HomeMy WebLinkAboutSDP200800081 Review Comments 2008-07-21tiOF AL@Er7
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: J.W. Townsend Landscaping Improvements — Minor Amendment
SDP200800081 ]
Plan preparer: Jim Taggart, TCS Engineering [fax 361 -12161
Owner or rep.: J.W. Townsend [email jay @townsendlandscape.com]
Plan received date: 27 May 2008
Date of comments: 21 Jul 2008
Reviewer: Amy Pflaum, Current Development Review Engineer
A. Minor Site Plan Amendment
1. Easements or letters of intent are required for off -site work. It appears that temporary grading and
construction easements will be necessary from TMP's 32 -6A and 32 -22B1. Please submit
easement documents for all new easements or demonstrate that these easements are not necessary.
2. All slopes steeper than 3:1 will require non - grassed low maintenance ground cover, please specify
with a note on the plan. [DM]
3. In the Albemarle County Development Area, curbing is required on all parking areas and
travelways with VDOT designations (CG -2, CG -6).
4. Although labeled as 8.25% on the plan, the portion of the proposed travelway uphill of the two
new parking areas is graded at 20 %. Travelways should not exceed a 10% grade.
5. A guardrail with VDOT designations (GR -2, GR -2a, etc.) is required next to parking or travelways
adjacent to retaining walls or drop -offs of greater than 4 feet, with start and end sections labeled.
18-32.7.21
6. An Erosion & Sediment Control Plan and Stormwater Management Plan are required. Please
submit along with a Water Protection Ordinance application. Comments #7 -16 will need to be
addressed with the WPO.
Please show the limits of the drainage area to the proposed stormwater management pond and sub-
areas to the culverts.
8. Please provide culvert computations for the two proposed culverts under the travelway.
9. Please include the acreage of disturbance in the project description of the narrative.
10. Please provide a cross section detail of the proposed pond.
11. The pond is sized as a detention facility, but no outlet structure is shown. Please provide details
and sizing calculations for the outlet structure.
12. Please address the stormwater management of the concentrated run -off from the proposed pond.
Identify the adequate channel from this site. It appears a drainage easement may be needed from
TMP 32 -22B 1.
13. A stormwater management easement is required around the proposed pond and any associated
Albemarle County Community Development
Engineering Review Comments
Page 2 of 2
structures.
14. Please provide for vehicle access to the proposed pond. Access must be graded to 10' width and
less than 20% grade, gravel surface or better is required for grades over 10 %. Please provide a
minimum 10' wide permanent easement over the access.
15. A SWM bond amount will be computed by the County once the WPO plans have been approved.
A completed copy of the standard stormwater maintenance agreement and fee for recordation for
any stormwater management facilities will be required. [ 17 -304E]
16. An E &S bond amount will be computed by the County once the WPO plans have been approved.
Application #: SDP200800081 ;short Review Commits
Project Name: IJ.W. Townsend Landscaping Improvements- Minor IminorAmendment
Date Completed: 07/22/2008
Reviewer: Amy Pflaum Engineer Z &CD
Review Status: Requested Changes
Reviews Comments: I Faxed to TCS Engineering and emailed to JWTownsend, 7/22/08
Date Completed:
Reviewer:
Review Status:
Reviews Comments:
06/04/2008
Bill Fritz Planner Z &CD
Administrative Approval
approved subject to approval of the stormwater calculations
Page: 1.00 County of Albemarle Printed On: Wednesday, September 23, 2009
44 JP
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: J.W. Townsend Landscaping Improvements — Minor Amendment
SDP20080008I ]
Plan preparer: Jim Taggart, TCS Engineering [fax 361 -1216]
Owner or rep.: J.W. Townsend [email jay (u)townsendlandscape.com]
Plan received date: 4 June 2008
Rev, 1: 25 August 2008
Date of comments: 22 July 2008
Rev, 1: 25 Sept. 2008
Reviewer: Amy Pflaum, Current Development Review Engineer
Rev.l : John Diez, Current Development Engineering Technician
Minor Site Plan Amendment Comments
1. Easements or letters of intent are required for off -site work. It appears that temporary grading and
construction easements will be necessary from TMP's 32 -6A and 32 -22131. Please submit
easement documents for all new easements or demonstrate that these easements are not necessary.
Rev. 1) Continent has not been addressed
3. In the Albemarle County Development Area, curbing is required on all parking areas and
travelways with VDOT designations (CG -2, CG -6).
Rev. 1) Comment has not been addressed. Ifyon do not wish to add curb, then please submit a
waiver request as per section 18.4.12.2.c.2.
4. Although labeled as 8.25% on the plan, the portion of the proposed travelway uphill of the two
new parking areas is graded at 20 %. Travelways should not exceed a 10% grade.
Rev. 1) Comment has not been addressed. There still seems to be grades that exceed 10% on
the travelway.
5. A guardrail with VDOT designations (GR -2, GR -2a, etc.) is required next to parking or travelways
adjacent to retaining walls or drop -offs of greater than 4 feet, with start and end sections labeled.
18- 32.7.2]
Rev. 1) Comment has not been addressed
7. Please remove all Erosion & Sediment Control features on the Site Plan.
A1bemCounty Community Development
Engineering Review Comments
Page 2 of 3
8. Location of the retaining wall is not clear. Please provide start and end elevations for the retaining
wall, as well as elevation marks throughout the wall.
9. Please provide retaining wall details referenced from the plans. A typical manufacturers drawing
for segmented block walls, or VDOT reference, is acceptable, with any applicable safety railings
or guardrail shown.
10. Small scale of plan makes it difficult to determine dimensions of parking and loading spaces.
Stormwater Management Plan Comments
11. Please -,iiow tlic° ii. €IJ.ts o.r tlac drainage area to tlae prg3 , A stc,rrnN titer n.wIlao pond and sub-
areas to the culverts.
Rev 1) ( "mmuent has been addressed
I' . Pleaase provicl_e culvert conalatatatiwos for the two proposed culverts un(lcr° the travclway
Rea'. ) Comment has been rarddre.:o ;ed
13. Plca prop idc :a cross scctioli det:lil of ti'ac, proposed Pond,
Rev. 1) Comment leas been addressed
14. The hood is sized as <a detention facility. but aria outlet struefr € €°c is shown, 1'lc &tse provi& de fails
and sizing calculations for the owlet. structure.
Rev. 1) C oararneut has been addressed
15. Please address the stormwater management of the concentrated run -off from the proposed pond.
Identify the adequate channel from this site. It appears a drainage easement may be needed from
TMP 32 -22131.
Rev. 1) Comment has not been addressed. Concentrated run -offfrom the proposed pond has
not been addressed. Concentrated run -off appears to be flowing to the neighboring property.
Please identify the adequate channel from this site. Also, please provide a drainage easement
from TMP 32 -22B1.
16. A stormwater management easement is required around the proposed swale and pond and any
associated structures.
Rev. 1) Comment has not been addressed. The easement must be extended to the property line
by Rte. 29
17. 1 provide for velaicic : to flag propr 'wd pond. Access must he graded t 10' width an
Icss than ?( }c; }radc., 'ara-el surfhec or beller is rc(lu.ired .6or grades over 1 W'o.. Please pr°ovi €ie a
minirnuin 10' Wide permanent easement o %vr the acecss. _
Rev. 1) C'rar,rsrr ent has been addressed
18. A Stormwater Management bond amount will be comput by the County once the WPO plans
have been approved. A completed copy of the standard st water maintenance agreement and fee
for recordation for any stormwater management facilities '1 be required. [17 - 304E]
19. Please submit a completed copy of the standard Stormwater Maintenance Agreement and fee for
recordation for the proposed stormwater management facilities.
