design
Calculations & Narrative report, p. 27, New development VaRRM.xls, 0.61 Ac. impervious cover.
21. Water quality analysis: Revise statement to read `Required removal will be achieved through purchasing
1.09 lb. of offsite nutrient credits.'
22. Provide 1" =20' scale plan view of CMP storage pipe system.
23. Provide detailed Mfr. guidance /specifications /recommendations for installation, periodic inspection, and
maintenance of the underground detention system, similar to information provided for Lane Manufacturing
detention system proposed for Boys & Girls Club (Timmons Group).
24. Provide 1" =10' plan and profile drawings of structure housing weir plate. Provide details sufficient for
plan review, installation, construction inspection, DEQ or other agency inspection, and bond release.
25. Provide trash /debris rack details for 12" and 16" DIA orifices. Include weir plate mounting details.
C7.0
26. Label inlet structure upstream of storm pipe 405.
27. Provide invert elev. of pipe 301 at 72" CMP storage pipe.
28. Cutaway image of 72" CMP storage pipe is insufficient detail for underground detention system; provide:
a. Full profile view, labeling
i. Elevations of
1. Pipe bedding
2. 72" pipe invert
3. 72" pipe crown
4. Slope (%)
Engineering Review Comments
Page 3 of 4
5. Pipe 201 invert Elev. at 72" storage pipe (detention system)
ii. Minimum depth of cover above storage pipe
iii. Weir plate elevations (Also, item 22, above)
b. Label system dimensions
i. Overall length
ii. Total length of system pipes
iii. Overall width
iv. Storage pipe diameter
v. Provide easement width sufficient for installation, or replacement. See easement width
diagram at ACDSM, p. 15 /image, below
Albemarle County Design Standards Manual — Engineering 0-
LA5L%1LNTR1DYH. DIAMETER T-2.H V,«LT W}II\,i
29. Revise SWPPP and Calculation booklet covers to include reference to WPO202000019.
Calc. booklet
30. LD-204, Str. 204: Revise height of curb opening, units =FT.
31. Revise d/h (Str. 204): FT/FT (should be < 1.0)
32. Provide 1-, 2-, 10-yr storm elevations within the detention system. If available at HydroCAD routings,
please advise where. Engineering prefers to check against weir plate details, C6.0.
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 disapproved for reasons listed, below. The erosion control plan content requirements can be found in
County Code section 17-402.
1. C1.3: Provide VDOT 2016 Road and Bridge Standard WP-2 detail on civil sheet.
2. C2.0, C2.1, C3.2, C3.3: Compare with GIS. Confirm extent of critical slopes shown on plans match GIS.
3. C3.1: Include paved wash rack detail, ACDSM, p. 8
C3.2
4. Provide stone ramp in Colonnade Drive if curb /gutter remain once work begins. C2.1 appears to indicate
portion of curb and gutter demolished (ESC, Phase I). If so, C3.2 should depict curb and gutter removed.
5. Label retaining wall (and max. ht.) at pipe culvert.
6. Revise entrance symbol to PCE
7. Revise silt fence along NW LOD to run with contours, not cross -contour.
8. Revise label `Contractor to provide silt fence, filter sock, or approved equivalent,' to read `Contractor to
Engineering Review Comments
Page 4 of 4
provide silt fence, or approved equivalent: may include filter sock, if approved'. Also applies to C3.3.
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.
Process:
After approval, plans will have 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 have to be completed by the owner and submitted along with cash,
certificates or sureties for the amounts specified. The agreements will have 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.
Stormwater Management Facilities Maintenance agreements will also have 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 have to be submitted along with court recording fees.
After bonding and agreements are complete, county staff will 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 have 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. [DEQ permit NA since LOD < 1.0 Ac., z 0.85 Ac.]
After Maintenance Agreement and easement plat are recorded, the County can hold a pre -construction conference.
Applicants must 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 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;
hLtp://www.albemarle.org/deptfonns.asp?department--cdengmTo
WP0202000019_Chattanooga_Colonnade Drive 042420