HomeMy WebLinkAboutWPO201700056 Approval - County 2018-06-27
COUNTY 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 -Approved
Project: Springhill /Townplace Suites – VSMP
Project file number: WPO201700056
Plan preparer: Dominion Engineering (Note: purchased by Roudabush Gales Associates, 2018)
172 South Pantops Drive, Charlottesville, VA 22911 [dgreen@roudabush.com ]
Owner: STCVille Hotel, Inc,
Plan received date: 7/19/17
12/28/17 (Rev. 1)
2/27/18 (Rev. 2)
4/27/18 (Rev. 3)
6/11/18 - .PDF
6/20/18 - .PDF
6/22/18 - .PDF
6/25/18 (Final)
Date of comments: 8/23/17
1/26/18
3/29/18
5/25/18 (Rev. 3)
6/19/18 -email
6/21/18 -email
6/22/18 -email, ref. RMS docs
(Final) 6/27/18 –Approved
Reviewer: David James (ext. 3273) –thru Rev. 3
John Anderson – .PDF and Final
WPO2017-00056
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 Approved. The rationale is given in the
comments below. The application may be resubmitted for approval if all of the items below are satisfactorily
addressed. 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. (Rev.1) Registration Statement – Please check a box for number 10 on the form (yes or no).
(Rev.2) Addressed.
2. (Rev.1) Provide copy of DEQ coverage letter when obtained.
(Rev.2) Acknowledged.
3. (Rev.1) Provide a reduced size copy (11x17) of the ESC and SWM plans.
(Rev.2) Addressed.
Engineering review comments
Page 2 of 6
4. (Rev.1) Provide PPP exhibit sheet (11 x 17) of the site that shows the location/sources of pollutant(s),
and pollutant generating activities as outlined in Section 6.
(Rev.2) Addressed.
5. (Rev.1) Provide two (2) copies of the SWPPP; signed & sealed.
(Rev.2) Addressed.
6. (Rev.3) Submit (2) two updated copies of the SWPPP; signed & sealed.
(Rev.4) Addressed.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17 -404.
1. (Rev.1) Identify pollutant preventive and control measures to be used. Show controls on PPP and ESC plan
(Ref. 9VAC25-880-70, Part II).
(Rev.2) Update PPP with E&SC changes below.
(Rev.3) Please submit latest PPP for review; insert into SWPPP.
(Rev.4) Addressed.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is
approved (prior comments addressed).
1. (Rev.1) Add the WPO number to the title sheet.
(Rev.2) Addressed.
2. (Rev.1) The Permanent Detention & Drainage Easement recorded in DB 1705 Pg 112 does not include
the applicant as part of this agreement. Considering the County does not own this land, it cannot
grant rights of access on this parcel. An easement must be secured by the applicant and recorded
prior to approval of this application for any offsite activities not covered under an existing easement
agreement.
(Rev.2) Addressed.
3. Provide a SWM narrative. State how water quantity & quality requirements will be satisfied.
(Rev.2) Show channel protection requirement is meet to the limits of analysis, which is the location
where this site area is less than 1% of the total watershed area or the site peak flow rate for the 1-yr
storm event is less than or equal to 1.0% of the existing peak flow rate from the one -year 24-hour
storm prior to the implementation of any stormwater quantity control measures ) [9VAC25-870-
66.B.4]. Correct drawings and calculation package.
(Rev.3) Addressed.
4. (Rev.1) Sheet SW12/SW13 – Is the offsite DA 0.31 ac or 0.24 ac? Remove “Pre Developed…” label at
the bottom.
(Rev.2) Addressed.
5. On page 7 of the calcs, the “Generated Flow Inlet #3” should be #2 according to the plans.
(Rev.2) N/A.
6. Submit a maintenance agreement for SWM detention facility.
(Rev.2) Submit stormwater maintenance agreement before plan approval [17-415].
(Rev.3) Acknowledged. Agreement required prior to permit issuance.
