HomeMy WebLinkAboutSDP202200027 Review Comments Initial Site Plan 2022-06-17� AI
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 229024596
Phone (434) 296-5832 Fax (434) 972-4126
Site Plan review
Project:
Avon Court Industrial Building - ISP
Project file number:
SDP2022-00027 (Also, SDP2021-00003)
Plan preparer:
Scott Collins, Collins Engineering [200 Garrett St., Suite K, Charlottesville, VA
22902, scott(a)collins-engineering.coml
Owner or rep.:
Avon Court Holdings, LLC, P.O. Box 1467, Charlottesville, VA 22902
Riverhead Development, 455 2°d Street SE, Suite 200
Charlottesville, VA 22902 lsimpson(d�riverbenddev.com
alanAriverbenddev.com ]
Plan received date:
(I I Jan 2021, SDP202100003)
17 May 2022 (ISP-b.)
Date of comments:
(10 Feb 2021)
16 Jun 2022 (ISP-b.), Rev. 17 Jun 2022
Reviewer:
John Anderson, PE, Engineering Div.
Project Coordinator:
(Cameron Langille, SDP2021-00003)
Rebecca Ragsdale, Planning Manager, Planning Div.
Please address comments below with the Final Site Plan (FSP)
1. C-1
a. Floodplain Information: Please revise Eff, date to May 16, 2016 consistent with 18-30.3.2. (ISP-
b.) Addressed.
b. Recommend SWM Note reference WPO2021-00002 (WPO plan is under review). (ISP-b.)
Addressed.
2. Sheet 2
a. Legend assumes a reclassification that is not automatic, or complete. See 18-30.7.6, Amendment
of district boundaries specifies whether/how steep slopes (preserved /managed) may be removed
from the steep slopes district. ISP assumes approval, prior to approval. Revise FSP and
development design consistent with existing steep slopes. Alternatively, pursue process
established by ordinance for removing steep slopes from the steep slopes overlay district. ((ISP-
b.) Partially addressed /may persist. Applicant response (letter d. Mar 2, 2022): `Attached is the
steep slope analysis based on field run topo. Much of the existing preserved steep slopes remained
preserved steep slopes. The layout has been updated to remove the impacts of the preserved
slopes in this area. The plans match the steep slope analysis and the impacts to the preserved steep
slopes have been removed. The improvements and the grading on the plans have been updated,
and there are no proposed impacts to the preserved slopes on the property.' Engineering has
coordinated with Planning. As ollow-up (please):
i. Engineering is supportive of data (1-p. graphic study) received with ISP submittal. As
follow-up:
1. Please revise title ofAvon Court Initial Site Plan Slope Analysis to `Avon Court
Initial Site Plan Field -Survey Steep Slopes Exhibit.'
2. Date Exhibit.
3. Include brief narrative.
a. Include reference to SDP202200027.
Engineering Review Comments
Page 2 of 6
b. List area (W) of preserved steep slopes to be treated as managed steep
slopes (<25%).
4. Include date of field run survey.
5. Include survey firm that conducted field run survey.
6. Include identifying information for Collins Engineering (firm, address, tel.,
email).
7. Edit labels which read `Preserved steep slopes classified as managed slopes
based on field run topo elevations,' to read `Preserved steep slopes to be treated
as managed steep slopes based on field run topo elevations' (unless otherwise
instructed by Zoning/Planning).
8. Recommend include outline of improvements in vicinity of currently mapped
preserved steep slopes (i.e., building footprint, EP, etc.: outlines with labels
(proposed drive aisle, parking, building, etc.)).
ii. Sheet 2: Planning confirms preserved steep slopes shown by survey to be <25% may be
treated as managed steep slopes, though they are not re-classified as managed, or as non -
steep slopes. Slopes remain preserved slopes, but ordinance provides [18-30.7.4.b.l.h.]:
Any use or structure allowed by right or by special use permit in the underlying
district, provided that the owner submits new topographic information that is
based on more accurate or better technical data demonstrating, to the satisfaction
of the county engineer, that the slopes are less than 25 percent.
Reclassification from preserved to managed requires board of supervisors' action. Given
this, please edit final site plan legend to show: preserved slopesmanaged slopes, and
preserved slopes with uses permitted on managed slopes, based on field run topo analysis
[unwieldly, but accurate].
b. Revise legend, per review item 2.a. above. (ISP-b.) May persist. Also, item 2.a.ii. above.
c. Provide circuit court deed bk.-pg. references for RW dedication /various easements. (ISP-b.)
Persists.