20. Please provide all existing easements with deed book references, locations and dimensions [18-
32.6.6, 14 -302]
AlbemaoCounty Community Development
Engineering Review Comments
Page 3 of 3
21. Please provide a detail of the proposed grassed swale per the VSMH (blue book) 3.13
22. Please specify all dimensions on the outlet protection detail.
23. Please include a detention summary table with pre - development and post - development ratecalculations.
24. Please provide a float calculation for the pond riser structure V
25. If the pond is to provide extended detention, please design per the VS4*lue book) 3.07.
26. Please simplify post - development calculations so that there is one drainage area to the pond.
27. Please specify water quality volume (WQV) method and counts.
28. Please provide a plan view of the pond at a larger scale so that we may review the grading. ScaleshouldbeI" = 20' — 30'.
Erosion & Sediment Control Plan Comments
29. An Erosion & Sediment Control bond amount will be computed by the County once the WPO
plans have been approved.
et'. Please i3,,°.l ldca G dare ale ofdisturhanc: ° ill ttae prk)'ject descriptioia ol'the n arraP.u"e,
Rev= 1 ) (car r rc> t has been addrcs.
31. Is the proposed pond to serve as a sediment basin during construction? If so, please provide sizingcalculationsanddetailspertheVESCH3.14
t ;, >t,.. t i} I `cityz i.c °tip IF ' i:) ; , .'t }i)K`•.tii)I' .:1 t''.f?ia (i( t) i l J,W, I circ a`, rci`.i:'' n;x . -na .1PD
D
ble heC
WP= I'
hzo 05
l
1
l
0, m
n = 0,
075
J
o, 05
x,
37 51( P
v, =o.
o7s
v =(), C / ) 5 f -
j
complex channnel
input:
downstream channel xl.txt
Slope
Q V
0.080
P
Flow (given)
0.00 0.00
2.580
0.00
2
line x y n
3
0 0.000 3.400 0.075 (first n value not used)
4
1 10.000 2.440 0.075
5
2 22.000 2.300 0.050
6
3 22.250 2.000 0.050
7
4 23.250 2.000 0.050
5 23.500 2.300 0.050
6 35.500 2.400 0.075
7 45.500 3.500 0.075
Output:
Depth 0.384
Y)C 2.384)
channel bed segment output:
line Q V A P
1 0.00 0.00 0.00 0.00
2 0.31 1.02 0.30 7.21
3 0.14 2.37 0.06 0.39
4 1.71 4.44 0.38 1.00
5 0.14 2.37 0.06 0.39
6 0.29 0.68 0.42 10.10
7 0.00 0.00 0.00 0.00
Thu jun 04 09:07:05 EDT 2009
Page 1
AL
9
L "' r
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project:
Plan preparer:
Owner or rep.:
Plan received date
Rev, 1:
Rev,2:
Date of comments
Rev, l :
Rev,2:
Reviewer:
Rev. l &2
J.W. Townsend Landscaping Improvements — Minor Amendment
SDP200800081 ]
Jim Taggart, TCS Engineering [fax 361 -1216]
J.W. Townsend [email jay@townsendlandscape.com]
4 June 2008
25 August 2008
11 March 2009
22 July 2008
09 October 2008
30 March. 2009
Amy Pflaum, Current Development Review Engineer
John Diez , Current Development Engineering Technician
Minor Site Plan Amendment Comments
1. Easements or letters of intent are required for off -site work. It appears that temporary grading and
construction easements will be necessary from TMP's 32 -6A and 32 -22131. Please submit
easement documents for all new easements or demonstrate that these easements are not necessary.
Rev. 1) Comment has not been addressed.
Rev. 2) Comment has not been addressed.
Albemarleounty Community Development
Engineering Review Comments
Page 2 of 5
A guardrail with VDOT designations (GR -2, GR -2a, etc.) is required next to parking or travelways
adjacent to retaining walls or drop -offs of greater than 4 feet, with start and end sections labeled.
18- 32.7.2]
Rev. 1) Comment has not been addressed.
Rev. 2) Comment has not been addressed. Bumper blocks are needed on the parking spaces
southeast of the relocated shed. Guardrails are required where there is a 2:1 slope. For
example, adjacent to the southwest corner of the lower parking lot and adjacent to the
travelway leading up to the lower parking lot. An alternative to guardrails is to provide 3:1
slopes adjacent to the parking or travelwajs.
Stormwater Management Plan Comments
Albemarleounty Community Development
Engineering Review Comments
Page 3 of 5
15. Please address the stormwater management of the concentrated run -off from the proposed pond.
Identify the adequate channel from this site. It appears a drainage easement may be needed from
TMP 32 -22B1.
Rev. l) Comment has not been addressed. Concentrated run -offfrom the proposed pond has
not been addressed. Concentrated run -off appears to be flowing to the neighboring property.
Please identify the adequate channel from this site. Also, please provide a drainage easement
from TMP 32 -22B1.
Rev. 2) Comment has not been addressed. Please provide an adequate channel analysis
meeting all requirements from the County's Design Manual.
18. A Stormwater Management bond amount will be computed by the County once the WPO plans
have been approved. A completed copy of the standard stormwater management maintenance
agreement and fee for recordation for any stormwater management facilities will be required. [17-304E]
Rev. 2) Comment has not been addressed.
19. Please submit a completed copy of the standard Stormwater Maintenance Agreement and fee for
recordation for the proposed stormwater management facilities.
Rev. 2) Comment has not been addressed.
21. Please provide a detail of the proposed grassed swale per the VSMH (blue book) 3.13
Rev. 2) Comment has not been addressed. Please remove the note on the plans if a swale is not
provided.
Albemarleounty Community Development
Engineering Review Comments
Page 4 of 5
25. If the pond is to provide extended detention, please design per the VSMH (blue book) 3.07.
Rev. 2) This plan does not provide water quality to state standards. As computed by the
applicant, the required removal rate for the project is 30 %. The Virginia Stormwater
Management Handbook identifies several BMPs that provide this removal rate. For example,Extended Detention Basins, Type I Retention Basins, and Water Quality Swales are all
accredited a 35% removal rate by the VSMH. It appears that the applicant has attempted to
design a retention basin for water quality treatment Unfortunately, the minimum drainage
area for retention basins (as specified in the VSMH and included in Albemarle County's
Design Manual) is IO acres. The use of a retention basin in this location is not appropriate.All of these items were discussed in the telephone conversation between Phil Custer and Mr.
Taggart.
It should be noted that no matter the BMP specified for this project, sediment forebays are
required. The removal rates attributed to most BMPS assume that an appropriately sizedsedimentforebayisprovided.
27. Please specify water quality volume (WQV) method and counts.
Rev 2) Please see comment #25.
28. Please provide a plan view of the pond at a larger scale so that we may review the grading. ScaleshouldbeI "= 20' — 30'.
Rev 2) Comment has been addressed However, the grading of the pond must be changed inordertoprovidewaterqualitytreatment
29. (Rev.2) Please provide an updated Routing Report after the basin is modified.
