HomeMy WebLinkAboutSUB201600021 Approval - County 2016-07-22
County of Albemarle
Department of Community Development
Project: Old Trail Village Block 10, 16, 17, 18 & 30 –ROAD Plan
Plan preparer: Jim Taggart , Bill Ledbetter, Jeremy Fox –Roudabush, Gale & Assoc, Inc
914 Monticello Road, Charlottesville, VA 22902, bledbetter@roudabush.com,
jfox@roudabush.com, jtagg2@aol.com
Owner or rep.: March Mountain Properties LLC [1005 Heathercroft Circle, Suite 100]
Dave Brockman, dave@oldtrailvillage.com
Plan received date: 1 Feb 2016
(Rev. 1) 3 May 2016
(Rev. 2) 9 Jun 2016
(Final) 13 Jul 2016 (digital /.PDF –11:27 AM, A. George email /RGA)
Date of comments: 17 Mar 2016
(Rev. 1) 15 May 2016
(Rev. 2) 11 Jul 2016 (Conditionally approved: Final Approval requirements, see below)
(Rev. 2rev) 12 Jul 2016 –response to Applicant email, 7/12/2016 3:36 PM (ref. CV)
(Final) 22 Jul 2016 (County Internal reviewer email; 7/22/2016 12:22 PM) -Approved
Reviewer: John Anderson
SUB2016-00021 -Approved
Final Approval requires: (Rev. 2rev -12.Jul.16)
1. VDOT, ACSA Approval (Final) Addressed.
2. Alb. County Planning Div./ACF&R –“No objection”
a. Planning (6/23): Trees and sidewalks must be bonded with the road plans
b. ACF&R (7/7): Based on plans dated 6/8/16. No comments objections.
c. Ref. ACSA Approval Letters, 7/21/16; in RMS docs.
d. Ref. VDOT email, "No comments," -Adam Moore, 7/18/2016 8:32 AM (Also in RMS).X
3. Contact Plan reviewer to discuss review comments: 5, 20.e, and 23. Address. (Rev. 2rev) Partially
addressed. One Engineering review comment remains: #23 (Final) Addressed.
Ref. Ammy George email (7/13/2016 11:27 AM), w/3 plan-sheet Attachment
Blocks 10, 16, 17, 18 & 30 (block 30 Added with Rev. 1)
1. Sheet 1 –Revise index sheet 24 description to include ACSA Details. (Rev. 1) Addressed.
2. Sheets 6, 7, 8 –Reposition and add CG-12/curb ramps to face streets at perpendicular angle. This is a
recurrent VDOT comment (other projects). Please respond to VDOT comments on this ROAD Plan. (Rev.
1) Partially addressed. As follow-up: to extent practical, street crossing between opposing curb ramps
should be perpendicular to the street to minimize crossing distance, avoid potential pedestrian confusion,
and minimize pedestrian-vehicle conflicts. To extent practical, revise placement of opposing curb ramps,
particularly at: Golf Drive/Fielding Run, Golf/Rowcross St, Upland Drive/Fielding Run, and Highgate
Row/Upland Drive intersections. (Rev. 2) Addressed.
3. All sheets –Please reference SDP201600006 and WPO201600009 preview comments. Revise ROAD Plan
as needed. (Rev. 1) Acknowledged.
4. Sheet 7 –Add stop sign label, Bayward St./Rowcross St. (Rev. 1) Addressed.
Engineering Review Comments
Page 2 of 4
5. Sheet 12 –Revise design; replace three (3) existing storm pipes. Run-off (CFS) exceeds pipe capacity:
(Rev. 1) Not addressed. 3 May 2016 Applicant response: “We [RGA] are preparing a comprehensive
analysis of the existing storm sewer system that drains to this area. There appears to be a difference
between what was planned and what was built. This analysis will follow under a separate cover.”
a. Ex. 9-14 to 9-12
b. Ex. 9-12 to 2-18
c. Ex. 2-18 to 2-16
(Rev. 2) Partially addressed –As follow-up, in response to J. Taggart email (6/27/2016 10:59
AM) stating in part: “Even though we are adding only four inlets and one manhole to this system,
we performed a fairly exhaustive model which included the other 71 inlets. This is the only way to
properly evaluate the true need for systemic upgrades. Our model clearly indicates the
containment of the 10 year hydraulic gradeline well within the system indicating our capacity is
adequate. I believe the recently submitted calculation package demonstrates this situation *,”
please accept that the first drainage comp checklist item in Engineering review is to ensure that all
[pipes] are designed within open channel flow capacities. Please confirm that pipes listed at a,b,c,
above, are within open channel capacities (HGL computation are not necessary, and should not be
relied upon unless the entire system is to be watertight.) Although 6/27 references calculation
package, neither 8-Jun submittal nor 5-Jul .PDF Attachment appear to include pipes listed at a,b,c,
above. Rather, this table Note (p. 2, STORM SEWER DOT REPORT): “These inlets connect to an
existing system at Existing Structure No. 9-12”. This is the extent of reference to existing pipes.
