Westhaven-CS121221 rian Kimley-Hom December 21,2012,Page 1
and Associates, Inc.
December 21, 2012
•
Mike Garza
Suite 200
City of Coppell 5750 Genesis Court
255 Parkway Blvd. 75034,Texas
75034
Coppell,TX 75019
Re: Construction Plans
Westhaven Phase 1
Dear Mr. Garza:
This letter is in response to your comments on November 26, 2012 and includes
discussions from meeting with Mike Garza on December 3, 2012. The following
items have been addressed as per the referenced review:
1. Cover Sheet: Not pleased with traffic calming.
Response:An additional traffic calming device was installed across
street.
2. Final Plat: Add 15' UE for Waterline.
Response: Waterline at the end of Canterbury Court was connected to
the 12"Waterline within SH 121. 15'UE was added accordingly.
3. Final Plat: How is Sanitary Sewer easement being acquired?
Response:Sanitary sewer easement has already been secured from the
adjacent HOA. Recording information will be included prior to filing
the Final Plat.
4. Final Plat: Add floodplain note.
Response:Floodplain note has been added.
5. Sheet C-6: See City General Notes and refer to standard Coppell details.
Response:City of Coppell notes are for home construction and do not
apply to infrastructure and subdivision construction. General notes,
originally submitted, were maintained and incorporated mark-ups
from the City.
6. Sheet C-7:Add sidewalk along SH 121.
Response:Per meeting with City of Coppell,sidewalks along SH 121
will only be required in far NE corner of Phase 2 to property boundary
(typical).
7. Sheet C-8: Remove additional barrier free ramp in open space..
Response:Additional ramp removed.
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8. Sheet C-9:
a. Note 8 referring to landscape plans, include plans.
Response:Per meeting with City,note is sufficient as the
flatwork limits have been coordinated with the landscape
architect.
b. Pedestrian bridge to be submitted for engineering review.
Response: Will be included at time of landscape submittal.
c. Miscellaneous circles on sheet.
Response:Per meeting with City, no action required.
9. Sheet C-10: Define limits of grading and show trail grading.
Response:Per meeting with City,no action required. Trail will follow
natural ground.
10. Sheet C-11:
a. Pedestrian safety rail needed
Response:Safety rail has been added.
b. Where is section located?
Response:Moved Section X-X to Sheet C-9.
11. Sheet C-12: Pedestrian safety rail needed.
Response:Safety rail has been added.
12. Sheet C-13:
a. Stamped concrete at entry.
Response:Stamped concrete section added(typical).
b. General traffic calming comments.
Response:Additional calming device installed on other side of
street with driveway placements shown. Longitudinal slope
only reduced by 0.05%through section.
c. Valley gutters not permitted.
Response:Per meeting with City,labels misrepresent intent.
Labels removed(typical).
13. Sheet C-14:
a. No Parking adjacent to open space.
Response:Per meeting with City, no action required as parking
is not allowed adjacent to opens spaces per city ordinance.
b. Move barrier free ramp in roundabout to intersection.
Response:Ramp moved.
14. Sheet C-15:
a. Provide TxDot permit.
Response: TxDot set previously submitted and approved by the
City. Will provide approved TxDOT permit to city.
b. Street too steep for crosswalk.
Response:Flatted street slope to 2%through crosswalk area.
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and Associates, Inc.
c. No parking on 18' drive.
Response:Per meeting with City, no action required.
15. Sheet C-16:
a. Label PCR& PCI on plan view.
Response:Per meeting with City,no action required.
b. Where is emergency overflow from low point?
Response:Overflow to East intersection 0.39'& to West
highpoint 1.03'. No action required.
16. Sheet C-17:
a. Visibility triangle in open space.
Response: Visibility easement added.
b. Only one barrier free ramp.
Response:Barrier free ramp removed.
17. Sheet C-18:
a. ADA cross slope.
Response:Flattened street slope to 2%through crosswalk area.
18. Sheet C-19:
a. Barricade type?
Response:Changed to Type Ill barricade.
b. Drainage at end of street.
Response:Added note to see sheet C-28.
19. Sheet C-20:
a. 9' parallel parking width?
Response:Per meeting with City,parallel parking width of 8'.
b. Detail for"No Parking".
Response:No action,per meeting with City.
20. Sheet C-21: No Parking or increase radius.
Response:No action,per meeting with City.
21. Sheet C-22:
a. Increase radius.
Response:No action,per meeting with City.
b. Fix C-6.