30. (Rev. 2) Please remove the note regarding future stormwater management review. When a future
site plan amendment is submitted, a stormwater management amendment will be required. Or, the
applicant will be required to prove adequacy of the constructed facility.
Erosion & Sediment Control Plan Comments
30. An Erosion & Sediment Control bond amount will be computed by the County once the WPOplanshavebeenapproved.
32. Is the proposed pond to serve as a sediment basin during construction? If so, please provide sizingcalculationsanddetailspertheVESCH3.14
Rev. 2) Comment has not been addressed. This facility must act as a Sediment Basin duringconstruction.
Albemarle ounty Community Development
Engineering Review Comments
Page 5 of 5
Page 1 of 3
Philip Custer
From:Philip Custer
Sent:Tuesday, April 07, 2009 3:37 PM
To:Jay Townsend'; JTAGG2 @aol.com
Cc:Amy Pflaum; John Paul Diez
Subject:RE: Townsend Water records
Attachments: TOWNS ENDwaterrecords2008.x1s; VAnorm.pdf
Jay,
The attached excel file is a modification to the original file sent to me by Jim. I have added a new sheet to the
document to help me summarize the rainfall per month that we get in the Albemarle /Charlottesville area. The
yearly data towards the left of the table was pulled from weatherunderground.com. The average monthly data
was taken from the NOAA document (also attached).
What isn't shown in the calculations is the comparison between Water Quality volume and consumption.
Basically, the rain that falls over all impervious surfaces must be treated (it's actually the first 0.5in of every
rainstorm but most of the annual rainfall comes in storms less than 0.5in.).
I'll run through the January calculation:
NOAA rainfall: 3.71 acres
Impervious area in watershed: 31 % of 5.27acres = 71,164 cubic feet (cf)
Water quality volume (assuming storms in January less than 0.5in.): 22,002
Max. January irrigation use: 2,286 cubic feet (cf)
Obviously, this is one of the worst case scenarios considering the time of year and we acknowledge that during
summer months the consumption is well above the water quality volume. However, we are looking for a year
round water quality solution. The county is more comfortable with the water quality method suggested in my
last email (extended detention) for this site. Below the volume needed for the extended detention portion of the
facility, you can excavate more soil for a wet pond for irrigation purposes, if desired.
Please feel free to contact me if you have any additional questions. Jim, if you want to discuss the design
adjustments before putting it to paper, please also do not hesitate to call.
Thanks,
Phil
From: Jay Townsend [mailto :jay @townsendlandscape.com]
Sent: Tuesday, April 07, 2009 11:15 AM
To: Philip Custer; 3TAGG2 @aol.com
Cc: Amy Pflaum; John Paul Diez
Subject: RE: Townsend Water records
Phil,
Thank you for your effort, note and comments.
Can you provide for me the noaa numbers and calculations to help me understand your thoughts. From a
practical stand point, the cistern concept seems to be a "win win" for everyone; the county water supply and our
business. I do not understand what could be detrimental about this approach; no more water goes downstream
than before, and what does go down, is "better controlled ".
I look forward to hearing from you.
9/21 /2009
Page 2 of 3
Thanks,
Jay
Jay Townsend
President
J.W. Townsend, Inc.
Landscape Contractor
PO Box 5551
Charlottesville, VA 22905
Phone: 434 - 973 -1154
Fax: 434 - 973 -1578
www.townsendiandsca
From: Philip Custer [mailto:pcuster @albemarle.org]
Sent: Tuesday, April 07, 2009 10:45 AM
To: JTAGG2 @aol.com; jay @townsendlandscape.com
Cc: Amy Pflaum; John Paul Diez
Subject: RE: Townsend Water records
Jim, Jay,
I have given the issue considerable thought the past few days and have spoken with Glenn and Amy. After
looking at the water usage information you gave me on Friday, the drainage area hydrology to the pond, and
the historical rainfall data for the area from noaa.gov, it appears that the numbers do not support the use of the
pond as a cistern for water quality use. You may however design the facility as an extended detention basin
and excavate extra soil below the invert elevation of the lowest orifice for on -site irrigation use. I was willing to
consider this an option at our meeting on Thursday because I had over - estimated the water consumption of the
site and under - estimated the rainfall we receive during the winter months.
A full downstream channel analysis will still be required. Please also update the routing computations after the
basin characteristics have been modified. A drainage easement on the downstream property will not be
required unless improvements must be made to upgrade the channel.
Please feel free to contact me with any questions you have for the project.
Thanks,
Phil
From: 3TAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Friday, April 03, 2009 7:56 AM
To: Philip Custer
Cc: jay @townsendlandscape.com
Subject: Townsend Water records
Phil,
Water records as discussed.
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
9/21/2009
Page 3 of 3
ph. 434.361.1215
Feeling the pinch at the grocery store? Make dinner for-$10 or less.
9/21 /2009
N
kctN
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: J.W. Townsend Landscaping Improvements — Minor Amendment
SDP200800081 ]
Plan preparer: Jim Taggart, TCS Engineering [fax 361 -1216]
Owner or rep.: J.W. Townsend [email jay a,townsendlandscape.com]
Plan received date: 4 June 2008
Rev, 1:
Rev,2:
Rev,3:
Date of comments:
Rev, 1:
Rev,2:
Rev,3:
Reviewer:
Rev. l & 2:
Rev. 3:
25 August 2008
11 March 2009
5 May 2009
22 July 2008
09 October 2008
30 March. 2009
27 May 2009
Amy Pflaum, Current Development Review Engineer
John Diez, Current Development Engineering Technician
Phil Custer, Current Development Review Engineer
Minor Site Plan Amendment Comments
5. A guardrail with VDOT designations (GR -2, GR -2a, etc.) is required next to parking or travelways
adjacent to retaining walls or drop -offs of greater than 4 feet, with start and end sections labeled.
18- 32.7.2]
Rev. 1) Comment has not been addressed.
Rev. 2) Comment has not been addressed. Bumper blocks are needed on the parking spaces
southeast of the relocated shed. Guardrails are required where there is a 2:1 slope. For example,
adjacent to the southwest corner of the lower- parking lot and adjacent to the travelway leading up
to the lower parking lot. An alternative to guardrails is to provide 3:1 slopes adjacent to the
parking or travelways.
Rev. 3) Comment has not been fully addressed. Bumper blocks and bollards have been added
to the plan to address concerns at the higher elevation adjacent to the main building. But the
main entry way still possesses side slopes steeper than 3:1. As graded, the slopes must be
protected by a guardrail and planted with a low maintenance, non grass groundcover. If the
slope was graded at 3:1, both requirements would no longer apply and the comment would be
addressed.
Stormwater Management Plan Comments
15. Please address the stormwater management of the concentrated run -off from the proposed pond.
Identify the adequate channel from this site. It appears a drainage easement may be needed from
TMP 32 -22131.
Rev. 1) Comment has not been addressed. Concentrated run-ffrom the proposed pond has not
been addressed. Concentrated run -off appears to be flowing to the neighboring property. Please
identify the adequate charnel from this site. Also, please provide a drainage easement from TMP
32 -22B1.
Rev. 2) Comment has not been addressed. Please provide an adequate channel analysis meeting
Albemarlv - ounty Community Development
Engineering Review Comments
Page 2 of 2
all requirements from the County's Design Manual.
