HomeMy WebLinkAboutWPO202200036 Review Comments WPO VSMP 2022-09-08�q off nig 401 McIntire Road, North Wing
Charlottesville, VA 22902-4579
County of Albemarle Telephone: 434-296-5832
COMMUNITY DEVELOPMENT DEPARTMENT WWW.ALBEMARLE.ORG
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VSMP Permit Plan Review
Project title:
Overlook Hotel
Project:
WP02022-00036
Plan prepares
Shimp Engineering, 912 E. High St., Charlottesville, VA 22902
Chris Marshall, PE — chris e shimp-en ing eerieg com
Owner /Applicant:
WS Four LLC, 3600 Pacific Avenue, Virginia Beach, VA 23451
doug(i�subcao.com
Plan received date:
12 Aug 2021
Date of comments:
8 Sep 2022
Reviewer:
John Anderson, PE, CFM
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 ESCP, (3) a SWMP, and (4) any TMDL measures necessary.
SWPPP
1. Please ensure SWPPP cover includes reference to WP02022-00036.
2. Submit SWPPP' using county template located at:
httos: //www.albemarle. ore/home/showDublisheddocument/ 166/637202310327530000
a. ' Sec. 1, VAR10 permit registration, has been submitted.
b. Sec. 6.A.: PPP Exhibit: Please show initial location of:
i. Rain gauge.
ii. Portable sanitary facilities (ports John), as required.
iii. Covered non -hazardous waste dumpster, if required.
iv. Vehicle wash waters, draining to trapping measure (Not a sediment trap design, per se,
but shallow depression — 1-2 backhoe buckets. Avoid direct drainage to Ex. storm
system.)
v. Concrete wash -out.
vi. On -site fuel, if required.
vii. Paint, stucco, chemical storage, if required.
c. Sec. 6E: List named individual responsible for PPP measures.
d. Sec. 8: Although Albemarle County will inspect, Applicant is required to retain qualified
(contractor/third-party) E&S inspection personnel to perform ESC inspections and evaluate
compliance relative to VESCH, Yd Edition, 1992.
e. Sec. 9: Ensure Signed Certification is signed and dated.
B. Pollution Prevention Plan (PPP) —see SWPPP item 2.b., above
The PPP content requirements can be found in County Code section 17-404.
C. Stormwater Management Plan (SWMP)
Engineering Review Comments
Page 2 of 9
VSW Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWW. This
plan is disapproved for reasons listed below. The stormwater management plan content requirements can be
found in County Code section 17-403.
C2
1. General /Calculation packet:
a. Although proposed design need not reduce bypass flow (offsite-to-offsite), pipe capacity calcs
must include 24" HDPE bypass storm conveyance pipes in LD-229 table, calc. packet, p. 45.
b. Pg. 45:
i. From A9 to A8, 1.70 cfs peak flow exceeds pipe capacity, 1.3cfs. Please revise.
ii. From A7 to A6, 3.07 cfs peak flow exceeds pipe capacity, 1.6cfs. Please revise.
iii. From A6 to A5, 4.60 cfs peak flow equals pipe capacity, 4.6cfs. Increase pipe DIA, or
pipe slope to ensure adequate capacity.
iv. From A4B to UGS, 3.47 cfs peak flow exceeds pipe capacity, 2.8cfs. Please revise.
c. Pg. 44: Revise LD-204 to include new storm inlet east of hotel entrance on U.S. Rt. 250 EBL.
d. Include WPO202200036 on calculation packet cover.
2. Include WPO202200036 in plan title, sheet Cl
3. Show /label managed steep slopes. Also applies to any grading, site, utility, or E&S Phl,2,3 plan sheet. It
is insufficient to show steep slopes only on ex. conditions sheet, since comparison with improvements or
grading is critical to review.
4. Show Aabel existing tree line.
5. Show /label existing sidewalk fronting SunTrust bank, U.S. Rt. 250.
6. Show /label existing drainage feature on TMP 78-13A as perennial, intermittent, or defined channel (dry
watercourse).