3. Sheet 3
a. 13' site access on south side of industrial building does not meet min. 2-way access width (20');
portion of site access south of building is eligible for 1-way access. Provide 1-way pavement
marking, No Entry sign/s, 1-way travel signs, etc. [ 18-4.12.17.c.2.] (ISP-b.) Addressed.
-: Applicant response to remaining SDP2021-00003 Engineering ISP review comments (save
item 17.): `This comment will be addressed with the final site plan.' Engineering accepts response
applies to items 3.b.-h., items 4: 16., which will be checked against the final site plan. Remaining
Engineering ISP review comments (may) persist.
b. 13' width on south side of building is inconsistent with Site Plan Note 5. please reconcile.
c. Provide site access profile showing smooth transition, Avon Court, proposed -to -existing.
d. Coordinate with VDOT to ensure state will accept portion of Avon Court proposed with ISP.
(Coordinate since Avon Ct. at this location does not appear to serve at least 3 separate entities.)
e. Coordinate 13' access width south of building with ACSA, to ensure adequate for fire rescue
vehicles.
f. Provide Avon Court typical road plan details:
i. Profile, w / VC -tangent design data.
ii. LD-204, LD-229.
iii. Pavement section based on peak ADT.
iv. Pavement design capable of supporting fire apparatus weighing 85,000 lb. (Note 5).
v. (Remaining) Civil details.
g. If industrial building will have security fence or entrance gates, recommend show on FSP.
Engineering Review Comments
Page 3 of 6
h. No portion of retaining wall located on managed or preserved steep slopes may exceed 6' ht.
Max. ht. of portions of retaining walls not on steep slopes is 10' (requirements at 18-4.3.3.A.1.
provide TWBW elevations to aid review, especially for portions located on steep slopes.
4. Sheet 4
a. Wherever curb concentrates runoff, provide CG-6 (south of building, for example).
b. Provide spot elevations to aid review and help ensure no nuisance ponding.
c. Revise proposed grading on preserved steep slopes (highlight, below), since impermissible.
d.
e.
f.
g
_
"MG 'N.
SWERM BViEER
IDPLAiN
PRESERVED "
SLWEs
MOORE'S CREEK
Note: More accurate field survey data showing slopes <25% may be used to prepare an Exhibit for
review (to request
removal of setions of slopes from steep slopes overlay district —also, item 2.a.
above).
Label managed steep slopes along north side of site /N PL, E and W of dry detention basin `A'.
Label all slopes steeper than 3:1.
At top of 8' wall at west end of site, provide GR-2 guardrail.
Provide GR-2 behind curb along access on S side of building, since 14'(f) vertical interval to
stream is unrecoverable.
h. Provide GR-2 for blue -circle parking spaces:
5.
0
Engineering Review Comments
Page 4 of 6
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i. For inlet and pipe conveyance leading from cul-de-sac, Avon Ct. to dry detention basin `A',
provide and label public drainage easement.
Sheet 5
a. Tom on drainage layer (pipes /inlets) to aid review of potential landscape -drainage conflicts.
b. Recommend Landscaping Plan identify groundcover species hardier than grass (not Lespedeza)
for any proposed slopes steeper than 3:1.
c. Additional comments possible.
Sheet 7
a. Drainage Note 4: Revise sheet 4 proposed public drainage easements to extend from outfall of
each SWM facility to `a natural watercourse.'
b. Provide CG-6 wipe down detail.
Engineering Review Comments
Page 5 of 6
7. Sheet 8
a. Revise Water Quantity Summary Narrative to reference stormwater conveyance downstream of
underground detention /dry detention basin. Although mapped floodplain does indicate limits of
analysis for flood control [9VAC25-870-66.C.3.c.], at mapped floodplain on this site there is a
pronounced 4' vertical drop, 360' to 356'. MS-19 requires measures to limit erosion impact/s to
adjacent /offsite parcel/s (City of Charlottesville, in this instance).
b. 9VAC25-840-40.19.a. applies to both underground detention and dry detention basin `A'.
Excerpt:
19. Properties and waterways downstream from development sites shall be protected from sediment
deposition, erosion and damage due to increases in volume, velocity and peak flow rate of stormwater runoff
for the stated frequency storm of 24-hour duration in accordance with the following standards and criteria.
Stream restoration and relocation projects that incorporate natural channel design concepts are not man-
made channels and shall be exempt from any flow rate capacity and velocity requirements for natural or man-
made channels:
a. Concentrated stormwater runoff leaving a development site shall be discharged directly into an
adequate natural or man-made receiving channel, pipe or storm sewer system. For those sites where
runoff is discharged into a pipe or pipe system, downstream stability analyses at the outfall of the pipe or
pipe system shall be performed.