Rev. 3) The submitted channel analysis does not demonstrate to the county that the propertydownstreamofthedevelopmentcontainsanadequatechannel. The n- values used for the
calculations are too large and, therefore, underestimate the calculated velocities (the rangespecifiedinthegreenbookis0.025- 0.223). In addition, due to the characteristics of the stream
cross - section and the nature of the on -site soils as identified by the USDA soil survey, the
permissible velocity of the existing eroded channel is likely 3fps or less. The applicant has 3optionstoremedythiscomment:
1) Make adjustments to the channel analysis bi providing n -value calculations and
permissible and computed velocities for each segment of each channel cross - section (the
deeper, eroded portion of the channel cross - section will have faster velocities than the
section above the banks). If the applicant chooses this option, there is a risk of still having
to proceed to option 2 or 3 if the results of the calculations show an inadequate channel
the two year storm results in eroding velocities and /or the overflowing the channel banks).2) Obtain permanent drainage easements to the culvert underneath Lewis and Clark Drive
and upgrade the channel so that the 2 year velocities are non- erosive and the 10year stormiscontainedwithinthebanksofthechannel.
3) Modify the facility so that the release rates for the 2 and 10 year storms are equal or less
than a forested watershed of the same acreage (0.7cfs and 4.5cfs for the 2 and 10 year
storms). To meet these release rates, the embankment and top of riser would need to be
roughly Ift taller and the Sin orifice would need to be lowered to around the 428 elevation.
Please also provide graded access to the embankment of the facility and a trash rack on the 3in.
orifice. On the 20 scale detail of the plan, please specify the pond plantings for the various
zones of the facility (please see VSMH 3.05).
18. A Stormwater Management bond amount will be computed by the County once the WPO planshavebeenapproved. A completed copy of the standard stormwater management maintenance
agreement and fee for recordation for any stormwater management facilities will be required. [17-304E]
Rev. 3) The SWMportion of the WPO bond has been computed to be $11,800. For questionsregardingthepostingofbonds, please contact Pam Shifflett and 296 -5832 x3246.
19. Please submit a completed copy of the standard Stormwater Maintenance Agreement and fee for
recordation for the proposed stormwater management facilities.
Rev. 3) The agreement has been submitted and it is currently being processed.
29. (Rev.2) Please provide an updated Routing Report after the basin is modified.
Rev. 3) Comment has not been addressed. Please provide a full updated routing report30. (Rev. 2) Please remove the note regarding future stormwater management review. When a future
site plan amendment is submitted, a stormwater management amendment will be required. Or, the
applicant will be required to prove adequacy of the constructed facility.
Rev. 3) Comment has not been addressed Please remove this note.
Erosion & Sediment Control Plan Comments
31. An Erosion & Sediment Control bond amount will be computed by the County once the WPOplanshavebeenapproved.
Rev. 3) The ESC portion of the WPO bond has been computed to be $25,700. For questions
regarding the posting of bonds, please contact Pam Shifflett and 296 -5832 x3246.
Page l of 3
Philip Custer
From: Philip Custer
Sent: Thursday, June 04, 2009 11:55 AM
To: 'JTAGG2 @aol.com'
Cc: Amy Pflaum; John Paul Diez
Subject: RE: Townsend Channel Analysis
Attachments: downstream channel X1.txt; crossection.pdf
Jim,
Engineering has reviewed the latest downstream channel analysis dated 1 June 2009. The computations still
require corrections. I will list these corrections below:
The program used for this computation assumes a uniform n -value across the whole channel cross - section and
computes an average velocity for the entire section. In reality, the water flowing within the banks of the channel
flows much quicker than the water that flows above the banks. Calculations must be provided for each segment
of the channel cross - section (see attached files). These calculations can be done by hand, but there are also
programs available that will do this (I can send you the program that Glenn assembled if needed).
This eroded channel will be reviewed as a natural channel. Therefore, to meet MS -19 requirements, the two -
year storm must both stay within the channel banks and be non - erosive. The 10 -year storm does not need to
meet any capacity or velocity requirements.
You do not need to provide data on the velocities and depths of the channel in the pre - development condition.
We are solely interested in what is happening to the channel after development.
The permissible velocity has not been identified for this eroded channel. Your notes in the back of the analysis
state that the soil is a sandy loam. As identified by Table 5 -22 of VESCH, a sandy loam has a permissible
velocity of 2.5 fps. Velocities within the channel have been computed to exceed this maximum. Please reduce
flows from the basin so that non - erosive velocities are present.
In the future, n- values for each segment of the cross - section should be compiled from Tables 5 -16, 5 -17, 5 -18,
5 -19, 5 -20, and 5 -21. 1 have checked these tables and the use of 0.05 as an n -value within the eroded channel
is reasonable.
Thanks, Phil
15. Please address the stormwater management of the concentrated run -off from the proposed pond. Identify
the adequate channel from this site. It appears a drainage easement may be needed from TMP 32 -22B1.
Rev. 1) Comment has not been addressed. Concentrated run-of .f from the proposed pond has not been
addressed. Concentrated run -off appears to be flowing to the neighboring property. Please idento, the
adequate channel from this site. Also, please provide a drainage easement from TNIP 32- 22131.
Rev. 2) Comment has not been addressed. Please provide an adequate channel analysis meeting all
requirements from the County's Design Manual.
Rev. 3) The submitted channel analvsis does not demonstrate to the county that the property
downstream of the development contains an adequate chanteL The n- values used_for the
calculations are too large and, therefore, underestimate the calculated velocities (the range specdfled
in the green book is 0.025- 0.223). In addition, due to the characteristics of the stream cross- section
and the nature of the on -site soils as identified by the USDA soil survey, the permissible velocity of the
existing eroded channel is likely 3fps or less. The applicant has 3 options to remedy this comment:
1) Make adjustments to the channel analysis by providing n -value calculations and permissible and
computed velocities for each segment of each channel cross - section (the deeper, eroded portion of
the channel cross - section will have faster velocities than the section above the banks). If the
applicant chooses this option, there is a risk of still having to proceed to option 2 or 3 if the results
9/21/2009
Page 2 of 3
of the calculations show an inadequate channel (the two year storm results in eroding velocities
and /or the overflowing the channel banks).
2) Obtain permanent drainage easements to the culvert underneath Lewis and Clark Drive and
upgrade the channel so that the 2 year velocities are non- erosive and the 10 -year storm is
contained within the batiks of the channel.
3) Modify the facility so that the release rates for the 2 and 10 -year storms are equal or less than a
forested watershed of the same acreage (0.7cfs and 4.5gfs for the 2 and 10 year storms). To meet
these release rates, the embankment and top of riser would need to be roughly Ift taller and the
3in orifice would need to be lowered to around the 428 elevation.
From: JTAGG2 @aol.com [mailto:3TAGG2 @aol.com]
Sent: Tuesday, June 02, 2009 5:00 PM
To: Philip Custer
Subject: Re: Townsend Channel Analysis
Thanks Phil. I used Hydroflow Express to solve the composite "n ". That is based on HEC -RAS Eqn. 2.6 and
applies that composite roughness over the wetted perimeter. Therefore the roughness coefficient varies with the
flow. As far as the source of the "n ", I used the Blue Book and assigned as uniform on the side slopes but
different than the channel.