7. Show label surface features on TW 78-13, including buildings or surface parking that overlay contour
areas depicted.
8.
9.
10.
Label apparent fence on TMP 78-13A that intersects Cl boundary ofTW 78-73A7
SF from prior development, provide label that ex. silt fence is to be removed.
Show /label existing easements on TMP 78-73A7 and 78-13A.
If this feature is relic
ex. wall:
C3
Engineering Review Comments
Page 3 of 9
11. Label existing storm pipe roughly parallel to parcel boundary at U.S. Rt. 250.
12. Label ex. inlet west of proposed entrance to Overlook Hotel `to be removed.'
13. Label retaining wall at SWM facility.
14. Shift /reorient (with leader line) `47 LF 12" HDPE' label since it obscures A2 structure label.
15. Revise 47 LF 12" HDPE to 15" HDPE, consistent with C5 profile.
16. Show /label CG-12 either side of hotel entrance.
17. Provide inlet on U.S. Rt. 250 immediately east of entrance to replace inlet removed immediately west of
entrance. U.S. Rt. 250 runoff should be captured prior to crossing hotel entrance.
18. Tie new storm pipe serving DI east of entrance to existing /proposed bypass storm conveyance west of
entrance, south of U.S. Rt. 250 EBL. Pipe should run beneath entrance.
19. Provide, show, and label a public drainage easement over inlet /storm pipes that convey runoff from U.S.
Rt. 250 or north of U.S. Rt. 250 to daylight south of U.S. Rt. 250. A public drainage easement is required
over all elements of storm conveyance that carry runoff from U.S. Rt. 250, or areas north of U.S. Rt. 250.
20. Stepped retaining walls located on TMP 78-13A require permanent easement. Provide easement prior to
WPO plan approval, or prior to final site plan approval, latest.
21. Extend guardrail that ends 5 spaces south of parking lot island (near `118 LF 15" HDPE label) to last
parking space at south corner of parking lot, immediately adjacent to dumpster enclosure.
22. Existing sidewalk at U.S. Rt. 250, TMP 78-13A, may be mistaken as proposed, please label Ex.
23. (Entrance / FSP: 25' egress and 35' ingress radii are insufficient for land use. Ref commercial /office land
use in Table 4-3, VDOT Road Design Manual, Appendix F. With FSP, provide Autotum fig. using SU-30
design vehicle to show outbound vehicles do not cross an outer travel lane, U.S. Rt. 250 EBL, and that
inbound vehicles do not mount curb /walk. 25'/35' do not meet VDOT Access Management requirements.)
24. Offsite surface detention basin requires maintenance agreement with owners of TMP 78-73A7 and 78-13A.
25. Offsite retaining wall (TMP 78-13A) requires retaining wall maintenance easement (TMP 78-13A, Grantor,
to TMP 78-73A7 Grantee), independent of any other easement. Retaining wall maintenance easement and
SWM facility easements may overlap.
26. Label typ. parking space L x W at 15 spaces south of /behind hotel. Provide clearance required to avoid
conflict with retaining wall. Ref ACDSM, 7.C.6.. p. 17 of Manual. [ FSP-related.]
Engineering Review Comments
Page 4 of 9
27. If proposed stepped retaining walls parallel with TMP 78-73B1+ or TMP 78-7IM require (permanent)
geogrid placement or temporary construction access to construct improvements, provide required
easements as condition of WPO plan approval.
28. Show off -site features downslope of detention pond emergency spillway to at least edge of existing
pavement (car dealership parking lot), and provide relief for emergency spillway flow that does not convey
emergency spillway flow across auto dealership parking lot. Label structures, pipes, conveyance required
to capture emergency spillway flow. Provide public drainage easement across off -site parcels for storm
conveyance below SWM facilities until SWM discharge reaches a natural receiving stream, likely
downstream of auto dealership parking lot.
rgency spillway discharge)
,ok Hotel.
