HomeMy WebLinkAboutSUB202000098 Review Comments Road Plan and Comps. 2020-07-16COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Subdivision Plan Review
Project title: Galaxie Farm ROAD Plan
Project file number: SUB2020-00098
Plan preparer: Shimp Engineering, Justin M. Shimp [ justinna,shimp-en ing eering com ]
Owner or rep.: Jasper L or Mallie P Haynes, P.O. Box 422, Charlottesville, VA 22902
Plan received date: 21 May 2019
Date of comments: 16 Jul 2020
Reviewer: John Anderson
Note: Comments overlap /repeat preliminary plat Engineering review comments (SUB201900198, 2/l/20).
To the extent design was revised in response to preliminary plat (road -related) comments, please disregard
comments that are repetitive, or not applicable.
Cl
C2
1. Ensure land use schedule impervious area is consistent with WPO plan for this development.
2 Nete Please submit WPO plan f r deyel pment at eafliest , o 0 e. WO received (WP0202000037).
3. C2 does not clearly indicate two parcels. There are two parcels. Please show current parcel boundaries.
4. Label Cow Branch.
5. Label steep slopes (preserved /managed).
6. Note: If roof runoff is proposed to be collected and conveyed via leader lines to drop inlets or will intersect
proposed 15" DIA storm lines, show leader lines.
7. Please consider recent Building Inspections Div. guidance which may influence design of retaining walls or
affect plan approval. Albemarle County Building Official advises that: "Retaining walls shall either be
independent and terminate at the property [read, lot] line or an easement and maintenance agreement shall
be executed between property owners involved." We mention this now so that it does not cause issues, or
delay or impede subsequent plan (or building application) reviews /approvals.
C4:
8. Label lots. Also applies to CT C8.
9. Please examine remnant existing and proposed contours on Lots 7-11. Provide storm runoff capture
/conveyance such that surface runoff does not cross more than 3 lots, without capture /conveyance. Ref.
Drainage Plan Checklist for plan reviewers, p. 1, Drainage section, last item. [ yard inlets appear to be
required ]
10. Lots 53-56 runoff is shown sheeting across Road E. Provide drainage to intercept sheet runoff and convey
via street -side pipes or yard inlet pipe system. Design must prevent offsite runoff from traversing Road E
street surface.
11. Provide temporary (off -site) construction /permanent grading easement/s as needed to construct proposed
retaining wall across parcel lines, Lots 1-7.
12. (C7, C 12): Calculate depth in roll-top gutter, Road E. Ensure runoff does not enter driveways (esp. Lots
57,58).
13. C3, C4: 8' wide ditch crossing lots 23 thru 38 is an infeasible design. Revise surface ditch to subsurface
drainage (inlet /pipes). Owner of multiple lots may flatten obscure ditch and disrupt drainage since each lot
Engineering Review Comments
Page 2 of 7
has such limited lawn area. A surface ditch design crossing 15 lots will not in this instance be approved.
(Recall homeowner resistance to swale construction across lawn areas at Hillbrook Subdivision.)
14. Similarly, provide subsurface storm runoff collection /conveyance for Lots 15-22.
15. Ensure storm runoff from impervious areas, Lots 15-38 is conveyed and treated or detained, as needed, to
comply with state or local code, including MS-19. It appears a necessity that given close proximity to
property line to SW that impervious rooftop storm runoff must be collected, since splash block -only
discharge cannot transition to sheet flow in limited space available (Lots 15-22, especially).
16. C4:
17. Provide guardrail, Road F, at stream crossing. Alternatively, provide 12:1, 4'-wide graded shoulders before
transitioning to steeper embankment grades. Infrequent use reduces but does not eliminate risk posed by
unrecoverable slope with z7.25' vertical drop to streambed.
18. C4 (C6, C8): Ensure lots are located entirely outside the (100') stream buffer. Ref. ZMA Sheet 71 Note F.
Portions of Lots 57, 58, 59 appear to be within stream buffer.
19. C5: Provide additional preliminary design detail for transition from Road A2 to Ex. Galaxie Farm Lane
which provides access to multiple parcels beyond proposed development. Note reading Connect Galaxie
Farm Lane to new road is insufficient for an existing road that must remain in continuous use. Compare
spot grade at transition to Galaxie Farm Lane at end of Road A2 to existing Elev. of Galaxie Farm Lane.
Provide preliminary travel way design and drainage to ensure smooth transition.
