HomeMy WebLinkAboutSDP201000013 Review Comments Final Site Plan and Comps. 2010-03-30ALg�,��
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: Treesdale Park; WPO- 2010 - 00011; SDP - 2010 -00013
Plan preparer: Mr. Scott Collins, PE; Collins Engineering
Owner or rep.: Albemarle Housing Improvement Program, Inc.
Date received: 16 February 2010
(Rev. 1) 22 March 2010
Date of Comment: 8 March 2010
(Rev. 1) 30 March 2010
Engineer: Phil Custer
The second submittal of the final site and SWM plans for the Treesdale Park Project has been reviewed.
The following comments are provided.
A. SDP - 2010 -00013 Final Site Plan Comments
1. This final site plan shows more disturbance to critical slopes than the plan accompanying the
critical slopes waiver that was approved by the Planning Commission in the fall of last year.
Because of the increase in critical slope disturbance, it is my opinion that a critical slope waiver
must again be granted by the Planning Commission. This decision can be overturned by the Chief
of Current Development, who is the acting agent of the Zoning Ordinance for this project.
(Rev. 1) Engineering review has been verbally informed by the Chief of Current Development
that a critical slope waiver is not required at this time.
2. VDOT approval is required. At this time, VDOT approval has not yet been received.
(Rev. 1) The county has not received any confirmation from VDOT that the plan can be
approved.
3. An area for a bus stop, as required by Proffer 5, must be accounted for in this plan. This bus stop
will require the dedication of additional ROW in the future. The placement of Building 1 must
consider adjustment of the setbacks because of the future ROW dedication.
(Rev. 1) Comment has been addressed.
4. All Right of Way needed for this development on TMP 61 -184 must be dedicated before the
approval of this final site plan.
(Rev. 1) Comment has not been addressed. All public ROW necessary for the Rio Road
upgrades and construction of Stonewater Drive to Station 12 +00 must be dedicated prior to
approval of the Treesdale site plan. In addition, the private street easement for Stonewater
Lane, drainage easements, and temporary construction easements needed to complete all this
work must be provided by the owner of TMP 61 -184 before approval of the Treesdale site plan.
Please see comment B.I.
5. The construction and permanent (drainage and greenway) easements on TMP 61 -184 must be
recorded before this final site plan is approved.
(Rev. 1) Comment has not been addressed. The applicant has provided an amendment to the
agreement between Rio and AHIP, but this document only references a ]Oft construction
easement. Permanent greenway and public drainage easements are required prior to site plan
approval.
6. The construction and permanent easements on TMP 61A -A must be recorded before this final site
plan is approved.
(Rev. 1) If these easements are already recorded, please provide the Deedbook and Page
number within the set. (The offsite property in question is actually 61A -3 -A, not 61A -A.)
The boundary line adjustment combining all parcels into one must be recorded prior to approval of
this final site plan.
(Rev. 1) Engineering review understands this plat has already been approved and is currently in
the process of being recorded. Please provide the county with a receipt of recordation once the
plat is recorded at the courthouse.
Streams and wetlands are located within the limits of construction. Please provide an approval
letter from the Army Corps of Engineers. If the applicant contends that streams or wetlands will
not be impacted, please provide a letter from the Army Corps of Engineers that confirms this
statement.
(Rev. 1) Please remove the grading of the stormwater maintenance path from the wetland area.
Engineering will confirm that all ESC disturbances are outside of the jurisdictional areas once
the ESC plan is reviewed.
9. Please show all of the existing easements recorded with SUB - 2008 -00253 on the plat with the
deed book and page number listed. [18- 32.6.6]
(Rev. 1) Comment has been addressed.
10. Please add more TOW/BOW spot elevations on the retaining wall along Rio Road and remove the
note referencing a height of 7ft.
(Rev. 1) Comment has been addressed.
11. Please specify the two terminals of the guardrail along Rio Rd.
(Rev. 1) Comment has been addressed.
12. The layback angle of the segmental retaining wall used should be considered in the layout of the
site plan. For every 5.3 vertical feet, the wall loses Ift horizontally. For the series of walls on the
west side of the property, the lost space will likely not be an issue. However, the slope of the
retaining wall should be considered for the wall along Rio Rd. Please show the true thickness of
this wall, from the face at the bottom and from the back edge at the top. This will likely
necessitate moving the wall closer to the building in order to maintain the 2ft spacing between
back of wall and the guardrail posts as specified in the detail is sheet S -4.