C4
C5
Engineering Review Comments
Page 5 of 9
29. Provide spot elevations at EP U.S. Rt. 250 EBL and in entrance throat to ensure Rt. 250 runoff does not
enter site, and to delineate flowline aligned with U.S. Rt. 250 CG sections E-W of entrance.
30. Remove sidewalk and CG linework across hotel entrance.
31. Show CG12 and new sidewalk connecting to ex. sidewalk, either side of hotel entrance.
32. A building permit is required for wall ht. >3-ft.
33. (PE-) Sealed retaining wall design is required for wall ht. > 4-ft. Please submit to Engineering prior to
WPO plan approval, given integral relationship to storm pipe, grading, and SWM facility.
34. Provide SL-1 labels, Str A2 and A3 (safety slab).
35. Revise 47 LF 15'HDPE @12.8%to 47 LF RCP @ 12.8%.
(Mote: 47' pipe penetrates stepped retaining wall: this pipe is partially in cut, over half its length in fill.
This pipe may not deform, crack, etc. RCP or DIP (not CMP) is required for this pipe section. HDPE may
NOT be substituted for RCP by contractor or design engineer during construction at this location.)
36. Provide lintel detail where 47 LF RCP penetrates retaining wall, provide ref to lintel detail on storm pipe
profile.
37. Provide note concerning and requiring adequate compaction for storm structures or pipes in fill, which is
majority of storm conveyance upstream of 4640 SF R-Tank Underground Storage. Fill beneath storm
structures and pipes approaches or exceeds 20' in certain locations.
38. Provide additional profile labels for 4640 SF R-Tank Underground Storage, including geogrid and at least
label ref. to 3" min. base material to help establish grade for R-Tank installation, convey design intent, aid
inspection, minimize error, and avoid misunderstanding during construction.
39. Note: Critical installation steps of detention basin, R-Tank Underground Storage, and retaining walls,
particularly adjacent to SWM, require licensed engineer or qualified manufacturer's technical inspection to
affirm suitability of bearing strata, subgrade compaction, backfrll, underdrain /weep placement, suitable fill,
adequate depth, etc. to confirm and ensure wall foundations subject to saturated conditions or supporting
hotel parking, aisles, or structures are not compromised by periodic inundation /submersion during rain
events (detention pond), or excessive vehicle surcharge /geotechnical forces. Provide notes on plan
requiring qualified geotechnical installation inspection, certification, and reporting /recordkeeping.
C7
CIO
Engineering Review Comments
Page 6 of 9
40. Emergency spillway may not be placed in fill without proper analytic design, and armoring. Ref. VA DEQ
Stormwater Design Specification, Appendix A Earthen Embankment. Provide design for detention pond
emergency spillway in fill.
41. Label detention pond top of embankment elevation. Ensure top of embankment ht. >_463.95'. C3 indicates
`top of dam' elev. =464'.
42. Label detention pond floor elevation.
43. Detail 2 (Storm profile AO -Ex. 24" RCP):
a. Label Sir. AO, Al, 130, BI, B2.
b. Provide INWRIM data and inlet /MH type for each storm structure (descriptive labels).
c. Shift pipe captions L/DIA/slope so captions lie below pipe they describe.
d. Profile indicates MH located in detention pond embankment, inconsistent with C3 Site and Utility
plan. Review profile and plan for accuracy /consistency. Revise profile as needed.
44. Label pipe slope between Str. A4 and R-Tank Underground Storage.
45. Label pipe DW IN elevation at R-Tank, from Sir. A4.
46. Label R-Tank top elevation, appears to be 481'.
47. Detail 1: Label INV OUT, Str. Al.
48. Provide label requiring %:" steel plate in floor of MH Sir. Al. Ref VDOT Drainage Design Manual, Ch. 9,
Stone Drains, 9.4.8.7, Max. Grade.
