HomeMy WebLinkAboutSDP200900010 Review Comments 2007-12-12off
COUN'CY OF ALBENIARLE
Department of Community Development
401 Jlclntire Road
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 - Fax (434) 972-4126
Project: SD1:1-2006-00131, City of Charlottesville CTS Operations Center
WP( )-2007-00091, City of CharlottesviIIe CTS Operations (`enter
Plan preparer: Mr. Steve Davis, AIA far: 434.296.4496
VMDO ;architects
Owner or rep.: City of Charlottesville lax: 434.970.3817
Date received: 24 October 2007 (plait rev. date j2 October 2007)
Date of Comment: 12 December 2007
Engineer: Phil Custer
The major amendment for the City of Charlottesville CTS Operations Center, received on 24 October
2007, has been reviewed. The engineering review for current development cannot recon-inlcnd approval to
the plan at this tulle. Please revise and resubmit atter the following comments have been addressed.
Frigineering review is available from 2-4PM on Thursdays to discuss any of these comments. To schedule
a meeting or if you have any questions, please feel free to contact me at 296-5432 x3072.
A. General review comments:
1. The site plan submission must include a signed and dated professional seal. [DTVI]
2. Please note that there is no existing WPO buffer along the tributary to Moore's creek on T'MP
71 F1 -01. If the applicant wishes to propose a buffer, please indicate clearly oil the plan.
3. A temporary construction easeinent is required on TMP 771:1-1 D for the (Trading necessary to
construct the improvements on Avon Street Extended.
4. The front Section 14-4-12.16 has not been granted. Justification MUst be `:11ven to
Convince the Luning Administrator that "tile public health, safety or welfare would be equally
lir better served by the modification or waiver and that the modification of walVCr would not
otherwise be contrary to the purpose and intent of [Chapter 18-4]."
J. Site plan approval cannot be `,ranted until all of VDO1 's concerns and comments have been
addressed. VDOT comments will be forwarded once we receive them.
6. For all re, icw sections below, additional conlnlents play be forthconling on the next submittal.
B. Site Plan comments:
7. Please label the floodplain with the FE:VI.V map number and date. [DM]
S. file I00 -year floodplain sho,vn on the existing conditions page (tiles not appear to snatch the
latest FEMA map. Please correct. [D%1]
9. Not all critical slopes are hatched on the existing conditions sheet. Please show all slopes that
are greater than 25° o. [32.5.6d]
10. The travelway in the parking lot must ha, c a Width of 24ft if parking spaces of less than l Oct
width are pro, ided. [-4.12.16c. I ]
11. Please provide more labels on the site plan indicating the types of curbing used. [DISI]
12. In locations where curbing is proposed, please show two lines to demonstrate its width.
Sidewalks widths do not include the width of the curb. The applicant play ha, e to adjust the
dimensioning in some areas if bumper blocks are to be avoided. [DTVI]
13. The width ofi. ; . arallel parking spaces must be 9ft. [4.12. L_ -]
14. Please show sight distance triangles onto VDOT ROW. [DNI]
15. The nlininlum length of a loading space is 2511. [4.12.18a]
16. The nlaximunl grade for parking spaces, loading spaces, and access aisles abutting parking or
leading spaces shall not exceed five percent in any direction. [4.12.1 5c]
17. There appears to be proposed slopes steeper than 2:1 on site. Please correct. [D%I]
IS. Please prop ide an adequate landing all new entrances on the site. "As a guideline, the
approach grade should not exceed four percent filr a distance of not less than forty feet
nicasurcd train the edge of tile street being intersected." Please also include the VDOT
entrance designation on tlie grading sheet [4.12.17b]
19. On sheets. S-1 and S-2 Type C pavement in the VDOT ROW was labeled as " Turf block
20. Parallel parking spaces will not be permitted on Rion Street Extended.
21. There scenes to he no overland flow relief if strictures S-2 and S-1 become clogged. Please
correct. [I)NII
22. Site runoff must not drain into strects. Please correct grading and drainage strictures around
elle southern entrance to fix this problem. [DNI]
23. All slopes steeper than 3:1 must have ]ow maintenance; grotulcicovcr specified. [DNI]
�4. Please show inlet shaping (IS -1 ) on all inlets and in all manholes that do not already have
scour protection. [DiLI]
'5. Contour lines that are perpendicular to the centerline of the travelway will not be permitted.
Please either crown or slope to one gutter. [DNI]
26. Show and dimension riprap outlet protection on the plan per calculations. [DNI]
27. Is existing stoitmvater stricture #7 to he demolished'.' If so, please remove from development
plans.
28. "rile inverts of structure 1-5 do not match between the profiles and calculation. [DSI]
29. Please draw inlets so that they represent the correct dimensions. [DTVI]
30. In table 7, some of the throat lengths do not match between columns 3 and 25. [DTVI]
C. Stormwater Management review comments:
31. Engineering reg iew will consider the ruotdrain collection and resupply systCIIls private and not
subject to the normal requirements of our design manual. However, the downstream drainage
system should be designed assuming that the cistern overflows for all design storm and
provides no detention at all.
32. Engineering revictiv, will give quality credit for the use of the cistern if it is sized to capture the
hater quality volume for tele all the buildings. Please prop ide this calculation and a simple
detail of the cistern showing its dimensions.
33. Drainage area lines appear to be incorrect in smile places. Please correct. Drainage area lines
should not stop at property lines in analysis. f0 perforin all accurate analysis, the applicant
may need to use a different scale to pro% idc a fuller \ iew of the development and the
surrounding points of analysis 1101- the drainage area maps.
34. It appears that the: rcinoval rate provided In S� NI faeifities =2 and #-I are iIWdegLIatC fur the
drainage area. Please correct. [VSNIH, Dtill
35. It appears that no storimvater trcatnIC1It will Occur in the underground facility. Please prop ide
treatment in this area. If Infiltration credit is soLlght, the applicant must supply soil tests
verifying that the soil is adequate to use an infiltration measure. Generally, the soils fouled in
this region do not allow for infiltration to he used with any degree of confidence. [D%I]
36. Detention calculations appear to be missing. Please route all detention strictures to shoe- that
al] detention requirements are islet. [DNI]
3 7. It is unclear how any detention is provided on site. Please prop ide greater details on the outlet
control strictures for all detention facilities. See above coinmcrit.
38. Sediment forebays are required on all water quality facilities that receive concentrated flow.
Please deign each forebay to the standard :in the VirgiIiia Storni Vater I`VIanagCincilt
Handbook. [VSMI-H]
39. It appears that _;elopment of this site will demolish the ex. —..lg storin),vater management
Facility and replace it with a new one. If this is the case, the pre -development analysis should
assume an undeveloped site because the site is currently detaininu water to meet the initial
pre -development rate.