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361 1215
In a message dated 6/2/2009 4:53.21 P.M Eastern Daylight Time, pcuster@albemarle.org writes.
Thanks Jim. I've been pretty swamped the last couple days but I hope I'll get the chance to review the
document you sent tomorrow. If you have any of the other items or if you want to rework something in
the channel analysis, email it to me now. For instance, one of my comments would likely be asking how
you computed the n value (n1 +n2 +n3 +n4 +n5) to be 0.05 and 0.075 for the bottom and sideslopes (if it
is explained in the narrative, disregard this sentence).
From: JTAGG2 @aol.com [mailto:]TAGG2 @aol.com]
Sent: Monday, June 01, 2009 4:29 PM
To: Philip Custer
Cc: jay @townsendlandscape.com
Subject: Townsend Channel Analysis
Phil,
Attached is a revised channel analysis for Jay Townsend's project with revised roughness coefficients
I thought we could work through the remaining issues as you mentioned.
In general I used n =0.05 for the bottom of the swale and 0.075 for the sides. I have included a
summary chart of each section; pre and post developed for 2 year velocity and 10 year depth and top
width.
I'm hoping we can settle on the downstream dilemma and then wrap up the few remaining plan issues
Let me know your thoughts.
JT
Thank You,
9/21/2009
Pagel of 4
Philip Custer
From: Mark Graham
Sent: Friday, June 19, 2009 4:10 PM
To: Philip Custer
Cc: Amy Pflaum
Subject: RE: Townsend Landscaping
Thanks Phil,
With your calcuations on the relative volume, you are hitting on the big problem with cisterns and I'll be the first
to admit that part of this is experimenting. The County Board (2 members in particular) really want to promote
this type of reuse, but as best I can tell, nobody has really figured it out. The flaw ssems to be tht the ideal is
not to water your plants the day after it rains but a week or more after it last rained. So, how much drawdown
do you assume in the design volume of the cistern? it's interesting to see the draft guidance suggesting a
40% runoff reduction rate with these BMPs without addressing the drawdown question.
htt / /WwA . v vt. edu/ swc/ do g /Draft %20DCR6Verl. pdf
I'll add one other factor in my thinking that I didn't put in this draft. Namely, the downstream property is a 5 acre
undeveloped lot in the North Fork Research Park that is assessed at $1.5 Million. As the Foundation is paying
the County over $10K a year in property taxes for this undeveloped lot, I know their intention is to fully develop
this lot as soon as the market allows. That might be next year, it might be 10 years, but eventually it is going to
have a storm sewer across it and the whole outfall issue goes away. So, knowing the Foundation is not even
slightly interested in encumbering their lot with a drainage easement at this time, knowing this swale will end
up in a storm sewer, and knowing this is not going to be a situation where the downstream property owner is
concerned with harming their property, I'm willing to take a risk and experiment a little here.
From: Philip Custer
Sent: Friday, June 19, 2009 11:41 AM
To: Mark Graham
Cc: Amy Pflaum
Subject: RE: Townsend Landscaping
With the adjustments I recommended (raising the top of riser /embankment 1 ft and lowering the orifice to 428),
the two and ten year storms are 0.4 cfs and 4.8 cfs, respectively. Noting that because the channel is not
manmade, the two year storm is all we need to concern ourselves with regarding velocity and capacity and this
two -year discharge is acceptable for both.
However, when I take out the orifice and route it (simulating the summer scenario), I get two -year critical storm
discharges of 1.7, 4.5, 9.6 cfs for situations when the basin is empty, half empty, and full. All of these
discharges would damage the channel, according to manning's calculations, and probably not be in compliance
with 17 -314. 1 understand your argument that be keeping a provision of inspection of the downstream channel
there is less of a long -term risk, but it still implies that there is erosion concern and I would not feel comfortable
approving it. So, I'd like to take you up on your offer to approve the plan.
Please note there are a few other loose ends on the project that were listed in my last letter. Let me know if
you want to me to review those items still or if you will take care of them when receiving Jim's resubmittal.
On a side note, I believe DCR is concerned with the drawdown for Rainwater harvesting. My friend Alex at
McKee Carson is contracted by the Center for Watershed Protection putting together some technical criteria for
A/? 1 0009
Page 2 of 4
just that. Though, it's at the preliminary stage right now and needs to be reviewed by CWP and DCR before it
would ever get into the manual.
son
From: Mark Graham
Sent: Friday, June 19, 2009 9:19 AM
To: Philip Custer
Subject: RE: Townsend Landscaping
Phil,
I'm still trying to find a win -win. Would you look at the following and let me know if
you have concerns with proceeding in this way? I would not expect you to sign -off on
this solution unless you find it acceptable. I would be willing to sign off if you have
concerns with this. (p.s. I've been looking at the use of cisterns under DCR's
proposed regs. I note they still appear silent on rate of use of the water in the cistern.
Has me scratching my head on their use, but I believe this is consistent with their
intent.)
Jim,
I have now reviewed all of the data, revisited MS -19 with DCR, and conducted a site
inspection of the outfall between the Townsend site and Lewis and Clark Drive. I've found
that Phil is correctly interpreting the requirements and providing as much flexibility as
possible while being able to defend our position with DCR. I've also found this outfall area is
in transition with increased erosion likely even if nothing is changed on the Townsend site.
Basically, a conundrum.
That said, I am sympathetic to Mr. Townsend's interest in reducing water demand and
promoting on -site reuse, which are goals the County supports and DCR supports in theory.
As such, I am suggesting a compromise. I would support modifying the outlet structure and
dam height as Phil recommended (To meet these release rates, the embankment and top of riser would need to
be roughly Ift taller and the 3in orifice would need to be lowered to around the 428 elevation.) but I will Offer one
additional concession. Recognizing Mr. Townsend's water reuse is needed in the summer months, I
would allow him to cap this lower orifice during the months of May through September in order to
maximize storage. We will then observe the downstream area over the next several years and if we
find the erosion has become excessive, we would require this orifice to be kept open even in the
summer.
I believe the following are important points to recognize with this compromise.
1. Even with the orifice at elevation 428, it appears Mr. Townsend's storage will meet his
requirements. We are allowing the greater storage during the summer months when his
need is highest.
2. We can show DCR we are maintaining compliance with outfall requirements, thus not
violating the conditions of our storm sewer permit and risking significant fines.
3. If the downstream property owner (UVa Foundation) complains that their property is
being damaged and we find the erosion has accelerated, we can reduce the impacts by
requiring the orifice at elevation 428 be left open throughout the summer.
I hope this provides a solution that can work for everyone. If you have any questions, please
9/21/2009
Page 3 of 4
let me know.
From: JTAGG2 @aol.com [mailto:3TAGG2 @aol.com]
Sent: Wednesday, June 17, 2009 10:02 AM
To: Mark Graham
Cc: jay @townsendlandscape.com
Subject: Re: Townsend Landscaping
Mark,
One aspect of this must issue be the application of the limits of study. Admittedly, with this project we are
currently looking at the area just downstream of our project, although Phil and Amy have both indicated that the
County expects us to analyze cross - sections down to the 1 % level. Nonetheless, there comes a point at which
we can't make effective changes to a watershed when we only have control of the upper reaches. I do not
believe that the channel we have analyzed has experienced the clear signs of erosion you mentioned, and
even if it has, our proposed attenuation of the runoff will certainly help. I think that the proposal we have
offered including the study meets the intent and letter of MS -19 and Tech. Bulletin 1; specifically as it applies to
the use of engineering judgement in these matters.