Please provide analysis that ensures all pipes are designed within open channel flow capacities, or,
as an alternative, appeal review comment to County Engineer, and request unconditional ROAD
Plan approval. At this point, reviewer cannot confirm existing pipes which will receive additional
runoff with this design conform with review checklist –comment persists from 17-Mar review. If
existing pipes cannot operate within open channel flow capacities, recommend examine options,
including Ex. pipe replacement. Image below: checklist. Checklist also attached to comments.
[* italics /emphasis added] (Rev. 2rev) Addressed.
(Rev. 1) As follow-up: Run-off (CFS) exceeds pipe capacity at additional location (ref. storm sewer
design table, 5/3/2016:
d. Point 16 to 15: Revise design. (Rev. 2) Addressed.
6. Sheets 12, 13, 14 –Label pipe structures, plan view (Assign IDs). (Rev. 1) Partially addressed. As follow-
up:
a. Label structures between inlets 15 and 17 (2 pipes; 1 MH) (Rev. 2) Addressed.
b. Label pipe #s 52, 54, 56, 58 (sheet 12); 79 (sheet 13). (Rev. 2) Addressed.
7. Sheet 14 –Revise pipe DIA between inlet 123 and 121; run-off CFS exceeds pipe capacity. (Rev. 1)
Addressed.
8. Sheet 16 –Provide landing /Sta. 10+11.75 – 10+51.75, Aldersgate Rd -40-ft. at 2.08 4% or less (can be
within first road/vertical curve). (Rev. 1) Addressed.
street grade is less than 4% for a minimum of 40’ from the edge of pavement of the intersected street. (This grade
can be within the first road curve which transitions from the 2% intersected cross grade) {policy, follows ord. for
travelways 18-4.12} (ROAD Plan review checklist)
9. Sheet 16 – Provide VC transition: -2.08% to -1.54%, Beechen Lane. (Rev. 1) Addressed.
10. Sheets 16-19/CD-1 (Rev. 1) Addressed, except as noted (d.)
a. Shift CD-1 to proposed/existing grade point of intersection. At one location, 50’ away.
b. Provide CD-1 at every vertical sag curve.
c. Provide CD-1 at every proposed/existing grade intersection.
d. As follow-up: provide CD-1 at Upland Drive, Sta. 23+50±. (Rev. 2) Addressed.
11. Sheets 16-19/inlets –Revise inlets shown above/below proposed grade. (Rev . 1) Addressed.
12. Sheet 17/Petyward Lane –Provide stationing along horizontal axis (profile). (Rev. 1) Addressed.
13. Sheet 18 –Provide tangent or vertical curve data @ begin construction, Rowcross St. (Rev. 1) Addressed.
14. Sheet 19 –Recommend revise 0.50 and 0.51% slope storm drains –ref. storm sewer schedule. (Rev. 1)
Withdrawn (review checklist explicitly states minimum slope for a storm pipe). Please see Drainage Plan
review checklist: item 3, pg. 2 (slopes at 0.5% min. to 16% max. (per VDOT stnds for anchors over 16%)).
15. Sheets 20, 21 –Revise inlets shown above/below proposed grade. (Rev. 1) Addressed.
16. Sheet 20 –Storm Sewer Profile #53-#59: Show existing grade. (Rev. 1) Addressed.
Engineering Review Comments
Page 3 of 4
17. Sheet 21 –Revise storm sewer notes which seem to blend step, safety slab, and inlet shaping notes. (Rev. 1)
Addressed.
New (Rev. 1)
18. Minor text edit –Check spelling of Aldersgate Row across plan sheets. (Rev. 2) Addressed. Applicant
comment response d. 8-Jun: “Road spelling has been confirmed as Adlersgate Row”
19. Sheet 8 –Provide horizontal geometry for Rowcross Street EP-EP transition from 26’ to 32’ width. (Rev. 2)
Withdrawn. Discussed with RGA week of 7/4.