40. Please include the planting plan filr each biofilter in the stornnvater section of the plan set.
Fach biotilter detail Should have its own planting schedule. [D` /1]
41. Please provide sizing calculation tilr each biotilter. [DM]
42. Please label nuninlum bed dimensions in each biotilter. [Dtit]
43. Fach biotilter shall specify 3 species of tree and 3 species of shrub.
44. Please provide a typical section for cacti biotilter. [DNI]
45. Please submit a stornnvater facility maintenance agreement and fee to the county. [DM]
46. Please encompass all SWNI facilities ill an casement (including the cistern). [D,O]
47. Please remove the fire hydrant frons within SWNI facility "I .
-IS. Engineering revic"v does not recommend the use of CHIP detention structures.
D. Erosion and sediment control comments:
49. Please include a detailed construction sequence in the erosion and sediment control narratille.
[VESCH]
50. The under round detention structure can not conte online until the site has been deemed
stabilized by the county erosion and sediment control inspector. Please include tills note on
the plan and demonstrate how the facility is to he constructed without being clogged. [Diel]
51. The drainage area to sediment trap ? is greater than 3 acres. A sccliment basin is needed at this
location. [VESCII]
52. Please show tree protection fencing oil the plan per standard 3.08 in the VESCH or remove
from plan if not needed for other agency requirements. For example, the fencing must be
placed 511t outside of the dripline of the tree. Also, it appears that in some locations, drainage
strictures, silt fence placement, and grading will interfere with tree protection Iencing and May
compromise the health of the tree.
I. Please provide a staging area on site. [DM]
54. Please show the demolition to the curb island in the adjacent parcel within the limits of
construct loll.
55. It appears the drive aisle down to the, tion stockpile is not protected with any FSC measures.
Please address. [VF.SCI l]
56. FSC measures appear to be in the way of site grading between phases I and ?.
57. Construction traffic shall only ether and exit the limits of disturbance through the approved
construction entrance. Please show a barricade in the locations where construction traffic may
be likely to leave the site without using the approved construction entrance. [VI:SCI I]
5S. Existing structure I I needs sonic titan of protection. It appears that for both structures in this
vicinity, a cul\crt inlet sediment trap is the Most reasonable pleasure to be used. [VESCIi]
59. File northern property line is not adequately protected. Please address. [VF.SCI I]
60. I'he ESC protection at the northern site entrance will need to be amended. I he silt fence
tllroLlgll pave111el1t in this area will be all inadequate ESC measure. [VFSCH]
01
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�IRGIN1P
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Project: SDP -2006-00131, City of Charlottesville CTS Operations Center
WPO -2007-00091, City of Charlottesville CTS Operations Center
Plan preparer: Steve Davis, VMDO [email: davis(d)vmdo.com]
Owner or rep.: Scott Hendrix, Charlottesville [email: hendrix(a)charlottesville.or_�]
Date received: 24 October 2007 (plan rev. date 22 October 2007)
20 Mar 2008 (Revl)
Date of Comment: 12 December 2007
28 Apr 2008 (Revl)
Engineer: Phil Custer
Jonathan Sharp (Reel) [phone: 566-2578]
Engineering cannot recommend approval to the final major amendment for the City of Charlottesville CTS
Operations Center until the following comments have been addressed.
A. General review comments:
3. A temporary construction easement is required on TMP 77E1-1 D for the grading necessary to
construct the improvements on Avon Street Extended.
Rev]: comments not addressed At a minimum, temporary construction easements can be
handled by a letter of intent by the owner of the parcel. If a formal easement is pursed, it
must be recorded prior to site plan approval.
5. Site plan approval cannot be granted until all of VDOT's concerns and comments have been
addressed. VDOT comments will be forwarded once we receive them.
Rev]: VDOT approval is required A copy of the plans has been submitted to VDOT for
review.
6. For all review sections below, additional comments may be forthcoming on the next submittal.
Rev]: See additional comments throughout the comment response letter.
B. Site Plan comments:
latest FEMA map.1'lease correct. [DM]
Rev]: comments addressed.
9. Not all critical slopes are hatched on the existing conditions sheet. Please show all slopes that
are greater than 25%. [32.5.6d]
Rev1: comments addressed.
10. The travelway in the parking lot must have a width of 24ft if parking spaces of less than 1 Oft
width are provided. [4.1 2.16c.1]
Rev]: comments addressed.
11. Please provide more labels on the site plan indicating the types of curbing used. [DM]
Rev]: comments addressed.
12. In locations where curbing is proposed, please show two lines to demonstrate its width.
Sidewalks widths do not include the width of the curb. The applicant may have to adjust the
dimensioning in some areas if bumper blocks are to be avoided. [DM]
Rev]: The following in regards to parking areas must be revised:
a. In the parking area adjacent to the CTS operations building, the space directly
opposite the last fuel efficient vehicle space is only 14.47feet in length because part of
the space extends into the adjacent travelway (travelway measuring 22.73 ft in width).
Please reconfigure this part of the parking area so that spaces are a minimum of 16
feet in length.
need 5 b. Curbing is required for the parking spaces directly adjacent to the CTS maintenance
C V r b n building. The width required for the curbing cannot be included in the 6 feet width
needed for the sidewalk.
9 V e 1 Arf.,A e. Parking spaces directly adjacent to the CTS maintenance building must be 18 feet in
v\A '51&000t< length.
d. The travelway adjacent to the CTS maintenance building is labeled as 26 feet in width
and the adjacent parking spaces opposite the building are labeled 16 feet in length,
when they should be labeled 24 feet and 18 feet, respectively. Please correct this
13. The width of all parallel parking spaces must be 9ft. [4.12.16c.2]
Rev]: The travelway adjacent to the parallel parking should be 2 way in circulation and a
minimum of 20 feet wide.
14. Please show sight distance triangles onto VDOT ROW. [DM]
Rev]: comments addressed.
15. The minimum length of a loading space is 25ft. [4.12.18a]
Rev]: comments addressed.
16. The maximum grade for parking spaces, loading spaces, and access aisles abutting parking or
loading spaces shall not exceed five percent in any direction. [4.12.15c]
Rev1: The employee parking area adjacent to the CTS maintenance building between
elevations 435 and 441 is at a slope of 5.2%. Please revise to a maximum of 5% in slope.
17. There appears to be proposed slopes steeper than 2:1 on site. Please correct. [DM]
Rev]: comments addressed.
18. Please provide an adequate landing all new entrances on the site. "As a guideline, the
approach grade should not exceed four percent for a distance of not less than forty feet
measured from the edge of the street being intersected." Please also include the VDOT
entrance designation on the grading sheet. [4.12.17b]
Rev]: The entrance to Avon Street adjacent to building D is shown at 5.4% in slope. Please
revise to a maximum of 4% slope for a distance of 40 feet.
19. On sheets, S-1 and S-2 Type C pavement in the VDOT ROW was labeled as "Turf block".
Rev]: comments addressed.