20. C5, C6 (Subdivision Lam), and CT C8 (Grading and Utility Plans) mix incomplete views of easements,
and utilities. For example, C5, C6 show ACSA easements, but not all. For example, C5 does not provide
ACSA waterline easement south of Road Al in the direction of Rt. 20, to include new FH near Int. Rt. 20.
New ACSA water easement is shown along Road E, with utility schematic (C7), allowing easy check of
easement. Provide and label all utility easements on C7, C8.
C5/C6
21. Show /label CG-12 ramps wherever sidewalks intersect roads [@ intersections of Roads: B 1-A2, 132-A2,
B1-A1, Al-D, 132-C, C-E, at entrance to parking area SE of Open Space C ].
22. Provide and label traffic control signs: stop, no parking, speed limit.
23. Provide and label street name signs.
24. Show intersection sight distance lines for internal street intersections.
25. C5
a. Lot 60: Provide Auto -turn figure to show vehicle reversing from driveway clears N-bound lane
completely before advancing in a forward direction. If Road E is insufficient length, a typical
passenger vehicle will strike curb or run off Road E before it clears N-bound (in -bound) lane.
b. Provide fixed barriers both as pedestrian protection and to prevent vehicles from running off the
end of Road E. A curb -less design at N end of Road E cannot be approved. Provide guardrail
pedestrian protection between end Road E, and Road Al sidewalk. Provide curb at end Road E.
c. Lots 57, 58: Drive entrances propose acute angles (>90-deg). Provide Auto -turn figures to show a
typical passenger vehicle may enter driveways without running off paved drives and onto lawns.
d. All subdivision Lots: Related to 25.c., revise all driveway widths to 12' (Absolute Minimum; see
VDOT CG-9D). Also, item 40 below. Please apply CG-9D Min. drive width to this/future design.
e. Lots 48-50: Driveway entrances problematic relative to angle with cul-de-sac, or location in radius
curve sections of curb. Provide perpendicular driveway /street intersections. Relocate driveways
out of curved sections of cul-de-sac curb.
f. Show sight distance lines (left/right; NE/SW) at Int. Road Al and Route 20.
g. Label highlight line -type, image below. If an easement or setback, this line intersects structures
(likely impermissible).
26
27
Engineering Review Comments
Page 3 of 7
C5(-C 13, 8 sheets): Show driveway entrance radii graphically. Additional comments possible.
Carry-over review comment, SUB201900198: `(2/20/20, Revise cl) Revise oul de saes Reads r
4014t hang o f to 't (SJ ) t. 4 J G'
xxvuc ever -hang a �xxxsx�axxxcTvvTcx F}61c �e$}��3 d@li}C�e-M}�3. ru�}LDS—=rr.T�IVCW, Feb12, 2020 1:54 PM
email) Using a SU design vehicle then, there is option of: 45' R, which meets VDOT RDM B(1)-24 with
proposed Road D.1 / D.2 FC/FC street width =24'; or 30' R cul-de-sac with FC/FC street width =30'.
Either is acceptable. To provide neither would not meet AASHTO /VDOT RDM, or ACDSM
requirements. To provide one or the other also alleviates concern relating to parcel deliveries (ever more
common) and waste management access needs outlined in email sent 2/7/2020 8:48 AM (below).
Albemarle defers to VDOT /ACF&R should either impose requirement for radius > 30'. Road plan design
should accommodate whatever these review, transportation, and emergency response agencies require.'
RDM, Appendix B(1) Fig. 1
A single -unit (SU) truck design vehicle, as defined by AASHTO, should be used for
the design of all local subdivision streets. Dimensions for this vehicle are depicted
in Figure 2-2 of the AASHTO Geometric Design of Highways and Streets 2011,
shown as Figure 1.
E�
,d.
FIGURE 1 — "FIGURE 2-2" SCANNED FROM "A POLICY ON GEOMETRIC
DESIGN OF HIGHWAYS AND STREETS," AASHTO, 2011
Engineering Review Comments
Page 4 of 7
28. Provide details, plan labels (or both) for:
a. Knox box (Road F),
b. Bollards (Road F).
29. Label distance along Route 20 to nearest street intersection (both directions).
30. Provide curb extensions for parallel parking, Road B2; see design standard at VDOT RDM, B(1), pg. 59
(pg. 61 of .PDF /Link: https://www.virginiadot.org/business/resources/LocDes/RDM/AppendBl.vdf ).
F. Curb Extensions — Curb extensions at intersections are frequently used in
Traditional Neighborhood Developments. Curb Extensions are also used to
protect parking areas and to reduce pedestrian crossing times.