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
In a message dated 6/17/2009 9:09:46 A.M. Eastern Daylight Time, mgraham @albemarle.org writes:
Jim,
I hope to get this finished by tomorrow. I need to review this with Phil.
DCR did get back with me and said that it appears Phil is correctly applying the state regulations.
I did a site inspection yesterday, but was not encouraged by what I saw on the downstream property.
There are clear signs that the downstream area is already starting to erode.
From: JTAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Tuesday, June 16, 2009 8:02 AM
To: Mark Graham
Cc: jay @townsendlandscape.com
Subject: Townsend Landscaping
Mark,
Following up on the Townsend offsite channel issue. You mentioned Wednesday that you felt close to
a positive resolution. We are hoping to get Phil's final approval this week. Any thoughts?
JT
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
An Excellent Credit Score is 750. See Yours_ in Just_ 2. EasySter)s!
9/? 1 /? 009
Pagel of 2
Philip Custer
From: Mark Graham
Sent: Friday, July 24, 2009 5:15 PM
To: JTAGG2 @aol.com
Cc: jay @townsendlandscape.com; Philip Custer
Subject: RE: Townsend
Jim,
With respect to #1, 1 believe it could work to change the arrangement, though I wonder if it wouldn't be better to
keep the 8" pipe and put a reducer on the upstream end so you have the flexbility to change this design if
needed. Also, with this arrangement I get concerned with the outfall so far up the backside of the dam. I
recommend you take a look at how you are preventing erosion of the dam if that becomes a primary outfall. .
With respect to #2, 1 think you've correctly stated the goal by saying it will meet all 3 criteria.
With respect to #3, 1 am not comfortable with this change. The 3 remaining months are the ones with the
smallest incidents of design storms and when there is no chance of vegetation recovering as a result of
downstream erosion. Also, in picking May through September I was trying to balance the peak months needed
for irrigation with the peak capacity. By April or October, the evaporation rates are half of July- August and we
are outside of the peak period for dry spells. Mr. Townsend would still have the storage capacity at the orifice
elevation for the remainder of the year and I understood this exceeds his minimum design criteria.
From: JTAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Monday, July 13, 2009 2:04 PM
To: Mark Graham
Cc: jay @townsendlandscape.com
Subject: Re: Townsend
Mark,
Thank you for your response regarding the Townsend Pond design. You are correct. I misread the Channel
Adequacy section of the statute. You are also correct that the third criteria is difficult to achieve. I believe I
have met the criteria for the first two items and even satisfied the third with respect to the 1.5 and 2 year
events. Even reducing the receding limb factor (for drainage area hydrographs) from 1.67 (which is my typical
value) to 1.5 as listed in the Virginia Stormwater Management Handbook, the ten year event volumetric
reduction proved problematic with my current pond configuration. The prospect of regrading the pond remains
unappealing because of the grading buffer. I do believe however, that your compromise is valid and would
propose the following:
1. The design has always included a secondary outlet structure (8" Agridrain weir type, water level and drain
structure). Since we are discussing the possibility of closing our BMP orifice for certain portions of the year, it
would be beneficial to utilize this weir structure as both the water quality orifice AND the water level control
structure. To that end, I would like to reduce the size of that outlet structure from 8" to 3" and altogether
remove the proposed 3" orifice from the riser.
2. The drain elevation would be lowered to provide the volumetric increase needed to satisfy all three criteria
set forth in the DSM (as discussed above). This should be attainable without regrading the dam.
3. The closure of the BMP orifice (or drain) during the company's peak water usage months is very desirable. I
have asked Mr. Townsend to review his water needs in that regard. His desire is to expand the timeframe you
mentioned in your email to include the months of March through November. The months at each end of the
annual growing season are critical periods, necessary to his irrigation usage. Therefore we would ask that from
01 MAR until 30NOV each year, the weir plates would be in place at the discretion of Townsend Landscaping to
allow maximum water retention (for irrigation usage) up to the riser's top. For the annual three month period
from 01 DEC until 01 MAR, the weir plates would be removed to lower the normal pool to the prescribed
elevation (to be determined from item 2).
If we agree these items are acceptable in principal, I would suggest that Phil and I could work out the elevation
9/21/2009
Page 2 of 2
of the drain as described above. As I read § 10.1 -561, this would satisfy any question of the downstream
channel adequacy and we could end the discussions of the downstream channel. Further, we could resolve
the last few items he issued regarding the site plan and we could hopefully build this project this fall.
Thoughts?
JT
Thank You,
Jim Taggart, RE
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
Looking for love this summer? Find it now on AOL Personals
9/21/2009
Pagel of 2
Philip Custer
From: Philip Custer
Sent: Tuesday, August 18, 2009 11:20 AM
To: 'JTAGG2 @aol.com'
Cc: Mark Graham; Amy Pflaum
Subject: RE: Townsend
Jim,
I have reviewed the Routing and CAD details you sent me yesterday. I have the following comments:
The 4" orifice does not meet the drawdown requirements for an extended detention facility. My calculations
indicate that a 1.5in diameter orifice is required. But, since a 3" orifice size is recommended by the VSMH as
the smallest allowable, we should adhere to their standard.
The critical storms were not routed. Storms of longer lengths longer and lower intensities than the storms
routed in the calculations will produce higher outlet discharges.
The plan still requires a specification regarding the planting of the area to be inundated.
In a previous email, you mentioned that you were reluctant to raise the dam elevation because of the 30ft
undisturbed buffer along the boundary line with the property zoned Residential. A few weeks ago, Mark and I
looked through the old SP and ZMA files in addition to reading the minutes from the board meeting and could
not find any reference to a 30ft undisturbed buffer. Our current ordinance requires a 20ft buffer for situations
such as this. Where did you get this requirement from?
Please let me know if you have any questions.
Thanks,
Phil
From: JTAGG2 @aol.com [mailto:3TAGG2 @aol.com]
Sent: Monday, August 17, 2009 10:46 AM
To: Philip Custer
Subject: Re: Townsend
Must not have gone through... trying again.
Thanks
JT
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
In a message dated 8/17/2009 10:44:02 A.M. Eastern Daylight Time, pcuster @albemarle.org writes:
Is there a 1 of 3? 1 have received 2 of 3 and 3 of 3 with 1 attachment each.
From: JTAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Monday, August 17, 2009 10:02 AM
To: Philip Custer
Subject: Re: Townsend
9/21/2009
Page 2 of 2
part 3 of 3
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
In a message dated 8/17/2009 8:57:04 A.M. Eastern Daylight Time, pcuster@albemarle.org writes:
For some reason, the attachment did not come through. The county server may be blocking
all .zip files. Is there any way you can send me .pdfs without the zip?
From: JTAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Monday, August 17, 2009 7:50 AM
To: Philip Custer
Cc: jay @townsendlandscape.com
Subject: Re: Townsend
Phil,
Routings and pond drawings as requested. 3" BMP orifice has been removed and the 8"
drain has been reduced down to a 4" with a trash screen at elev. 428.