20. Parallel parking spaces will not be permitted on Avon Street Extended.
Revl: comments addressed.
21. There seems to be no overland flow relief if structures 8-2 and 8-1 become clogged. Please
correct. [DM]
Rev1: comments addressed.
22. Site runoff must norain into streets. Please correct grading and drainage structures around
the southern entrance to fix this problem. [DM]
Rev]: comments addressed.
23. All slopes steeper than 3:1 must have low maintenance groundcover specified. [DM]
Rev]: Low maintenance ground cover cannot be any type of grass.
4. Please show inlet shaping QS -I) on all inlets and in all manholes that do not already have
scour protection. [DM]
Rev]: comments addressed.
25. Contour lines that are perpendicular to the centerline of the travelway will not be permitted.
Please either crown or slope to one gutter. [DM]
Rev]: comments addressed.
26. Show and dimension riprap outlet protection on the plan per calculations. [DM]
Rev]: comments addressed.
27. Is existing stonnwater structure #7 to be demolished? If so, please remove from development
plans.
Rev1: comments addressed.
28. The inverts of structure 1-5 do not match between the profiles and calculation. [DM]
Rev]: comments addressed.
29. Please draw inlets so that they represent the correct dimensions. [DM]
Rev]: comments addressed.
30. In table 7, some of the throat lengths do not match between columns 3 and 25. [DM]
Rev]: comments addressed.
Additional Comments:
9rmve 1 UrPG : ---a a) All sidewalks must be concrete, not gravel. [per DM]
n st�ewall� b) I cannot find drainage area maps that correspond to the inlets. There should be
drainage area maps separate from the SWM drainage area maps, showing the
drainage going to each inlet. The SWM drainage area maps are confusing. Some of
the drainage areas do not correspond the actual areas draining to inlet. The
drainage areas shown for drainage structures along Avon Street do not include
ROW drainage, and do not match the drainage calculations. Several drainage areas
along Avon Street are missing. Please provide separate drainage area maps for the
drainage plan, with drainage areas corresponding to each inlet. The destination
structure of the drainage areas should be labeled for each drainage area. Also,
showing drainage pipes and structures on the drainage area map is helpful.
c) There appears to be an existing structure with endwall very close to line S-5 to 5-13.
The plans do not indicate if this structure will be removed. Please clarify.
d) Portions of proposed improvements are missing on the grading plans (5-3,4) near
the northern entrance. Please include all proposed improvements on the grading
plans.
e) The drainage concept for the proposed cistern system is confusing. It appears that
roof runoff will drain to a large cistern in the CTS maintenance building. Will the
system be able to collect the first 1 inch of runoff for water quality volume
requirements? Please show that this volume will make it into the cistern, and will not
spill over the roof or gutters. Only this volume needs to be conveyed to the cistern
for water quality purposes Overflows can be provided at each building for larger
storm events so the large storm events do not pass through the cistern system. If
larger storms are not conveyed through the cistern (such as the 2 and 10 year
storm), identify which drainage structures convey the runoff and size the
structures/facilities appropriately to handle the additional runoff.
f) Please provide pipe profiles and calculations for the bus canopy drainage system.
g) There is a concern with the outfall of the proposed SWM facility #5. The outfall
appears to flow through a waste area, and there is a concern with sedimentation and
erosion in this area. Please provide a plan which will ensure the runoff from outfall
of the facility will not flow through the waste area.
h) Please analyze the existing drainage systems that the site ties into (structures 6-7, S-
13, and the DI below 4-8) to ensure that adequate downstream pipes/channels are
provided all the way to Moore's Creek. [MS -19]
C. Stormwater Management review comments:
31. Engineering review will consider the roofdrain collection and resupply systems private and not
subject to the normal requirements of our design manual. However, the downstream drainage
system should be designed assuming that the cistern overflows for all design storm and
provides no detention at all.
Revl: Additional information is needed for the cistern system. See comments about
drainage in the additional comment aQ under the site plan comments and comment 32
below. It appears that the cistern is still being used for detention.
32. Engineering review will give quality credit for the use of the cistern if it is sized to capture the
water quality volume for the all the buildings. Please provide this calculation and a simple
detail of the cistern showing its dimensions.
Rev]: Please provide a detail of the cistern in fire SWM plans. Our water quality
requirements are based on volume. The first I inch of runoff must be able to be collected
within the cistern. Please show that the first 1 inch of runoff will make it into the cistern
(not overflow over the gutter system on the roofs of buildings) and that the cistern can /told
the volume of the first I inch of runoff in addition to an average storage volume of water in
the tank for between storms. Will the water in the tank be used up very quickly? Please
calculate an average volume of water that will be stored in the cistern based ori water usage
so that if a storm event occurs the entire 1 inch of runoff will be treaded and will not
overflow from the cistern.
33. Drainage area lines appear to be incorrect in some places. Please correct. Drainage area lines
should not stop at property lines in analysis. To perform an accurate analysis, the applicant
may need to use a different scale to provide a fuller view of the development and the
surrounding points of analysis for the drainage area maps.
Revl: comments not addressed. Drainage area maps for stormwaater detention should
include all areas draining to analysis points, facilities, or structures. Please show the area
draining to each facility. Sub -areas draining to inlets should not be shown, only areas
drainage to each facility. In the case of facilities in series, it is usually easier to provide 2
sets of drainage area maps: 1 set showing the drainage areas draining to BMPs, and
another showing drainage areas to detention facilities.
34. It appears that the removal rate provided in SWM facilities #2 and #4 are inadequate for the
drainage area. Please correct. [VSMH, DM]
Revl: Water quality drainage areas should not include offsite drainage areas when
calculating removal rates. SWMfacility #2 includes offsite area. When done correctly, the
removal rates for facility #2 becomes 65%. Also, in the water quality compliance table, the
removal rate for SWM #4 is listed as 100%, when it should be listed as 65% (removal rate
of an infiltration trench).
35. It appears that no stormwater treatment will occur in the underground facility. Please provide
treatment in this area. If infiltration credit is sought, the applicant must supply soil tests
verifying that the soil is adequate to use an infiltration measure. Generally, the soils found in
this region do not allow for infiltration to be used with any degree of confidence. [DM]
Rev]: The underground facility should be designed as an Infiltration Trench (VSMH 3.10).
Our water quality requirements are based on volume. In order to achieve a 65% removal
rate, the facility must be sized to infiltrate the first 1 inch of runoff. The volume used for
infiltration should not be included in the storage volume for detention. For example, if 220
cu yd are needed for water quality volume and this volume is located at elevation 438, then
storage for detention routing should begin at elevation 438.