20. Sheets 9, 10, 11 (storm drain design) –Also see 4”/6.5” inlet design sheets (Also: 14-410.G., Drainage)
Note: county requires and recommends a more conservative design.
Revise design to:
a. Provide L/Lt >1.0 at inlets 103, 105, 107, 111 (3 of 4 inlets located on inside of 110’ R 20 mph
curve). (Rev. 2) Addressed. Column (L/Lt) was apparently removed from Storm Sewer Design
Calc. Inlet Report, but spread at inlets 103, 105, 107, 109, 111 and 117 are ≤8.55’ (gutter pan [2’]
+ ½ travel lane width). Rowcross St. (where all listed inlets located) varies 26’–32’ EP/EP.
b. 36 inlet structures are 2’ or 2.5’ in length. This represents significant departure from past, more
conservative Old Trail Village ROAD Plan storm drain design/s. Provide design rationale for
carryover at every single non-sag inlet. Carryover should be a design exception, not the rule.
Carryover at every inlet during a 6” in/hr. event worsens in every less frequent storm event. (Rev.
2) Addressed. Although difference in preference for conservative design persists, addressed.
Also, ref. c., immediately below.
c. Eliminate carryover at Inlets 43, 59, 66, 68, 90 (locations not arbitrary; evaluated against grade).
Carryover at these locations strands water below each inlet, where it pools. (Rev. 2) Addressed.
Carryover eliminated at all but one listed inlet (inlet 43), where carryover /bypass =0.98 cfs.
d. Provide spot elevations to guide construction at Inlets 123, 125, 129, 133, 135, 137. (Rev. 2)
Withdrawn –Ref. storm sewer profiles.
e. Revise inlets to ensure gutter depth ≤ 1.5” (0.125’) on private streets with roll top curb. This
requires conservative evaluation of inlets on Aldersgate Row, Beechen Lane, Petyward Lane, and
Priory Terrace. Note, for example, inlets 11, 84, 86, 92, 94, and 96—all located on roll top section
streets with gutter depth >1.5” (at inlet). Despite transition to CG -6 at inlets, there is unknown
effect through roll-top sections prior to CG-6 transition. 2” roll top (ht.) vs. 6” CG-6 suggests
impact to multiple dwellings under current design. A 25-yr event will have an even worse effect.
(Rev. 2) Partially addressed. Ref. roll-top detail, sheet 25: 2” depth (0.1667’) overtops curb.
Although depth at inlets 11, 84, 92, 94 is reduced if compare 7/5 .PDF with 8-Jun Inlet Report, at
none of the six listed inlets (11, 84, 86, 92, 94, 96) is depth <0.1667’. Please call to discuss.
(Rev. 2rev) Telecon w/Applicant 12-Jul. Review error. Capacity /runoff depth roll-top gutter
=4” (0.33’). Also, ref. Applicant email: 7/12/2016 3:36 PM. Comment withdrawn.
f. Identify inlet 5 as a sag inlet. Provide spread (4 in/hr.) at inlet 5. (Rev. 2) Addressed.
g. Reduce spread at inlets 109 and 117. This request is supported by 14-410.G –text image, below.
(Spread at these inlets should reduce with design revision requested at a., above.) (Rev. 2)
Addressed.
h. Limit spread, inlet 68. Permissible spread for Upland Drive =2’ + ½ travel lane width, or 2’ +
.5(13’), or 8.5’. Design proposes 9.46’ spread. (Rev. 2) Addressed.
14-410.G.
21. Sheet 18 –Minor: Match line with sheet 19 splits VC data. Show entire VC data on either sheet 18 or 19.
(Rev. 2) Addressed.
22. Sheet 32 –Recommend revise block 10 plant list table title to include ref. to block 30 in title as well, if true.
(Rev. 2) Addressed.
New (Rev. 2) (Rev. 2rev)
Engineering Review Comments
Page 4 of 4
23. Sheets 6, 7, 8: Provide curb cuts for SWM Facility Maintenance Access (L-3, S-3, S-12) consistent with
6/28/16 Stantec SWM Plan for SWM facilities for blocks 10, 16, 17, 18 and 30. (Final) Addressed. Ref.
Ammy George email (7/13/2016 11:27 AM), w/3 plan-sheet Attachment
Please call 434.872-4501 –x3069 if any questions.
Thank you
File: SUB201600021-Old Trail Village blocks_10,16,17,18&30_RP_072216ja-Approval_061518.doc