49. Delete second sentence of text block in text box in upper right of plan sheet. "The sediment basin [shown
on TMP 78-13A] can remain after construction." This is incorrect. Once upslope areas are stabilized, the
sediment basin must be converted to SWM detention basin. ESC measures may not persist for future
development since ESC measures are temporary, future development is never certain, the feature will be
bonded as a SWM facility /bond could not be released, and plan indicates surface detention is required to
meet SWM quantity requirements. If this is not the case, that is, if pond is not needed to provide SWM
quantity control for Overlook Hotel, then notes and labels should indicate the sediment basin will be
removed and not converted to SWM control, once upslope areas are stabilized. Also, item 64.a., below.
50. At Str. 4, provide INV IN 47 LF 8" PVC from roof leader line.
51. Provide /label storm profile: yd. drain roof leader line system behind (east of) hotel.
52. The surface detention pond will detain surface runoff from grading and land use on TMP 78-13A. Ref. C4
and SWM Quantity note, C7. Clarify SWM Quantity note (slight text revision) to indicate surface
detention is required for Overlook Hotel development, and will be converted to a SWM facility once
upslope areas are stabilized, and it is no longer needed as a sediment basin for the Overlook Hotel
development.
53. Revise pipe material for storm drain that passes beneath tiered retaining walls. Commend design that
selects least problematic location for crossing wall, but every attempt must be made with design and during
construction to ensure longevity and maintenance -free performance of this particular pipe: revise pipe
material type to RCP. Comment may repeat.
54. Provide lintel design for retaining wall pipe crossing. Note: this pipe is within public drainage easement.
55. Note: VDOT Land Use Permit is required for work within public RW, U.S. Rt. 250, Richmond Road.
56. (FSP-related) Since road plan not required, provide evidence of coordination /approval of a Maintenance of
Traffic Plan with VDOT (MOT) with WPO Application (since ties to land disturbance), or not later than
final site plan (FSP) review /approval. A MOT with restriction on hours of operation will likely govern
work within VDOT RW, U.S. Rt. 250. An approved WPO plan and Grading Permit do not authorize
construction within U.S. Rt. 250 public RW. VDOT maintains jurisdiction over activity within, or
disturbance within public RW.
57. It is unclear whether runoff from development reaches surface detention pond (no inlet pipe/s), please
confirm design intent and whether surface detention is to intercept surface sheet runoff only.
Engineering Review Comments
Page 7 of 9
58. Review potential of undeveloped parcels with relatively low curve numbers north of U.S. Rt. 250 to
increase runoff since Overlook Hotel proposes to pipe /encase existing drainage feature. It is unclear if a
24" HDPE provides adequate capacity for either existing or future development in the upslope watershed.
Please consider undeveloped parcels that may contribute additional runoff to the existing storm system
I photo, below.
59. TWBW 92/85.5 at dumpster enclosure exceeds wall Max. ht. for managed steep slopes, 18-30.7.5.A.1.
Revise to limit wall ht. to 6' Max.
60. Provide stand-alone SWM plan:
a. VSMP /WPO plan includes Mir. details for R-Tank underground storage, installation, operation,
inspection, and maintenance, which is excellent (C13, C14). C15 includes Construction Record
Drawings (As -built) for VSMP. In addition, on a SWM plan sheet (C16 or C15), please provide:
i. Letter of nutrient credit availability (required for plan approval).
ii. VaRRM.x1S site summary tab.
iii. SWM quality /quantity narrative (relocate from C7, E & S Narrative).
iv. Summary quantity /quality calculations —for example, include EB equation on the plans.
Table -chart, p. 40 of calculation packet, for example.
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.
61. C4
a. Provide recorded permanent grading easement with adjacent parcel, TMP 78-13A, Happy Boxes
Pantops, LLC.
b. Related: provide copy of notarized agreement or recorded temporary construction access easement
with owner of TMP 78-13A. Ensure temporary construction access easement extends from areas
to be graded to U.S. Rt. 250 at such point that construction vehicles may exit Rt. 250 via asphalt
ramp or commercial entrance and at a point approved in advance by VDOT.