36. Detention calculations appear to be missing. Please route all detention structures to show that
all detention requirements are met. [DM] ..-
Rev]: The detention calculations are very confusing. The narrative states that only the
underground facility will be utilized for detention, when it appears on the detention
compliance table all the facilities are being used for detention. The compliance table shows
that the 10 year storm is not met for the rational method. The rational method should be
used for drainage areas of the small size found on site. The detention compliance table is
very confusing. Areas not draining to the underground facility are being treated as if they
are being routed through the facility. Please show the total drainage draining to each
facility (as the facilities are in series and downstream facilities capture drainage from
upstream facilities). There is not enough information provided to verify whether or not
detention is met. Calculations should include all outlet structure information. Typically the
downstream most facilities are designed and sized to handle stormwater detention, and
upstream facilities serve only as water qualityfacilities. There are too many questions and
concerns to discuss in a comment letter. Please contact Engineering to discuss how
stormwater detention is handled and consult the County Design Manual. Engineering is
available for meetings every Thursday from 2:30 to 4: 06pm. Please call to schedule a
meeting.
37. It is unclear how any detention is provided on site. Please provide greater details on the outlet
control structures for all detention facilities. See above comment.
Rev]: Stormwater facility outlet structure information should be located on the SWM plan
sheet included with the cross sections for each facility. See comment #44.
38. Sediment forebays are required on all water quality facilities that receive concentrated flow.
Please design each forebay to the standard in the Virginia Stormwater Management
Handbook. [VSMH]
Rev]: Forebays are needed for SWM facilities #1 and #2.
39. It appears that development of this site will demolish the existing stormwater management
facility and replace it with a new one. If this is the case, the pre -development analysis should
assume an undeveloped site because the site is currently detaining water to meet the initial
pre -development rate.
Rev]: comments addressed.
40. Please include the planting plan for each biofilter in the stormwater section of the plan set.
Each biofilter detail should have its own planting schedule. [DM]
Rev]: comments addressed.
OK cyc�5 41. Please provide sizing calculation for each biofilter. [DM]
>, d �•l v cu lc s Rev]: Biofilter sizing calculations are based on surface area, not volume. Biofilter floors
V 4� ' i y% should be sized for 2.5% of the impervious area draining to the facilityfor a 50% removal
rate requirement, and 4% of the impervious area draining to the facilityfor a 65% removal
rate requirement.
42. Please label minimum bed dimensions in each biofilter. [DM]
Rev1: comments addressed.
43. Each biofilter shall specify 3 species of tree and 3 species of shrub. [VSMH, DM]
Revl: comments rr_ddresse(1
44. Please provide a typical section for each biofilter. [DM]
Rev]: Cross-sections are needed for each biofilter including the following information and
meeting the following criteria (directly from Design Manual):
Embankments (between 3 and 25 ft in height)
a) top width 8ft min., 10' for heights 15' to 20', 12' for dams over 20', heights
measured from the outside toe
b) upstream face slope 2:1 or flatter, labeled
c) downstream slope 3:1 or flatter, labeled
d) 10yr and 100yr high water elevations labeled with 1 ft freeboard for 100yr
storm with emergency spillway or 2 ft freeboard without emergency spillway
e) an impervious core
f) a cutoff trench of minimum 4' wide, 4' deep and 1:1 sloped sides
Principle spillway
a) riser crest 1' below emergency spillway if present
b) riser crest stays within weir flow control during the 10yr storm
c) trash racks over all inlets and controls to prevent clogging
d) trash rack over riser crest is not flat (no DI -7's)
e) riser size and materials labeled
f) barrel size, strength, material, inverts and slope labeled
g) all orifices, weirs or other control devices labeled with dimensions and inverts
h) control orifices not more than 25% of riser perimeter at any point (does not
affect riser structural integrity, 25% is a target)
i) riser base size and dimensions labeled
j) access to riser is provided (riser should be in dam, not free-standing)
Emergency spillway
a) dimensioned and labeled
b) invert labeled
c) dimensions in control section
d) dimensions in channel section provided if different than control section
e) linings labeled and shown where applicable
f) spillway over native soils, and/or sufficient armoring provided
Sediment forebays
a) provided for all retention basins, constructed wetlands, and basin biofilters at
all inlets
b) sized to 0.25" of runoff per impervious acre (can be included in WQV)
c) direct vehicle access provided
Biofilters
a) minimum floor dimensions labeled
b) does not receive any stream base flows
c) areas of sheet flow into facilities are protected from erosion by appropriate
scour
d) protection stone or energy dissipation measure
e) plants are shown and labeled with height or caliper
f) 3 plant species are specified (3 trees if present, 3 shrubs) with sizes
g) biofilter floor is 2.5% of impervious cover for type I, or 4% of impervious
cover for type I1
h) 2.5' depth of sand/soil media
i) 1.5' stone drain in geotech fabric under media, with 6" perforated PVC pipe to
daylight
j) 0.5'-1.0' ponding depth provided in facility
k) overflow provided
1) biofilter area is flat
m) cleanouts are provided at the end of the underdrain pipe, and every 50'
47. Please remove the fire hydrant from within SWM facility #1.
Rev]: Please remove the.fire hydrant outside ofSWMfrrcility #4.
Additional Comments:
a) Please remove all water lines, gas lines, sanitary sewer lines, data conduits, electric
lines, stormwater overflow piping, etc. from the biofilter areas.
compromise the health of the tree.
Rev]: Tree protection must be shown at the drip line of trees per the VESCH to ensure the
protection of the trees. No construction or grading should occur within the limits of the tree
protection.
55. It appears the drive aisle down to the soil stockpile is not protected with any ESC measures.
Please address. [VESCH]
Rev]: Silt fence on the downhill side of the haul road is adequate. Provide diversions off the
uphill side of the haul road to divert runoff to sediment trap #2 and to keep runoff from
spilling onto the haul road
56. ESC measures appear to be in the way of site grading between phases 1 and 2.
Revl: comments not addressed. Please remove ESC measures in the way ofgrading and
replace with adequate perimeter controls.
57. Construction traffic shall only enter and exit the limits of disturbance through the approved
construction entrance. Please show a barricade in the locations where construction traffic may
be likely to leave the site without using the approved construction entrance. [VESCH]
Rev]: comments addressed.
58. Existing structure 1 I needs some form of protection. It appears that for both structures in this
vicinity, a culvert inlet sediment trap is the most reasonable measure to be used. [VESCH]
Rev]: comments addressed.
59. The northern property line is not adequately protected. Please address. [VESCH]
Rev]: comments addressed.
60. The ESC protection at the northern site entrance will need to be amended. The silt fence
through pavement in this area will be an inadequate ESC measure. [VESCH]
Rev]: comments addressed.