For those months when the drain is closed (water is stored to top of riser @431) the 100 year
event tops out 0.4' below the emergency spillway. During those months when the drain is
open (winter months @ 428.0) the 100 year event rises to just below the riser top.
Emergency spillway is not utilized during the 100 yr. event therefore freeboard is not an issue.
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
9/21/2009
Page 1 of 1
Philip Custer
From: Philip Custer
Sent: Monday, August 24, 2009 2:37 PM
To: 'JTAGG2 @aol.com'
Cc: Amy Pflaum
Subject: RE: Townsend
The critical duration should be found during the routing of the pond by the program. Most routing software has
the ability to do this. If Hydraflow does not, the critical duration can be discovered manually by entering greater
durations of rainstorms until you find the duration when the routed discharge decreases.
Equation 5 -5 can be used to find the approximate area to start at when looking for the critical storm, but it
should not be assumed to be 100% accurate. In this situation, the "pre - development rates" used in Equation 5-
5 should be 0.7cfs and 4.5cfs (SCS forested rates) because of the lack of adequate channel downstream.
Please route the pond from the 428 elevation to simulate rain events during the winter months with the 2ft
sump full of water.
If you raise the elevation of riser, emergency spillway, and top of dam 1ft, it should work
Please call if you have any questions.
Phil
434) 296 -5832 x3072
From: JTAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Thursday, August 20, 2009 9:29 AM
To: Philip Custer
Subject: Townsend
Critical durations 2, 10, 100 yr.
Routings 2, 10, 100
pond section
outlet reduced to 3"
Thank You,
Jim Taggart, P.E
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
9/21 /2009
Pagel of 2
Philip Custer
From: Mark Graham
Sent: Tuesday, September 08, 2009 9:36 AM
To: Philip Custer
Subject: FW: Townsend
FYI,
From: JTAGG2 @aol.com [mailto:JTAGG2 @aol.com]
Sent: Tuesday, September 08, 2009 7:23 AM
To: Mark Graham; jay @townsendlandscape.com
Subject: Re: Townsend
Mark,
Thank you. I will change the elevations, regrade the back of the dam, and revise the buffer as directed.
Please ask Phil to let me know how many sets to send in for signatures.
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
In a message dated 9/4/2009 4:48:29 P.M. Eastern Daylight Time, mgraham @albemarle.org writes:
Jim,
I finally sat down with Phil and walked myself through all of this. I will approve this with the elevation of
the dam raised 1' and the elevation of the riser raised 1'. For the dam, I have confirmed this is a 20'
buffer, meaning we can allow the slope for the 1' extra dam height to be taken up on the downstream
side and avoiding the need to move the dam.
If you are OK with these changes, I will go ahead and conditionally approve the plan, noting those 2
changes as conditions of the approval.
Phil also has a concern with the type of vegetation in the area that will fluctuate between wet and dry.
I'm saying our isnpectors can can work that out in the field with Jay Townsend as part of establishing
permanent vegetation when the construction winds up.
Have a good weekend,
Mark .
From: Jim Taggart [mailto:jtagg2 @aol.com]
Sent: Friday, September 04, 2009 7:48 AM
To: Mark Graham; jay @townsendlandscape.com
Subject: Townsend
Mark,
Following up on the Townsend issue.
Thank You,
9/21 /7009
Page 2 of 2
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
434 - 361 -1215
9/21/2009
Page 1 of 2
Philip Custer
From: Philip Custer
Sent: Wednesday, September 09, 2009 2:06 PM
To: 'JTAGG2 @aol.com'
Cc: Mark Graham, Bill Fritz; Amy Pflaum
Subject: RE: Townsend
Jim,
For approval, you will need to submit 10 copies of the plan to the county. In addition to raising the embankment
and riser top 1ft, please be sure to include all necessary modifications to address the outstanding comments.
These changes include:
removal of the stormwater note regarding future development;
addition of a note describing the agreement regarding the conversion of the extended detention facility into a
cistern for May through September, inclusive;
addition of guardrail at the entry drive and low maintenance, non -grass groundcover over the 2:1 slopes or
regrading to create 3:1 slopes; and
addition of a note near the facility stating that BMP plantings to be coordinated with ESC and SWM inspectors
Please let me know if you have any questions
Thanks,
Phil
From: Mark Graham
Sent: Tuesday, September 08, 2009 9:36 AM
To: Philip Custer
Subject: FW: Townsend
FYI,
From: JTAGG2 @aol.com [mailto:3TAGG2 @aol.com]
Sent: Tuesday, September 08, 2009 7:23 AM
To: Mark Graham; jay @townsendlandscape.com
Subject: Re: Townsend
Mark,
Thank you. I will change the elevations, regrade the back of the dam, and revise the buffer as directed.
Please ask Phil to let me know how many sets to send in for signatures.
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
ph. 434.361.1215
In a message dated 9/4/2009 4 P.M. Eastern Daylight Time, mgraham @albemarle.org writes:
Jim,
9/21/2009
Page 2 of 2
I finally sat down with Phil and walked myself through all of this. I will approve this with the elevation of
the dam raised 1' and the elevation of the riser raised 1'. For the dam, I have confirmed this is a 20'
buffer, meaning we can allow the slope for the 1' extra dam height to be taken up on the downstream
side and avoiding the need to move the dam.
If you are OK with these changes, I will go ahead and conditionally approve the plan, noting those 2
changes as conditions of the approval.
Phil also has a concern with the type of vegetation in the area that will fluctuate between wet and dry.
I'm saying our isnpectors can can work that out in the field with Jay Townsend as part of establishing
permanent vegetation when the construction winds up.
Have a good weekend,
Mark .
From: Jim Taggart [mailto:jtagg2 @aol.com]
Sent: Friday, September 04, 2009 7:48 AM
To: Mark Graham; jay @townsendlandscape.com
Subject: Townsend
Mark,
Following up on the Townsend issue.
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
434 - 361 -1215
9/21/2009
Page 1 of 4
Philip Custer
From: Jim Taggart Dtagg2 @aol.com]
Sent: Tuesday, September 15, 2009 11:36 AM
To: Mark Graham; Philip Custer; jay @townsendlandscape.com
Subject: Re: Townsend
ok
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
434 - 361 -1215
Original Message---- -
From: Mark Graham <mgraham(aalbemarle.org>
To: Jim Taggart <jtagg2 @aol.com >; Philip Custer <pcuster(aalbemarle.org >;
jay@townsendlandscape.com
Sent: Tue, Sep 15, 2009 11:27 am
Subject: RE: Townsend
I'm sorry to step in at this point Jim, but I dont' believe saying the owner "will work with County inspectors" is
adequate. In the event downtstream problems are aggrevated, either the County has the ability to require the
elevation kept at 428.0 or it doesn't. As I pushed this compromise with the idea we had a fallback if we found this
isn't working, I believe the last sentence should read:
Should County inspections determine that downstream erosion has been aggrevated following
completion of the dam, the County may require the weir plate to be removed or adjusted down to elevation
428.0. "
That gives the County a fallback position but also holds open the possibilty of a future revision should this design
prove to aggrevate the downstream erosion.
From: Jim Taggart [ mailto:jtagg2()aol.com ]
Sent: Tuesday, September 15, 2009 11:01 AM
To: Philip Custer; Mark Graham; jaMtownsendlandscape.com
Subject: Re: Townsend
Great. I'll revise and resubmit tomorrow. Is there a fee, transmittal or application with the 10 copies?