(Rev.4) Addressed.
7. Submit a deed of dedication and SWM easement plat for the SWM facility. The SWM facility cannot be
within the parking deck.
(Rev.2) SWM easement deed/plat required before plan approval [Policy]. Storm easement must continue
through parking deck to outfall.
(Rev.3) SWM facility easement plat and deed must be submitted, reviewed, approved and recorded prior to
VSMP plan approval.
(Rev.4) Our records indicate it hasn’t been approved. Please submit the deed and plat for final
review. Plans cannot be approved until they are recorded.
Engineering review comments
Page 3 of 6
8. Show the lower parking deck, not the upper, and associated grading. The drive aisle into the lower deck
shall not exceed 16%.
(Rev.2) Refer to site plan comments – not a VSMP comment.
9. The retaining wall supporting entrance roadway and parking structure will need to have its design approved
before the WPO plans can be approved.
(Rev.2) Certify the wall design at each crossing where they meet or are located above storm pipes:
Str. 3 to 2, Str. 1B to 1, and Str. 10 to 10A. Show retaining wall in the profile where it crosses pipe
Str. 10 to 10A.
(Rev.3) Addressed; see site plan comment.
10. Provide maintenance requirements and schedule for the underground SWM facility.
(Rev.2) Addressed.
11. Provide construction details of underground detention facility (base, compaction, backfill
requirements, etc.).
(Rev.2) Addressed.
12. Areas of Forest/Open space to be protected as undisturbed space (outside limits of disturbance) &
shall be protected as such in agreements, deed of dedication, and platted within an easement.
(Rev.2) Addressed.
13. (Rev.1) Show that upstream structure (ST 3) from underground vault will not overflow for 100 -yr
storm.
(Rev.2) N/A; Drainage design revised.
14. Provide the maximum impervious area of the future development. Or will this be a ‘stand -alone’
project? Regardless, provide calculations showing stormwater system (pipes) will handle future
development without flooding.
(Rev.2) Addressed.
15. Please contact Ana Kilmer regarding nutrient credit agreement.
(Rev.2) 2.11 lb/yr TP load reduction required for site. Contact Ana Kilmer prior to purchasing credits.
Credits must be purchased prior to issuance of DEQ General Permit and County land disturbance permit.
(Rev.3) 2.16 lb/yr nutrient credit to be purchased prior to permit being issued.
(Rev.4) The agreement has been sent to the county attorney’s office for review.
16. Remove signature block from cover sheet.
(Rev.2) Addressed.
17. (Rev.2) Provide a soils map and soils type information.
(Rev.3) Addressed.
18. (Rev.2) Sheet SW11 – Show “Trench” (drain?) (4A?). Verify drainage area. Provide design details.
Add to ‘storm inlet computations’ table.
(Rev.3) Addressed.
19. (Rev.2) Sheet SW9 – Show profile and cross section for riprap ditch/channel over STR-1 to EW. Include
slope & lining information, max flowrate & velocity for sizing of riprap. Indicate size of riprap. How will
drainage flow over EW without causing erosion?
(Rev.3) Check outfall design with Frank – SW9
(Rev.4) Not addressed. Show design in accordance with Flexible Lining Channel (see VESCH, pg. V-
102)
20. (Rev.2) Sheet SW9 – 20-ft overflow weir detail – Will water pond 2.2-ft in the parking deck? If so,
provide calculations showing that the 50-yr storm event can pass through the grate assuming the
grate is 50% clogged to ensure vehicles are not flooded.
(Rev.3) Addressed.
21. (Rev.2) Sheet S11 – Parking deck drainage is not clear. How is upper level drainage being handled? Verify
drainage area is correct. Add insert of upper level, similar to what was provided on the site plan. Lower
deck drains to STR-1B, which is then connected to STR1 – drainage area is incorrectly routed to STR1.
(Rev.3) Partially addressed. Add insert as stated on SW4/SW7. Provide detail of drainage design
from 1C to 1B.