(Rev. 1) The detail provided by the applicant on sheet S -5 does not match the dimension of the
design on Sheet S -1. Please modify Sheet S -1 to match the section detail. (For instance, the
ROW is shown as being 12.33ft off the back of curb in the detail, but on sheet S -1 it is shown as
]]ft. Also, the ]ft clearance provided from the ROW to the back wall segment on the detail
does not seem to be afforded on Sheet S -1.
13. For the wall along the Right of Way of Rio Road please provide a specific section detail
dimensioning the length of the geogrid system and show how the geogrid is built around the
guardrail. Please also show the ROW line in the section detail.
(Rev. 1) The detail provided by the applicant on sheet S -5 does not match the dimension of the
design on Sheet S -1. Please modify Sheet S -1 to match the section detail. (For instance, the
ROW is shown as being 12.33ft off the back of curb in the detail, but on sheet S -1 it is shown as
Ilft. Also, the ]ft clearance provided from the ROW to the back wall segment on the detail
does not seem to be afforded on Sheet S -1.
14. The guardrail along Rio Road should be maintained by VDOT. The retaining wall along the
ROW may need to be maintained by VDOT. Ultimately, the decision regarding maintenance of
the guardrail and wall will be made by VDOT. The applicant should be made aware that the
ROW line could need to be shifted farther into the site.
(Rev. 1) Since this comment letter was transmitted, VDOT has stated that the ROW should be
placed ]ft behind the back of the guardrail. Please refer to the previous comments.
15. All drainage pipes carrying water from the VDOT right of way must have drainage easements
dedicated to public use before the issuance of the first Certificate of Occupancy. The easements
dedicated to public use should be clearly differentiated from the other drainage easements shown
on the plan. The easements that must be dedicated to public use are over pipes 1, 2A, 2C, 3, 5, 7,
9, 11, 21, 23, 25, 27, 29, 31, and 33. Any portion of the drainage easements located on TMP 61-
184 must be recorded before site plan approval.
(Rev. 1) Drainage easements are not needed on the remainder of the pipes. If they are to
remain on the plan, please designate them separately from the public easements. The drainage
easement offsite must be recorded with a deed of easement prior to site plan approval.
16. Please provide a note on the cover sheet below the sheet index stating that the ROW dedication,
public drainage easements, and RWSA easement must be recorded prior to the issuance of the first
Certificate of Occupancy.
(Rev. 1) Comment has been addressed.
17. Please remove all significant trees from the public drainage easements.
(Rev. 1) All large trees have been removed from the public drainage. However, the easement is
now encompassing much of the retaining wall southwest of building 4. Please adjust the
easement so that the footer of the retaining wall is outside of the public drainage easement.
The pipe must be within the inner third of the easement, so it appears the pipe must be shifted
slightly as well.
18. The entrance has a slope steeper than 4% on the exit from the site. Please reduce this slope to 4%
or flatter.
(Rev. 1) Comment has been addressed.
19. The speed limit on this section of Rio Road is 35mph. For this reason, the sight distance triangles
must be adjusted.
(Rev. 1) Comment has not been addressed. The sight distance line looking south is still drawn
to 305ft as opposed to 390ft.
20. Please provide overland flow relief for inlets 12 and 16 so that structures will not be flooded in
case of inlet failure. [DM 18- 32.6.6.s]
(Rev. 1) Comment has been addressed.
21. Please show the crossing of a sewer lateral and fire line for drainage pipe 25.
(Rev. 1) Comment has been addressed.
22. In the calculations, a few of the pipes do not appear to be flowing under open channel flow
hydraulics. Please adjust the design of these pipes.
(Rev. 1) Comment has been addressed.
23. Please provide a channel design, with ditch lining, for the stream reconstruction after Pipe 3 is
placed.
(Rev. 1) A channel is still being disrupted with the storm sewer system installation and must be
replaced. A simple dimension callout and lining specification in the storm sewer profile will
suffice.
24. The drainage area map doesn't match up with the design of the roofdrain system. Please update
the map and calculations accordingly.
(Rev. 1) Comment has been addressed.
25. Many of the drainage areas in the plan that are >90% pavement should have a time of
concentration of 5 minutes. For instance, drainage areas for inlets 32 and 26 should have a time of
concentration of 5 minutes. Please update the map and calculations accordingly.
(Rev. 1) Comment has been addressed.
26. (Rev. 1) The ROW line north of the site entrance must be placed 1ft off of the sidewalk.
27. (Rev. 1) Please shift the easement over pipe 29 to the south so it does not encroach on the
building footprint.
28. (Rev. 1) Safety slabs are needed in structures 6 and 8.