Additional Comments:
a) Portions of disturbance are not shown on the ESC plans (as the limits of disturbance
run off the page. All limits of disturbance must be clearly shown on all phases of the
ESC plans.
b) If existing swales are to be used to diversions, please provide calculations to show
that the swale will be adequate.
c) Temporary slope drains should be sized according to drainage area per the VESCH.
d) An ESC bond will be computed by the County once the plans have been approved.
b) The underground infiltration system should be designed according to an Infiltration
Trench: MOB of the VSMH. Please provide adequate depth and surface area
calculations. Pretreatment facilities are recommended at each inlet to prevent
clogging of the facility. The VSMH suggests that the facility is wrapped in filter
fabric, and that the insides of the detention pipes are also wrapped in fabric.
c) The underground facility does not appear to have enough storage. The maximum
elevation for the 2 and 10 year storms are above the top of the facility.
rte, d) It does not appear that an overflow structure has been provided for SWM #2.
e) The outlet of the SWM detention facility will always hold water because of the 2
riser structures in series. The 15" pipe will always remain in pressure flow. Please
combine the riser structures to one structure, or increase the 15" pipe to a 36" pipe
and provide a 3" drain down orifice on the second riser to keep standing water out
of structures.
f) It appears that the outlet structures for the detention facility are 15" risers
connecting to 15" pipes. How will this configuration work?
g) It appears that the detention facility may need to be lowered. It appears to be partly
located in fill. Infiltration facilities cannot be placed in fill. Also, it appears that there
in some areas, there is no space between the top of the gravel for the facility and the
base gravel for the concrete pavement. Lastly, there is a retaining wall within 5 feet
from the facility, with a bottom of wall elevation below the top elevation for the
facility. If the wall configuration is to remain, the wall should be designed with the
facility in mind.
h) Please label the elevations of the detention facility on sheet SWM -8.
i) A SWM bond will be computed by the County once the plans have been approved.
D. Erosion and sediment control comments:
49. Please include a detailed construction sequence in the erosion and sediment control narrative.
[VESCH]
Rev]: comments addressed.
50. The underground detention structure can not come online until the site has been deemed
stabilized by the county erosion and sediment control inspector. Please include this note on
the plan and demonstrate how the facility is to be constructed without being clogged. [DM]
Rev]: The construction sequence refers to plugging inlets and providing diversions. Please
show how this will work on the plans, and address how to ensure drainage will make it to
downstream traps or basins. Another possible solution may be to provide temporary slope
drains through the facilityfrom each inlet into the facility to keep sediment from entering
the facility, and to install the weir outlet structures after final stabilization has occurred and
the temporary slope drains are removed
51. The drainage area to sediment trap 2 is greater than 3 acres. A sediment basin is needed at this
location. [VESCH]
Rev]: comments not addressed. During the second phase of ESC, the drainage area to
sediment trap #2 will exceed 3 acres, as the drainage system will be conveyed to the trap.
Please size the trap for the entire southern drainage area, and provide adequate perimeter
protection with diversion dikes and temporary slopes drains to convey all drainage to a
basin. Realistically, this is what will happen in the field as sediment trap #4 is located in the
way of grading/construction. There appears to be plenty of space to provide perimeter
protection for the site draining to an adequate sediment basin at the lowest portion of the
site. This will allow the contractor to install ESC measures at the beginning of construction
and then he can focus on grading and construction of buildings and improvements.
52. Please show tree protection fencing on the plan per standard 3.08 in the VESCH or remove
from plan if not needed for other agency requirements. For example, the fencing must be
placed 5ft outside of the dripline of the tree. Also, it appears that in some locations, drainage
structures, silt fence placement, and grading will interfere with tree protection fencing and may
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Project: SDP -2006-00131, City of Charlottesville CTS Operations Center
WPO -2007-00091, City of Charlottesville CTS Operations Center
Plan preparer: Steve Davis, VMDO [email davisui?vmdo.com]
Owner or rep.: Scott Hendrix, Charlottesville [email: hendrix(�-i)charlottesville.org]
Date received: 24 October 2007 (plan rev. date 22 October 2007)
20 Mar 2008 (Revl)
Date of Comment: 12 December 2007
28 Apr 2008 (Revl)
Engineer: Phil Custer
Jonathan Sharp (Revl) [phone: 566-2578]
Engineering cannot recommend approval to the final major amendment for the City of Charlottesville CTS
Operations Center until the following comments have been addressed.
A. General review comments:
3. A temporary construction easement is required on TMP 77E 1-I D for the grading necessary to
construct the improvements on Avon Street Extended.
Rev]: comments not addressed/ At a ntinimunt, temporary construction easements can be
handled by a letter of intent by the owner of the parcel. I_f a formal easement is pursed, it
must be recorded prior to site plan approval.
5. Site plan approval cannot be granted until all of VDOT's concerns and comments have been
addressed. VDOT comments will be forwarded once we receive them.
Rev]: VDOT approval is required. A ropy of the plaits has been submitted to VDOT for
review.
6. For all review sections below, additional comments may be forthcoming on the next submittal.
Revl: See additional comments throughout the comment response letter.
B. Site Plan comments:
latest FEMA map. Please correct. [DM]
Rev]: comments addressed.
9. Not all critical slopes are hatched on the existing conditions sheet. Please show all slopes that
are greater than 25%. [32.5.6d]
Rev]: comments addressed.
10. The travelway in the parking lot must have a width of 24ft if parking spaces of less than l Oft
width are provided. [4.12.16c.1 ]
Revl: comments addressed.
11. Please provide more labels on the site plan indicating the types of curbing used. [DM]
Rev]: comments addressed.
12. In locations where curbing is proposed, please show two lines to demonstrate its width.
Sidewalks widths do not include the width of the curb. The applicant may have to adjust the
dimensioning in some areas if bumper blocks are to be avoided. [DM]
Rev]: The following in regards to parking areas must be revised:
a. In the parking area adjacent to the CTS operations building, the space directly
opposite the last fuel efficient vehicle space is only 14.4 7feet in length because part of
the space extends into the adjacent travelway (travelway measuring 22.73 ft in width).
Please reconfigure this part of the parking area so that spaces are a minimum of 16
feet in length.
b. Curbing is required for the parking spaces directly adjacent to the CTS maintenance
building. The width required for the curbing cannot be included in the 6 feet width
needed for the sidewalk.
c. Parking spaces directly adjacent to the CTS maintenance building must be 18 feet in
length.
d. The travelway adjacent to the CTS maintenance building is labeled as 26 feet in width
and the adjacent parking spaces opposite the building are labeled 16 feet in length,
when they should be labeled 24 feet and 18 feet, respectively. Please correct this.
13. The width of all parallel parking spaces must be 9ft. [4.12.16c.2]
Rev]: The travelway adjacent to the parallel parking should be 2 way in circulation and a
minimum of 20 feet wide.
14. Please show sight distance triangles onto VDOT ROW. [DM]
Rev1: comments addressed.
15. The minimum length of a loading space is 25ft. [4.12.18a]
Rev]: comments addressed.
16. The maximum grade for parking spaces, loading spaces, and access aisles abutting parking or
loading spaces shall not exceed five percent in any direction. [4.12.15c]
Rev]: The employee parking area adjacent to the CTS maintenance building between
elevations 435 and 441 is at a slope of 5.2%. Please revise to a maximum of 5% in slope.