31
E m
m
E_ �
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V1 E
IF R Minimum
do
10' R Minimum
25' R Minimum
Effective Radius
40' Minimum —
Curb Extension (Bulb -Out)
C7/C8, Grading and Utility Plan: [SUB201900198 review. If addressed w/ ROAD plan, please disregardl:
a. (2/20/20, Revised) Engineering cannot recommend preliminm E�,,.,i plat . al of Y tin,
14DPE w / headw-all at Cow B -aneh Please provide additional design information for this
crossing; design for the 25-3r event. For perspective, please see photo d. 7/27/18 (by Albemarle),
below, which shows drainage structure beneath Rt. 20 upstream of proposed Road A.1 crossing.
tk4f1,\
d. Label . New: Label lots.
e. Note existing natural drainage that clips end of Road A2. Provide conveyance of storm runoff that
transits this natural drainage feature in the post -developed condition.
f. Avoid nuisance ponding on any private or public road; f r example in aircul r bulb portion of
Engineering Review Comments
Page 5 of 7
xvvxuc inlets a -ad piped drainage of runoff-, Road E. W1tI1dC`dR'll(em'al ,
2/6/20 642pm)
dwellings along Road E. StoFm r-unoff collection and conveyance applies to Road E. Also,
sommentselsewhe-re. Withd n (email, 2/6nO, &!2pn*.
i. Provide /show /label public drainage easement at NE corner Int. Road D and Road Al (Open
Space). Note: A portion of public drainage, Str. D3 — D1, lies outside public ROW.
j. D,-..vide /sho public .],- ;_ 0 o„ts eFossing rots 29 and 6 1.
k. Provide storm drain inlets at low point /sag, Road Al.
1. Remove entirety of proposed SWM facilities from stream -ward 50' of Cow Branch stream buffer.
m. Sh.,.,, ,,,-.,posed ..main Road F; utilize 1 ' design cont,.ws if neoessai
n. (2/20/20, Revised Provide design for Cow Branch crossing, Road F. Size pipe /culvert to pass the
25-yr event without overtopping Road F (Emergency Access). New: County email to Shawn
Maddox, ACF&R, 2/20/2020 11:07 AM requests guidance on ACF&R access needs relative to
existing pipe at stream crossing along dedicated fire -rescue access (2" d point of subdivision
access).
o. New: Relocate private waterline laterals outside public ROW, all lots.
p. New: Coordinate with USACE. Provide copy of Nationwide or Virginia General Permit to
perform construction in live stream (Cow Branch).
C9
32. Provide Class B — Type I primitive trail section (Ref. ZMA, sheet 9; image below).
33. Road Al profile: Label drainage structure dimensions /material type, INV elev., top of structure elevation
(at sag curve). Ensure adequate cover, given 10-'/2" pavement section, subgrade CBR requirement, and
apparent —I' distance between top of culvert and road finished grade. Cover appears inadequate.
34. Road Al profile: Show double -line culverts as two lines, not one line.
35. Road Al profile: Label drainage structures.
36. Show Road A2-Ex. Galaxie Farm Road transition. Provide grading /design that ensure smooth transition.
C10
37. Road B 1 /Road B2 include sag curves that do not meet Min. K value =15; provide Min. K-value. Also, ref
VDOT Road Design Manual, Appendix B(1), Table 1 reference to 2011 AASHTO Green Book. See also,
2011 AASHTO Green Book, Table 5-3. Albemarle may at times rely on 2001 AASHTO Guidelines for
Geometric Design of Very Low Volume Local Roads (ADT<400 ADT), which lists Min. rate of vertical
curvature for Crest Vertical Curves (Exhibit 12), and refences Ch. 5 of Green Book for sag curve Min. rate
of vertical curvature. Albemarle requires Min. K-values of 5 and 15 for crest and sag curves, respectively.
38. C12: Road D, Revise to provide Min. K-value /sag curve >15.
39. C13: Road F profile: Label drainage structure dimensions/material type, INV elevation, top of structure
elevation (at sag curve). Ensure adequate cover.
40. C15: Include VDOT CG-9D, Standard Entrance Gutter —Ref. 2016 VDOT R&B Standards, Rev. d. 07/15.
41. C18
a. Add SL-1 or''/2" steel plate labels to MHs, as needed (for example, Str. E7, which requires both).
b. Profile Al-A2: Provide wingwall design.
c. Ensure proposed culvert INV elevation comports with USACE countersinking requirements.
d. If culvert is a double line (B 1 — B2, for example), label profile for clarity ( dbl. line).
e. Revise profile F 1-F2 caption to read F 1-F4.