B. SDP - 2010 -00013 Road Plan Comments
1. The barricade on Treesdale Way must be removed. Engineering review will not approve a plan for
this development that lacks safe movements from and onto northbound Rio Rd. In order to receive
engineering approval, Treesdale must either provide a full intersection on site (which may not be
allowed by Planning /Zoning because of the approved ZMA), construct the necessary road
improvements proposed in the Stonewater construction set, or wait until these improvements are
built or bonded by the Stonewater Developer before getting a Certificate of Occupancy. If the
applicant wishes to construct these improvements, the necessary road plans should be included in
this set and also accounted for in the Treesdale ESC plan. All necessary offsite easements and
ROW dedication must also be provided prior to site plan approval.
(Rev. 1) The last option listed in my comment above was incorrect. The certificate of
occupancy stage is not an appropriate time to confirm that all road improvements are
completed. The Treesdale site plan must show all necessary road improvements that must be
constructed in order for the site to be fully functional. Because the Right -In /Right -Out cannot
serve as the sole entrance for the project, the site plan must show all of the Rio Road
improvements shown in the Stonewater Plan as well as Stonewater Drive to Station 12 +00 and
Stonewater Lane to the property line. All ROW dedication and easements (access, drainage,
construction, etc.) must also be platted prior to Treesdale site plan approval.
2. The applicant has labeled the travelways within the plan as private roads. In looking through the
preliminary site plan file, it appears that these travelways were not approved as private roads. In
order to be referred to as a private road, please provide a request per 14 -234. The private roads
can be authorized by the Chief of Current Development. The appropriate road standards can also
be determined by the Chief of Current Development if approval of the road is granted. A technical
review of the road plans will be performed by engineering once the roads are authorized and the
standards determined. This request is not needed if the applicant changes all references to "private
roads" to "private access easements." Private access easements will be reviewed to the standards
outlined in 18 -4.12 and these standards appear to be met as designed.
(Rev. 1) Comment has been addressed.
3. In the Treesdale Way section, one of the sidewalks should be specified as 6ft wide.
(Rev. 1) Comment has not been addressed. Both Treesdale Way and Treesdale Park Court
should have one 6ft wide sidewalk in their section detail.
C. WPO- 2010 -00011 Stormwater Management Plan Comments
1. Per Water Protection Ordinance text amendments that were approved by the Board of Supervisors
last year, the WPO application for the Stonewater Development, WPO- 2007 - 00045, has been
voided because approval was given to the plans more than 12 months ago. Treesdale must include
all of the design graphics and calculations for the shared facility in this set for re- review. The
calculations should be updated with the latest proposed hydrologic information. (It looks as
though the drainage area to the BMP has gotten larger since the original design and the post -
development factored C calculation for Treesdale Park in the Stonewater set were incorrect.)
(Rev. 1) The water quality volumes and detention calculations are acceptable.
Please include the grading for the stormwater access and greenway path in the plan. Please
adjust the grading so that fill for the path is out of the wetland. This work will also need to be
considered in the erosion and sediment control plan for Treesdale.
2. Please include a modified simple spreadsheet for the SWM facility.
(Rev. 1) The Modified simple spreadsheet has been provided. Engineering recognizes that the
required removal rate is 53% but will permit the facility for this development to be an enhanced
extended detention basin since the proper volumes are provided.
3. Please specify the design of the concrete trash rack on the riser and provide a stage - discharge
graph so that routing calculations can be confirmed.
(Rev. 1) Comment has been addressed.
4. The pond shall not backwater into the drainage system. Please raise the outlet of the drainage
system to at least the permanent pool elevation.
(Rev. 1) Comment has been addressed.
5. Unless the design of the BMP is changing, please replace all references to an "enhanced biofilter
facility" to an "enhanced extended detention facility ".
(Rev. 1) Comment has been addressed.
6. Please provide a planting plan for the Extended Detention Facility.
(Rev. 1) The plants proposed in the landscaping plan are acceptable species. However, the
number of units appears to be short of general landscaping standards. Each planting should
be provided at 18" on center. In the plan, plants are shown between 3ft and 6ft away from one
another. Engineering review accepts that only half of the wetland area must be planted.
7. New Stormwater Facility Maintenance Agreements will be needed for both parcels 61 -183 and 61-
184. The new agreements should refer to the " Treesdale Park SWM Plan (WPO- 20 1 0 - 000 1 1)" on
page 1 of both documents.
(Rev. 1) Comment has not been addressed.
8. A new SWM bond will be computed once the WPO plan is ready for approval.
(Rev. 1) The SWM bond will be computed at a later date.
File: E2_fsp swm_PBC_wpo20100001 1- sdp201000013 Treesdale.doc