(Rev.4) Acknowledged.
Engineering review comments
Page 4 of 6
22. (Rev.2) Provide routing calcs for all storm piping, structures, and detention pipes for the 2- and 10-yr storm
events. Confirm HGL is detained within structures and structures do not flood. Add 2 - and 10-yr stage
elevations for weirs.
(Rev.3) The routing calcs show 48”x48” orifices. Where are those shown in the pipe design? Ensure
sizes match what’s shown on plans. F4 has a slope of 2% according to plans & is different from
design calcs. Please indicate max discharge for the design storms (can be shown stage discharge
curves).
(Rev.4) Addressed.
23. (Rev.2) Show the DA going to the existing drainage inlet located near Seminole Trail (refer to aerial
below).
(Rev.3) Addressed.
24. (Rev.2) SW9 – Show section A-A line (with arrows) on 1/SW10 detail.
(Rev.3) Addressed.
25. (Rev.2) Correct the sheet/detail callouts for any drawings on the details sheets. For instance, details
on SW9 refer to SW10.
(Rev.3) Addressed.
26. (Rev.2) Calculations Packet:
a. Hydraflow analysis shows stage-storage detention for a box chamber/orifice design. Provide
for circular pipe/orifice design as shown on plans.
(Rev.3) Addressed.
b. Precipitation values of 3.68 (2-yr) & 5.55 (10-yr) are a little off versus NOAA values of 3.66
& 5.53 respectively. Please correct.
(Rev.3) Addressed.
c. It appears that the post-development DA#1 should have HSG D soils in addition to B soils.
Please confirm and provide routing calcs (pg. 8).
(Rev.3) Addressed.
d. Provide Tc calculation worksheet.
(Rev.3) Addressed.
27. (Rev.2) Move access MHs to just upstream of the weirs for all detention facilities.
(Rev.3) Addressed.
28. (Rev.2) Provide specific requirements for DI-1 structures as mentioned in the design detail notes (on
sheet SW6) for each structure shown on the profile sheet(s).
(Rev.3) Addressed.
29. (Rev.2) Provide DI-3A, 3B, 3C VDOT structure details & notes. Provide requirements for DI-3A, 3B,
3C structure, as mentioned in the design detail notes on profiles.
(Rev.3) Addressed.
30. (Rev.2) Provide DI-7, 7A, 7B VDOT structure details & notes. Provide requirements for DI-7, 7A, 7B
structure, as mentioned in the design detail notes on profiles.
(Rev.3) Addressed.
31. (Rev.2) Add storm pipe from 1 to EW to the ‘Storm Drain Computations” table on SW*. Confirm velocity
at outlet and provide outlet design (riprap sizing, dimensions, etc.). Provide detail for outfall EW at the
pond. This should be a VDOT standard EW. Outlet velocity shall not exceed 10 fps.
(Rev.3) Check outfall design with Frank – SW9
(Rev.4) Show design in accordance with Flexible Lining Channel (see VESCH, pg. V-102). Include
riprap channel and gabion basket in SWM maintenance narrative.
32. (Rev.2) Provide Nyloplast Grate design details & notes.
(Rev.3) Addressed.
33. (Rev.2) Provide anchor blocks for pipe slopes greater than 16% (every other pipe joint at a
minimum) and details.
(Rev.3) Addressed.
34. (Rev.2) Add bedding details, notes, installation, and inspection requirements for detention pipes.
(Rev.3) see SW9
Engineering review comments
Page 5 of 6
35. (Rev.2) Correct structure identifications in “Storm Drainage Computations” table on Sheet SW8.
(Rev.3) Addressed.
36. (Rev.2) Velocity in storm pipes shall not exceed 20 fps.
(Rev.3) Addressed.
37. (Rev.2) Will future development require a way to drain site underground? If so, consider extending a
stub-out to the site for future connection. Development of this area will required a VSMP
amendment.