ZMA201800012 Sheet 7-related comments relating to SUB201900198 /ref. sheet 7 Notes, image below
42. Note 13: both 30'Aeeess Easement and ACSA water -line (publie utility) easements appeaF to extend 5'
within lots on west side of Read E, Lots 58 6 4, w4ile 30' Aeeess Easement ipA+udes 5' into Lots 62 65 an
east side of Road E. Note: No structures o i ' ; may occupy 20' ACSA easement, or- 30' A
easoment. Please consider- possible coniq vot At ;_imwe A-f- fiaWr-e building per-mit application. Recomme
propose no stfuettifal improvements within easements on pfeliminafy of final plat, or Road or W120 plans.
43. Note F: Remove lots from stream buffer. Also, item 18 4-5, above.
Engineering Review Comments
Page 6 of 7
44. Note G: Also, item 7 48, above.
45. Note KK� Also, item--' .
46. Also, please consider Albemarle County Engineer's comments on ZMA201800012, 9/23/19, which appear
relevant to preliminary plat, and subsequent plan applications, reprinted as text, below:
`Waiver Requests:
(1) Double Fronted Lots: No objection.
(2) Private Streets:
- Road D: The Design Standards Manual requires private streets to meet VDOT minimum standards,
however, the County has allowed by policy the use of ASHTO Geometric Design of Very Low Local
Roads for private streets with an ADT under 400 trips per day. If Block 1 is modified to serve only multi-
family (i.e. a site plan), standards may be reduced further as shown in the Design Standards Manual.
- Road E: Must also meet low volume road standards. Identify if any additional waivers are required.
(3) Private Street Design Requirements:
- Road D: Street must meet design standards noted above, unless serving multi -family only.
- Road E: Identify the purpose of the "bulb" on this road. Parking must meet County design requirements.
Has VDOT approved spacing requirements for public road intersections?
(4) Modification of Setbacks: No objection.
The road exhibits show a corner lot in Block 1, a few lots in Block 2, and the sidewalk in Block 2 within
the stream buffer. These improvements are not exempt and cannot be located in a stream buffer. This
comment was previously made during the ZMA review, which did not (does not) show these impacts.'
ZMA sheets (for reference)
Sheet 7, Notes
NOTES: v
A) For front loaded garages, the porch or building face shall be a minimum of 3 feet closer to the street as measured from the face of the garage door.
B) For those units that (1) do not front Roads A.2" or "B , and (2) are located in Block 2, utilizing Private Road "E", shall have a minimum front setback of 3 feet
from the right-of-way of Private Road "E". All other units shall have a minimum front setback of 5 feet, per Section 4.19 of the Zoning Ordinance.
C) All Blocks except 7 and 8 may be used for residential uses as noted by the unit types listed above.
D) All rear yards (except those adjoining Road "E") shall have a minimum setback of 20 feet.
E) Structures along Road "E" shall have a minimum rear setback of 5 feet.
F) No structures or lots shall be permitted in the stream buffer or on preserved slopes. No preserved slopes within the development shall be disturbed.
G) As applicable, retaining walls within the development shall meet the design standards required for the disturbance of managed slopes in Section 30.7.5 of the
Zoning Ordinance.
H) Total allowable residential units shall be 65.
I) Road "C" is shown as a possible future connection to Tax Map Parcel 91-13 to be extended and dedicated upon demand of the County.
J) Road "D. I" is shown as a possible future connection to Tax Map Parcel 91-10 to be extended and dedicated upon demand of the County.
K) 25% of the required stormwater quality treatment shall be provided onsite.
Sheet 8
1
All sections to comply with VDOT and/or Albemarle
County standards, as applicable
Engineering Review Comments
Page 7 of 7
Sheet 9
CLASS B - TYPE 1
PRIMITIVE NATURE TRAIL -Private
EASEMENT
5 - - --
CLASS B - TYPE 1
PRIMITIVE NATURE TRAIL
47. Calculation packet
a. Confirm that 10-yr event is design basis of LD-229, p. 13 of packet.
b. If so, please revise design of culverts to ensure pipe capacity > calculated peak discharge during
design event; for example, please examine and revise as needed design of.
i. G2 to GI
ii. F2 to F I (unless designed as detention pipe)
iii. E5 to E4
iv. E4 to E3
v. E3 to E2
vi. B2 to B 1
vii. A2 to Al
Please feel free to call if any questions.
Thank you. J. Anderson
434.296-5832 -x3069
SUB202000098 Galaxie Farm ROAD plan 071620