SWM analysis is thoughtful. Erosion analysis prompts request for adequate man-made receiving
channel to such point erosion effects abate. Dry detention basin `A' is provided with a riprap
outfall, but not a receiving channel. Concentrated stormwater runoff leaving a development site
shall be discharged directly into an adequate natural or man-made receiving channel, pipe or storm
sewer systm. Adequacy of all channels and pipes shall be verified in the following manner:
b. Adequacy of all channels and pipes shall be verified in the following manner:
(1) The applicant shall demonstrate that the total drainage area to the point of analysis within the channel
is 100 times greater than the contributing drainage area of the project in question; or
(2) (a) Natural channels shall be analyzed by the use of a two-year storm to verify that stormwater will not
overtop channel banks nor cause erosion of channel bed or banks;
(b) All previously c tmcte an -made channels shall be analyzed by the use of a 10-year storm to verify
that stormwater will no rtop its banks and by the use of a two-year storm to demonstrate that
stormwater will not c e e ion of channel bed or banks; and
(c) Pip nd storm sewer systems shall be analyzed by the use of a 10-year storm to verify that
sto water 'It be contained within the pipe or system.
Emphasis of 9VAC25-840-40 (Minimum standards) differs from 9VAC25-870-66 (Water
quantity): requirements Aimits of analysis differ slightly. Note: Horizontal limit of floodplain are
not point of comparison for b(l), above. Rather, Moore's Creek is. b(2)(a) is NA [dry detention
basin /UG detention do not discharge to natural channels, but to slopes], b.(2)(b),(c) are NA.
c. Per 9VAC25-840-40.19.g., provide a receiving channel. ISP design proposes riprap outfall for the
detention system, not a receiving channel. Project receiving channel must discharge to an existing
natural channel, stream, or such point that channel characteristics yield to relatively flat terrain:
g. Outfall from a detention facility shall be discharged to a receiving channel, and energy dissipators shall
be placed at the outfall of all detention facilities as necessary to provide a stabilized transition from the
facility to the receiving channel.
d. Note: WP02021-00002 VSMP plan has been submitted; review is pending.
e. Albemarle avoids request for revisions not supported by Code /ordinance. Note: Immediately N of
development property (TMP # 07700-00-00-00900), 3/22/19 inspection of flume across preserved
steep slopes to streambank at Moore's Creek illustrates erosion even within floodplain [photo,
Alb. County, below]. MS-19 supports request for man-made channel sized to convey the 10-yr
event between contour elev. 360' to 354', designed to resist erosive velocity (Vel2-y,).
General
8.
9.
10
11
12
13
14
15
Engineering Review Comments
Page 6 of 6
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f. Provide copy of deed of easement with City to construct channel between contour 360 and 356' on
city property. (Public drainage) easement with City must be recorded prior to WPO plan approval.
g. SWM facility easements must be recorded prior to WPO plan approval (dry detention basin `A'
and underground detention).
h. Provide SWM access easement (plat) from SWM facilities to public RW. May show on same plat
as SWM facility easement/s. Record SWM access easement prior to /for WPO plan approval.
i. Provide vehicular SWM access easement to dry detention basin `A' that accommodates proposed
retaining wall. Vehicular access proximate to basin riser is required.
j. Ensure ESP is revised consistent with revised WPO202100002.
Provide safety railing for retaining walls > 4-ft. high. Show Aabel safety railing in plan view.
Provide TWBW data, all retaining walls, to aid review and construction.
Include ESP notes requiring flagging of all preserved steep slopes, prior to construction.
Ensure ESP grading complies with requirements at 18-4.3.3, Grading Standards.
Provide VDOT LD-204, LD-229 inlet and storm pipe computations (tables).
Label all curbing.
FSP approval requires approved WPO plan.
WPO plan approval requires FDP (floodplain development permit) application for man-made conveyance
in floodplain.
16. An approved FDP Application requires a `No RISE' Certificate.
17 D....:. e typ:eal ei it d@tai . DB 1 re 1 ST 1 er 1 ➢ 14 1 _ rISP-b.) Withdrawn. Applicant: `VDOT
details are no longer allowed to be included on plan sets, per VDOT and copyright requirements.'
Please feel free to call if any questions: 434.296-5832-x3069.
Thank you
SDP202200027_SDP2021-00003 Avon Court Industrial Bldg ISP 061722rev