62. C8
a. Provide show label paved construction entrance at U.S. Rt. 250 EBL.
Engineering Review Comments
Page 8 of 9
b. Eradicate linework for ex. U.S. Rt. 250 C&G /sidewalk if removed in Phl.
c. Remove proposed entrance radii linework and lines /curve delineating edge of parking lot at
approx. contour 470' (that bisects trap 3).
d. Provide short length of on -contour SF a short way downslope of trap weirs, in E & S Plan PH I.
e. Shift STI, ST2 at least 2' downslope to ensure DD functions and there is sufficient fall from NW
comer of site to STI. This should not conflict with wall construction downslope.
f. Provide TS, PS, MU for pipe installation AO to B2.
g. Revise sequence to describe by-pass for runoff that daylights /exits 24" RCP beneath /south of
U.S. Rt. 29 EBL. It will take days for 385 LF 24 HDPE to be installed, and ESC measures for 24"
bypass are critical to ensure no offsite incident or impacts downslope to auto dealership parking.
Existing drainage 10-yr event is likely considerable, provide bypass during construction of 24"
HDPE conveyance.
63. C9
a. Offsite ESC controls (TMP 78-13A) require offsite owner be party to WPO plan bond and will
require right of entry Agreement to ensure Albemarle has right to enter and inspect ESC measures.
b. Show /label proposed contours (grading) at this phase, including at ends of retaining walls (tie
grading to existing grade).
c. Show material or soil stockpile, this phase, as needed.
d. Revise trap labels to: STI, ST2, ST3.
e. Provide TS, PS, MU at this phase, where and as needed.
f Clarify how runoff reaches traps STI, ST2, given proposed grade at this phase.
g. Provide RWD as necessary if construction equipment must cross diversions.
h. Remove STI DA text box, not needed in PH2 since shown in PHI.
i. Resolve ST3-retaining wall conflict, since shown to overlap.
j. Show Aabel paved construction entrance on U.S. Rt. 250.
k. Eradicate linework for ex. U.S. Rt. 250 C&G /sidewalk if removed by Ph2.
1. DD shown in Ph 1 are not shown in Ph2; clarify how Ph2 runoff reaches STs in Ph2, relative to
proposed grading, Ph2. Also, C9 item b., above.
m. Provide interim ESC measures needed to place backfill at stepped retaining walls that approach
20-ft. ht. in location of ST3, which cannot occupy this space during wall construction.
n. Recommend remove guardrail linework, unless installed in Ph2.
o. Recommend remove extraneous linework that encircles hotel.
p. Provide access to sediment basin trap during this phase of construction. Show on plans. Ensure
construction access is traversable by AWD vehicles and construction equipment.
q. Provide paved construction entrance to 78-13A for sediment basin trap construction, during this
phase.
64. C 12
a. Contributing DA to proposed sediment basin is too small to qualify for this ESC measure.
VESCH states (Conditions where practice applies) "Below disturbed areas where the total
contributing drainage area is equal to or greater than three (3) acres." DA =1.48 Ac., which yields
impractical A, B, C values in basin design table: 0.5' vertical difference between floor of basin
and clean -out level, for example. An SB is not appropriate, and will not be approved. Revise
measure to sediment trap (ST4).
b. Provide ST4 design data.
c. Additional comments possible.
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,
Engineering Review Comments
Page 9 of 9
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 24 weeks to obtain all the correct signatures and forms.
Stormwater Management Facilities Maintenance agreements will also have to be completed and are 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.
This project proposes nutrient credit purchase (2.26 Ibs.l and requires SWM facility and SWM facility access
easements. This project may also require forest -open space easement (for SWM purposes).
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.
After DEQ coverage is issued, via the coverage letter, 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 Applications:
httos: //www. albemarle. ore/government/community-develonment/aooly-for/engineering-anol is ations
Thank you.
Please call if any questions — tel. 434.296-5832-x3069, or email ianderson2&albemarle.org.
WPO202200036—Overlook Hotel-090822