17. There appears to be proposed slopes steeper than 2:1 on site. Please correct. [DM]
Revl: comments addressed.
18. Please provide an adequate landing all new entrances on the site. "As a guideline, the
approach grade should not exceed four percent for a distance of not less than forty feet
measured from the edge of the street being intersected." Please also include the VDOT
entrance designation on the grading sheet. [4.12.17b]
Rev]: The entrance to Avon Street adjacent to building D is shown at 5.4% in slope. Please
revise to a maximum of 4% slope for a distance of 40feet.
19. On sheets, S-1 and S-2 Type C pavement in the VDOT ROW was labeled as "Turf block".
Rev]: comments addressed.
20. Parallel parking spaces will not be permitted on Avon Street Extended.
Rev]: comments addressed.
21. There seems to be no overland flow relief if strictures 8-2 and 8-1 become clogged. Please
correct. [DM]
Revl: comments addressed.
S r de,�n► a � �S`� � `'�I- .fie ��� �- � �- ��"��
22. Site runoff must noTdrain into streets. Please correct grading ani drainage structures around
the southern entrance to fix this problem. [DM]
Rev]: cominews addressed.
23. All slopes steeper than 3:1 must have low maintenance groundcover specified. [DM]
Rev]: Low maintenance ground cover cannot be any type of grass.
Additional Comments:
a) I cannot find drainage area maps that correspond to the inlets. There should be
drainage area maps separate from the SWM drainage area maps, showing the
drainage going to each inlet. The SWM drainage area maps are confusing. Some of
the drainage areas do not correspond the actual areas draining to inlet. The
drainage areas shown for drainage structures along Avon Street do not include
ROW drainage, and do not match the drainage calculations. Several drainage areas
along Avon Street are missing. Please provide separate drainage area maps for the
drainage plan, with drainage areas corresponding to each inlet. The destination
structure of the drainage areas should be labeled for each drainage area. Also,
showing drainage pipes and structures on the drainage area map is helpful.
b) There appears to be an existing structure with endwall very close to line S-5 to S-13.
The plans do not indicate if this structure will be removed. Please clarify.
c) Portions of proposed improvements are missing on the grading plans (5-3,4) near
the northern entrance. Please include all proposed improvements on the grading
plans.
d) The drainage concept for the proposed cistern system is confusing. It appears that
roof runoff will drain to a large cistern in the CTS maintenance building. Will the
system be able to collect the first 1 inch of runoff for water quality volume
requirements? Please show that this volume will make it into the cistern, and will not
spill over the roof or gutters. Only this volume needs to be conveyed to the cistern
for water quality purposes Overflows can be provided at each building for larger
storm events so the large storm events do not pass through the cistern system. If
larger storms are not conveyed through the cistern (such as the 2 and 10 year
storm), identify which drainage structures convey the runoff and size the
structures/facilities appropriately to handle the additional runoff.
e) Please provide pipe profiles and calculations for the bus canopy drainage system.
f) There is a concern with the outfall of the proposed SWM facility #5. The outfall
appears to flow through a waste area, and there is a concern with sedimentation and
erosion in this area. Please provide a plan which will ensure the runoff from outfall
of the facility will not flow through the waste area.
V
g) Please analyze the existing drainage systems that the site ties into (structures 6-7, S-
13, and the DI below 4-8) to ensure that adequate downstream pipes/channels are
provided all the way to Moore's Creek. [MS -19]
C. Stormwater Management review comments:
31. Engineering review will consider the roofdrain collection and resupply systems private and not
subject to the normal requirements of our design manual. However, the downstream drainage
system should be designed assuming that the cistern overflows for all design storm and
provides no detention at all.
Rev]: Additional information is needed for the cistern system. See comments about
drainage in the additional comment d) under the site plan comments and comment 32
below. It appears that the cistern is still being used for detention.
32. Engineering review will give quality credit for the use of the cistern if it is sized to capture the
water quality volume for the all the buildings. Please provide this calculation and a simple
detail of the cistern showing its dimensions.
Rev]: Please provide a detail of the cistern in the SWM plans. Our water quality
requirements are based on volume. The first I inch of runoff must be able to be collected
within the cistern. Please show that the first I inch of runoff will make it into the cistern
(not overflow over the gutter system on the roofs of buildings) and that the cistern can hold
the volume of the first I inch of runoff in addition to an average storage volume of water in
the tank for between storms. Will the water in the tank be used up very quickly? Please
calculate an average volume of water that will be stored in the cistern based on water usage
so that if a storm event occurs the entire 1 inch of runoff will be treated and will not
overflow from the cistern.
33. Drainage area lines appear to be incorrect in some places. Please correct. Drainage area lines
should not stop at property lines in analysis. To perform an accurate analysis, the applicant
may need to use a different scale to provide a fuller view of the development and the
surrounding points of analysis for the drainage area maps.
Rev]: comments not addressed Drainage area maps for stormwater detention should
include all areas draining to analysis points, facilities, or structures. Please show the area
draining to each facility. -1 pkft1 a r• S , vdvk 5 ,Ao a,,CR x S
34. It appears that the removal rate provided in SWM facilities #2 and #4 are inadequate for the
drainage area. Please correct. [VSMH, DM]
Rev]: Water quality drainage areas should not include offsite drainage areas when
calculating removal rates. SWMfacility #2 includes offsite area. When done correctly, the
removal rates for facility #2 becomes 65%. Also, in the water quality compliance table, the
removal rate for SWM #4 is listed as 100%, when it should be listed as 65% (removal rate
of an infiltration trench).
35. It appears that no stormwater treatment will occur in the underground facility. Please provide
treatment in this area. If infiltration credit is sought, the applicant must supply soil tests
verifying that the soil is adequate to use an infiltration measure. Generally, the soils found in
this region do not allow for infiltration to be used with any degree of confidence. [DM]
Rev]: The underground facility should be designed as an Infiltration Trench (VSMH 3.10).
Our water quality requirements are based on volume. In order to achieve a 65% removal
rate, the facility must be sized to infiltrate the first I inch of runoff. The volume used for
infiltration should not be included in the storage volume for detention. For example, if 220
cu yd are needed for water quality volume and this volume is located at elevation 438, then
storage for detention routing should begin at elevation 438.