(Rev.3) Acknowledged.
38. (Rev.3) SW7 – Label/ID the pipe connecting to Str.12.
(Rev.4) Addressed.
39. (Rev.3) SW12 – Change number for ‘Post Development Detained Area 1 (STR#1B)’ (should be 5).
(Rev.4) Addressed.
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 (prior comments addressed).
1. (Rev.1) Show extent arrow for TS/DC and callouts with leader/arrows. Please use a uniform size/scale for
text, lines, and symbols.
(Rev.2) Addressed.
2. (Rev.1) Sheet SW4
a. Adjust grading for DD path to allow for drainage.
b. ST-2 where grading of ST to be 6’ from property line [18-30.7.5(b)].
c. Provide at least 3-ft of undisturbed area between the property line and ST -1.
d. Remove SF from in front of the riprap outfall of ST-1 and extend riprap to the concrete channel.
(Rev.2) Addressed.
3. (Rev.1) Sheet SW5
a. Label/callout diversion dike. Grey-out the sediment trap and stone/riprap section so we can see the
storm structure and labeling.
b. Add SF along property line adjacent to proposed sidewalk (Route 29 & proposed road). Add
TS/PS to future development parcel.
c. Add SF on north property line along entrance aisle.
d. Add SF along ST-2; leave outlet open.
e. Adjust DD to drain positively (it cannot ‘run uphill’ and be expected to function properly).
(Rev.2) Addressed.
4. (Rev.1) SW6 – Add SF along back of proposed sidewalk & property line.
(Rev.2) Addressed.
5. (Rev.1) Fuel/Chemical storage to be 50’ (min) from any downstream drain inlets.
(Rev.2) Addressed.
6. (Rev.1) Include note in E&SC plan: Proposed slopes greater than 3:1 shall have low maintenance (not grass
or mulch) ground cover.
(Rev.2) Addressed.
7. (Rev.1) Provide impervious area for phase II area.
(Rev.2) Addressed.
8. Provide at least 2-ft of undisturbed area between the property line and disturbed areas where the sediment
trap is located.
9. (Rev.1) Show any staging, stockpile, and borrow areas (if there are any). These areas need ESC
protection/controls, including any offsite locations.
(Rev.2) Show SF around stockpile and add a concrete washout area, including a concrete
washout detail. Protect fuel/chemical storage areas.
(Rev.3) Partially addressed. Show concrete washout detail.
(Rev.4) Addressed.
10. (Rev.2) Show IP for existing inlets (see Comment #23 above).
Engineering review comments
Page 6 of 6
(Rev.3) Addressed.
11. (Rev.3) SW3 – Add an outlet at end of diversion (@ 461’), or continue div. to ST.
(Rev.4) Addressed.
12. (Rev.3) SW6 – Please update table in the diversion detail.
(Rev.4) Label DD3 on sheet SW3.
13. (Rev.3) SW4 - Identify what T & G squares are adjacent to ramp. Fix location where SF
shown for san. sewer line offsite.
(Rev.4) Addressed.
Process
After approval, plans will need to be bonded. Applicant prepared and sent Albemarle an estimate of ESC and SWM
bond amounts. Applicant’s estimates will inform and improve county bond estimates, and are very helpful. Please
continue to work with Ana Kilmer, Management Analyst, to post bonds (434.296-5832 –x3246). Plan reviewer
intends to submit bond estimates to Ms. Kilmer that generally align with Applicant’s bond estimates.
Deed of Dedication is recorded at Albemarle County Circuit Court land records book 5064, page 527.
After bonding is 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 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.
Final Note: Purchase of 2.16 lb. (phosphorus) Nutrient Credits must be complete prior to receiving Grading Permit.
County forms can be found on the county website forms center under engineering;
http://www.albemarle.org/deptforms.asp?department=cdengwpo
File: WPO201700056-Springhill~TownplaceSuites-VSMP-ReviewComments-062718Approval.docx