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
9/21/2009
Page 2 of 4
Faber, VA 22938
434- 361 -1215
Original Message---- -
From: Philip Custer < pcuster -a( arle.o
To: Jim Taggart < >; Mark Graham < mgraham (cr),albemarle .or2 >;
jay cr tovmsendlandscape.com
Sent: Tue, Sep 15, 2009 10:54 am
Subject: RE: Townsend
ok
From: Jim Taggart [ mailto Jtagg2Ca)aol.com
Sent: Tuesday, September 15, 2009 10:50 AM
To: Philip Custer; Mark Graham; jay_atcwnsendlandscape.com
Subject: Re: Townsend
Phil,
I don't read anything in Mark's 19JUN email about staff having the right to require "any modification
they deem appropriate" based on really any condition they may decide. I think the litmus test is the
County inspectors or downstream owner issuing a complaint of accelerated erosion, and the remedy
would be to adjust the weir plate. Regarding any perceived detention or water quality
issues, the County's remedy should be no different from that of any other facility in the County. If the
County has that ability, it would be within the powers of the maintenance agreement. If so, let's leave it
there for this project as well. I suggest we do this:
Stormwater Management Pond Operations Schedule:
from 01 MAY through 01 OCT each year, the BMP orifice (3" orifice at elevation 428.0) is to be closed with th e expectation
that any water collected within the facility will be reused as irrigation by the landowner. The weir plates on the Agridrain (R)
structure will be installed up to elevation 432.0. During the colder months (01 OCT -01 MAY) the weir plates shall be removed
down to the 428.0 elevation to allow large storm storage. Should downstream channel inspection raise concerns of increased
or accelerated erosion, the owner will work with County inspectors to adjust the weir plates to alleviate the problem.
Regarding the plantings, I will add the note about the submerged area.
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
434- 361 -1215
Original Message---- -
From: Philip Custer < >
To: Jim Taggart < jtagg2 a,aol.com>
Sent: Tue, Sep 15, 2009 10:18 am
Subject: RE: Townsend
Jim,
9/21/2009
Page 3 of 4
I have no problem with the text revisions to 1 and 3.
For 2, to reflect some of the statements in Mark's June 19t email, please add the following sentence to the end:
If future County inspection finds issues with the facility's success regarding detention, water quality treatment, or
excessive erosion downstream, the County reserves the right2Oto require the BMP to be converted to an
extended detention facility permanently and any other necessary modification deemed appropriate by county staff
at that time."
Regarding 4, the plantings you have specified appears to meet VSMH standard 3.05. However, landscaping
below the 432 elevation in the pond is not specified. The landscaping in this area will need to be tolerant of
ranges from 4ft of submergence to extensive dry conditions. Though Table 3.05 -4b does not list a species that
includes zones 1, 2, and 3, Duckweed seems to be the planting best suited for this area. Though, I'm open to any
other plant not listed in that tab le as long as there is evidence supporting its ability to live in all conditions
anticipated for the pond, or a general note stating that this area is to be worked out w ith the ESC and SWM
inspectors.
Phil
0 D
From: Jim Taggart [ mailto Jtagg2(Qbaol.com
Sent: Monday, September 14, 2009 2:00 PM
To: Philip Custer
Cc: Mark Graham; Bill Fritz; Amy Pflaum; iay@townsendlandscape.com
Subject: Re: Townsend
Phil,
Thanks. Here are the text20revisions to your comments. If you agree with these, I'll send in the copies.
removal of the stormwater note regarding future development;
As I mentioned, 1 think it is important to outline what was considered within the ultimate buildout design. Here's
the note:
Stormwater Management =2 OFuture Buildout:
This current amendment includes a building addition as well as expanded parking areas for business operations and
employee parking. It is expected that the site will eventually include an additional 7,000 s.f. parking area (see future
parking) and additional 3,000 s.f. building footprint(s). The =2 Ostormwater management basin, along with drainage
imp rovements have, in accordance with Virginia E &S Code and Stormwater Management codes, been designed to
mitigate the current improvements and the additional 10,000 s.f. of parking area and building footprint. This
additional impervious area represents potential future improvements that will be considered under a future and
separate site plan application."
addition of a note describing the agreement regarding the conversion of the extended detention facility into a
cistern for May through September, inclusive;
Stormwater Management Pond Operations Schedule:
from 01 MAY through O1 OCT each year, the BMP orifice (3" orifice at elevation 428.0) is to be closed with the expectation
that any water collected within the facility will be reused as irrigati on by the landowner. The weir plates on the Agridrain (R)
structure will be installed up to elevation 432.0. During the colder months (01 OCT -01 MAY) the weir plates shall be removed
down to the 428.0 elevation to allow large storm storage.
addition of guardrail at the entry drive and low maintenance, non -grass groundcover over the 2:1 slopes or
regrading to create 3:1 slopes; and
Slopes approaching roadway have been flattened to 3:1)
addition of a note near the facility stating that BMP plantings to be coordinated with ESC and SWM inspectors.
0 A
Pond perimeter(3 ft. from normal pool line) and along inflow channel to be planted as water Quality
9/21/2009
Page 4 of 4
Zone 3 -4. Use Broomsedge (Andropogon virginianus) around perimeter and Switchgrass (Panicum
Virgatum) in and around rip rap channel approaching pond or as agreed by owner and E &S inspectors.
There shall be no zone 2,5, or 6 areas within this structure.
Sediment Forebay to be planted as water Quality Zone 1. Use Coontail (Ceratophyllum demersum) or
pond Weed (Potamogeton pectinatus) or as agreed by owner and E &S inspectors.
Thank You,
Jim Taggart, P.E.
for TCS Engineering Co., LLC
741 Duncan Hollow Loop
Faber, VA 22938
434 - 361 -1215
9/21/2009
Page I of I
Philip Custer
From: Philip Custer
Sent: Monday, September 21, 2009 9:39 AM
To: jay @townsendlandscape.com; 'Jim Taggart'
Cc: Bill Fritz; Mark Graham
Subject: Engineering Approval of JW Townsend site expansion project (SDP -2008 -00081 and WPO -2008-
00088)
Good afternoon,
Engineering has reviewed the latest submittal for the JW Townsend site expansion project (SDP- 2008 -00081 and
WPO- 2008 - 00088), received on 16 September 2009. The Erosion & Sediment Control and Stormwater
Management Plans are hereby approved. In addition, all site plan comments have been addressed and engineering
review offers no objection to the approval of the minor amendment.
The stormwater and erosion and sediment control bonds have been recalculated since May due to
new state legislation being passed in July and minor changes in the design. The E &SC bond
amount is $26,000. The SWM bond amount is $18,900. The forms and instructions to post the Water
Protection Ordinance Bond can be found on the Community Development Department Web site on
Nyw , A.al_hemarle..org. You may contact Pam Shifflett (Albemarle County Department of Community
Development) at ext. 3246 for further information on bonding procedures.
Once the E &SC bond and the SWM bond have been posted and the site plan amendment approved, you may
contact the Department of Community Development to arrange a pre - construction meeting with a County Erosion
Sediment Control Inspector. Should the County Inspector find the limits of disturbance increased or the need
for additional control measures required to protect the site, additional fees will be required.
Please contact me should you have any questions.
Thanks,
Phil
9/21/2009