36. Detention calculations appear to be missing. Please route all detention structures to show that
all detention requirements are met. [DM]
Rev]: The detention calculations are very confusing. The narrative states that only the
underground facility will be utilized for detention, when it appears on the detention
compliance table all the facilities are being used for detention. The compliance table shows
that the 10 year storm is not met for the rational method. The rational method should be
used for drainage areas of the small size found on site. The detention compliance table is
very confusing. Areas not draining to the underground facility are being treated as if they
are being routed through the facility. Please show the total drainage draining to each
facility (as the facilities are in series and downstream facilities capture drainage from
upstream facilities). There is not enough information provided to verify whether or not
detention is met. Calculations should include all outlet structure information. Typically the
downstream most facilities are designed and sized to handle stormwater detention, and
upstream facilities serve only as water qualityfacilities. There are too many questions and
concerns to discuss in a comment letter. Please contact Engineering to discuss how
stormwater detention is handled and consult the County Design Manual. 'I-WOCs A'k3 5 —Z-
37. It is unclear how any detention is provided on site. Please provide greater details on the outlet
control structures for all detention facilities. See above comment.
Rev]: Stormwaterfacility outlet structure information should be located on the SWMplan
sheet included with the cross sections for each facility. See comment #44.
38. Sediment forebays are required on all water quality facilities that receive concentrated flow.
Please design each forebay to the standard in the Virginia Stormwater Management
Handbook. [VSMH]
Rev]: Forebays are needed for SWM facilities #1 and #2.
39. It appears that development of this site will demolish the existing stormwater management
facility and replace it with a new one. If this is the case, the pre -development analysis should
assume an undeveloped site because the site is currently detaining water to meet the initial
pre -development rate.
Rev]: comments addressed.
40. Please include the planting plan for each biofilter in the stormwater section of the plan set.
Each biofilter detail should have its own planting schedule. [DM]
Revl: comments addressed.
41. Please provide sizing calculation for each biofilter. [DM]
Rev1: Biofilter sizing calculations are based on surface area, not volume. Biofilter floors
should be sized for 2.5% of the impervious area draining to the facilityfor a 50% removal
rate requirement, and 4% of the impervious area draining to the facilityfor a 65% removal
rate requirement
42. Please label minimum bed dimensions in each biofilter. [DM]
Revl: comments addressed.
43. Each biofilter shall specify 3 species of tree and 3 species of shrub. [VSMH, DM]
Rev]: comments addressed.
44. Please provide a typical section for each biofilter. [DM]
Rev]: Cross-sections are needed for each biofilter including the following information and
meeting the following criteria (directly from Design Manual):
Embankments (between 3 and 25 ft in height)
a) top width 811 min., 10' for heights 15' to 20', 12' for dams over 20', heights
measured from the outside toe
b) upstream face slope 2:1 or flatter, labeled
c) downstream slope 3:1 or flatter, labeled
d) 10yr and 100yr high water elevations labeled with 1 ft freeboard for 100yr
storm with emergency spillway or 2 ft freeboard without emergency spillway
e) an impervious core
f) a cutoff trench of minimum 4' wide, 4' deep and 1:1 sloped sides
Principle spillway
a) riser crest 1' below emergency spillway if present
b) riser crest stays within weir flow control during the 10yr storm
c) trash racks over all inlets and controls to prevent clogging
d) trash rack over riser crest is not flat (no DI -7's)
e) riser size and materials labeled N,
I) barrel size, strength, material, inverts and slope labeled
g) all orifices, weirs or other control devices labeled with dimensions and inverts
h) control orifices not more than 25% of riser perimeter at any point (does not
affect riser structural integrity, 25% is a target)
i) riser base size and dimensions labeled
j) access to riser is provided (riser should be in dam, not free-standing)
Emergency spillway
a) dimensioned and labeled
b) invert labeled
c) dimensions in control section
d) dimensions in channel section provided if different than control section
e) linings labeled and shown where applicable
f) spillway over native soils, and/or sufficient armoring provided
Sediment forebays
a) provided for all retention basins, constructed wetlands, and basin biofllters at
all inlets
b) sized to 0.25" of runoff per impervious acre (can be included in WQV)
c) direct vehicle access provided
Biofilters
a) minimum floor dimensions labeled
b) does not receive any stream base flows
c) areas of sheet flow into facilities are protected from erosion by appropriate
scour
d) protection stone or energy dissipation measure
e) plants are shown and labeled with height or caliper
f) 3 plant species are specified (3 trees if present, 3 shrubs) with sizes
g) biofilter floor is 2.5% of impervious cover for type I, or 4% of impervious
cover for type 11
h) 2.5' depth of sand/soil media
i) 1.5' stone drain in geotech fabric under media, with 6" perforated PVC pipe to
daylight
j) 0.5'-1.0' ponding depth provided in facility
k) overflow provided
1) biofilter area is flat
m) cleanouts are provided at the end of the underdrain pipe, and every 50'
47. Please remove the fire hydrant from within SWM facility #1.
Rev]: Please remove the fire hydrant outside of SWM facility #4.
Additional Comments:
a) Please remove all water lines, gas lines, sanitary sewer lines, data conduits, electric
lines, stormwater overflow piping, etc. from the biofilter areas.
b) The underground infiltration system should be designed according to an Infiltration
Trench: 3.10B of the VSMH. Please provide adequate depth and surface area
calculations. Pretreatment facilities are recommended at each inlet to prevent
clogging of the facility. The VSMH suggests that the facility is wrapped in filter
fabric, and that the insides of the detention pipes are also wrapped in fabric.
c) The underground facility does not appear to have enough storage. The maximum
elevation for t`fie 2 and 10 year storms are above the top of the facility.
d) It does not appear that an overflow structure has been provided for SWM #2.
e) The outlet of the SWM detention facility will always hold water because of the 2
riser structures in series. The 15" pipe will always remain in pressure flow. Please
combine the riser structures to one structure, or increase the 15" pipe to a 36" pipe
and provide a 3" drain down orifice on the second riser to keep standing water out
of structures.
f) It appears that the outlet structures for the detention facility are 15" risers
connecting to 15" pipes. How will this configuration work?
g) It appears that the detention facility may need to be lowered. It appears to be partly
located in fill. Infiltration facilities cannot be placed in fill. Also, it appears that there
in some areas, there is no space between the top of the gravel for the facility and the
base gravel for the concrete pavement. Lastly, there is a retaining wall within 5 feet
from the facility, with a bottom of wall elevation below the top elevation for the
facility. If the wall configuration is to remain, the wall should be designed with the
facility in mind.
h) Please label the elevations of the detention facility on sheet SWM -8.
i) A SWM bond will be computed by the County once the plans have been approved.
D. Erosion and sediment control comments:
49. Please include a detailed construction sequence in the erosion and sediment control narrative.
[VESCH]
Rev]: comments addressed.
50. The underground detention structure can not come online until the site has been deemed
stabilized by the county erosion and sediment control inspector. Please include this note on
the plan and demonstrate how the facility is to be constructed without being clogged. [DM]
Rev]: The construction sequence refers to plugging inlets and providing diversions. Please
show how this will work on the plans, and address Trow to ensure drainage will make it to
downstream traps or basins. Another possible solution may be to provide temporary slope
drains through the facility from each inlet into the facility to keep sediment from entering
the facility, and to install the weir outlet structures after final stabilization has occurred and
the temporary slope drains are removed.
51. The drainage area to sediment trap 2 is greater than 3 acres. A sediment basin is needed at this
location. [VESCH]
Rev]: comments not addressed During the second phase of ESC, the drainage area to
sediment trap #2 will exceed 3 acres, as the drainage system will be conveyed to the trap.
Please size the trap for the entire southern drainage area, and provide adequate perimeter
protection with diversion dikes and temporary slopes drains to convey all drainage to a
basin. Realistically, this is what will happen in the field as sediment trap #4 is located in the
way of grading/construction. There appears to be plenty of space to provide perimeter
protection for the site draining to an adequate sediment basin at tlhe lowest portion of the
site. This will allow the contractor to install ESC measures at the beginning of construction
and then he can focus on grading and construction of buildings and improvements.
52. Please show tree protection fencing on the plan per standard 3.08 in the VESCH or remove
from plan if not needed for other agency requirements. For example, the fencing must be
placed 5ft outside of the dripline of the tree. Also, it appears that in some locations, drainage
structures, silt fence placement, and grading will interfere with tree protection fencing and may
compromise the health of the tree.
Rev]: Tree protection must be shown at the drip line of trees per the VESCH to ensure the
protection of the trees. No construction or grading should occur within the limits of the tree
protection.
55. It appears the drive aisle down to the soil stockpile is not protected with any ESC measures.
Please address. [VESCH]
Rev]: Silt fence on the downhill side of the haul road is adequate. Provide diversions all the
uphill side of the haul road to divert runoff to sediment trap #2 and to keep runoff from
spilling onto the haul road
56. ESC measures appear to be in the way of site grading between phases 1 and 2.
Rev]: comments not addressed Please remove ESC measures in the way of grading and
replace with adequate perimeter controls.
57. Construction traffic shall only enter and exit the limits of disturbance through the approved
construction entrance. Please show a barricade in the locations where construction traffic may
be likely to leave the site without using the approved construction entrance. [VESCH]
Reel: comments addressed.
58. Existing structure 11 needs some form of protection. It appears that for both structures in this
vicinity, a culvert inlet sediment trap is the most reasonable measure to be used. [VESCH]
Revl: comments addressed.
59. The northern property line is not adequately protected. Please address. [VESCH]
Rev]: comments addressed.
60. The ESC protection at the northern site entrance will need to be amended. The silt fence
through pavement in this area will be an inadequate ESC measure. [VESCH]
Rev]: comments addressed.
Additional Comments:
a) Portions of disturbance are not shown on the ESC plans (as the limits of disturbance
run off the page. All limits of disturbance must be clearly shown on all phases of the
ESC plans.
b) If existing swales are to be used to diversions, please provide calculations to show
that the swale will be adequate.
c) Temporary slope drains should be sized according to drainage area per the VESCH.
d) An ESC bond will be computed by the County once the plans have been approved.
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Project: SDP -2006-00131, City of Charlottesville CTS Operations Center
WPO -2007-00091, City of Charlottesville CTS Operations Center
Plan preparer: Steve Davis, VMDO [email: davis(a vmdo.com]
Owner or rep.: Scott Hendrix, Charlottesville [email: hendrix(ii)charlottesville.org]
Date received: 24 October 2007 (plan rev. date 22 October 2007)
20 Mar 2008 (Rev] )
17 June 2008 (Rev2)
Date of Comment: 12 December 2007
28 Apr 2008 (Rev] )
14 July 2008 (Rev2)
Engineer: Phil Custer
Jonathan Sharp (Rev1,2) [phone: 566-2578]
Please address the following comments (see General review comment #3 and additional SWM comment a)
and submit the following complete plans for our files:
Four (4) copies of the ESC plans
Three (3) copies of the SWM plans
No additional calculation packages are needed.
The plans must be approved by all departments and divisions and the ESC and SWM bonds must be
posted before construction can begin.
A. General review comments:
149
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A temporary construction easement is required on TMP 77131-1 D for the grading necessary to
construct the improvements on Avon Street Extended.
Revl: comments not addressed. At a minimum, teniporary construction easements can be
handled by a letter of intent by the owner of the parcel. If a formal easement is pursed, it must
be recorded prior to site plan approval.
Rev2: The pending plat must be recorded prior to site plan approvaL
B. Site Plan comments:
C. Stormwater Management review comments:
Additional Comments:
a) Please remove all water lines, gas lines, sanitary sewer lines, data conduits, electric lines,
stormwater overflow piping, etc. from the biofilter areas.
Rev]: A sanitary sewer litre is shown going through SWM#6. I could trot verify
checking this contntent fully because the Extended Areas Utility Plan was trot included
with this submittal. Remove all utilities front biofilter floor areas.
b)
C)
d)
e)
fl
g)
h)
i) A SWM bond will be computed by the County once the plans have been approved.
Rev2: The SWM bond is set at $419,000.
D. Erosion and sediment control comments:
a)
b)
C)
d) An ESC bond will be computed by the County once the plans have been approved.
Rev2: The ESC bond is set at $68,000.
Albemarle County
Service Auth4rity
Serving ♦ Com ?rving
March 10, 2009
Mr. Justin Walton
VMDO Architects
200 East Market Street
Charlottesville, Virginia 22902
Re: City of Charlottesville CTS Operations Center
Dear Mr. Walton:
The plan, entitled "City of Charlottesville CTS Operations Center"
dated March 17, 2008, last revised January 12, 2009, is hereby approved for
construction. One set of the approved plan is enclosed for your records. Any previously
approved plans are voided with this approval. This approval is for basic compliance with
the General Water & Sewer Construction Specifications of the Albemarle County Service
Authority (ACSA) and does not relieve the contractor from responsibility for his work as it
relates to the plan and specifications.
The ACSA requires that a copy of the approved construction plan be on the job
site. The contractor is responsible for marking up a copy of the approved construction
plan showing as -built information and provide this data to your client at the completion of
utility installation. The final as -built plan shall be submitted in a format of one paper copy
and one mylar copy.
A preconstruction conference shall be scheduled with the project manager to
ensure coordination and answer any questions. This will be a short meeting to review the
project, materials, test methods and schedule, in order to expedite construction. Please
have the proper party call me at 977-4511 to schedule the meeting.
This approval is valid for a period of 18 months from this date. If construction is
not in progress at the end of this time period, the approval shall be void.
(The pressure for water may exceed 80 psi at some meter locations).
168 Spotnap Road e Charlottesville, VA 22911 • Tel (434) 977-4511 • Fax (434) 979-0698
www.serviceauthority.org
If you have any questions, or if we can be of assistance, please give us a call at
(434) 977-4511.
Sincerely,
Gary M. Whelan
Civil Engineer
GMW:dmg
cc: Judith Mueller
State Health Department
urrent Development, Bill Fritz
Bldg Codes & Zoning Services
Soil Erosion Inspector
050601 WaltonCTSUM1609