Response:Sections changed on Sheet C-6.
c. Slope of alley at intersection.
Response:Alley slope maximized to keep flow in street gutter.
No action required.
22. Sheet C-23:
a. Tc Analysis needed and begin HGL at 100yr Floodplain.
Response:KHA coordinated with USACE to confirm current
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models along Denton Creek Corridor study. On 12/20/12, KHA
provided a copy of the graph indicating peak flows for the
Westhaven Creek("Tributary")and Denton Creek. These peak
values are separated by approximately 90 mins confirming
reduced starting HGL. Additionally, USACE model for CDC
permitting does not include discharge from Lake Grapevine as
the peaking times are too far apart.
b. Too small on grade-to-drain.
Response:Future box culverts shown,per request in meeting
with City.
23. Sheet C-24: Intensities circled.
Response:As discussed in meeting with City, time of concentration for
single family is 15 minutes per the City of Dallas Drainage Manual.
24. Sheet C-25: Tc circled.
Response:No action,per meeting with City.
25. Sheet C-26:
a. Sizes?
Response:Pipe sizes added to plan view(typical).
b. Add w/access to manhole callouts.
Response:Added text to callouts(typical).
c. Show all crossings with sizes.
Response:All crossings with sizes added(typical).
d. What SS line?
Response:Line names added to SS crossings(typical).
e. Can all this fit in a 6' manhole?
Response: Yes. Two lateral connections are 4'above main line
connections. No action.
f. Capacity?
Response:Qcap added to all hydraulic data(typical).
g. Remove street stationing&add pipe stationing.
Response:No action,per meeting with City.
h. Recessed inlets?
Response:No action,per meeting with City.
26. Sheet C-27: Headwall underwater?
Response:No action,per meeting with City. Pipe is submerged and
prevents sediment from clogging pipe.
27. Sheet C-28:
a. Temp drainage.
Response:Rip-rap added to end of street for erosion
protection,per meeting with City.
b. Turn to pond.
Response:No action,per meeting with City in efforts to save
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trees in open space and to follow alignment of future pipe.
c. Pier on headwall.
Response:No action,per meeting with City.
28. Sheet C-29: TxDOT permit
Response:Permit will be submitted to City upon approval.
29. Sheet C-31: 3-grate inlet detail
Response:Detail added to sheet.
30. Sheet C-33:
a. This should be HOA maintained.
Response:Changed drainage easements to private drainage
easements.
b. Use standard headwall on piers.
Response:Proposing alternate deepened footers in lieu of
piers.
c. Headwall underwater.
Response:No action,per meeting with City in efforts to save
trees in open space and to follow alignment of future pipe.
31. Sheet C-37:
a. Add valve.
Response: Valve added.
b. Why are these shown 8'from ROW yet under paving?
Response:Detail modified to reflect correct dimensions
(typical).
c. Loop dead-end line in N Canterbury Court.
Response: Tap to existing line in SH 121 row instead.
d. Loop dead-end line in S Canterbury Court through Alley C.
Response:Extended line beyond row and added note for line to
be extended with Phase 2,per meeting with City.
e. Need blowoff/FH at end of Terrace Street.
Response:Added Fire Hydrant.
f. Label all existing waterline features.
Response:Labels added.
g. Combine into one call.
Response:Callouts combined.
h. Use city details.
Response:Added note to refer to city standard details.
i. Show curve numbers and fitting for curve.
Response:Added paving stations/offsets and curve
information for lines in this area. Updated pipe radius note to
correctly reflect intent.
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and Associates, Inc.
32. Sheet C-38:
a. Add manholes instead of cleanouts.
Response:No action,per meeting with City as distance
requirements meet City design standards.
b. Show stationing of ss lines on plan.
Response:Manhole stationing sufficient,per meeting with City.
c. 12"to 10" reduction.
Response:Size used for slope control only. No action.
d. Manhole needed at PC on Line SS-A.
Response:Manhole moved from sta 23+90.98 to PC location on
line.
e. Phase II easement dedicated now as separate instrument?
Response: Yes. Separate Instrument to accompany plat
submittal.
f. Which manholes are vented?
Response:No action,per meeting with City.
g. Rim elevation above BFE?
Response:No action,per meeting with City as manholes are
sealed and would otherwise be 6'in the air in some locations.
h. Offsite easment.
Response:Easement by separate instrument.
33. Sheet C-39:
a. Show all crossings.
Response:All crossings shown.
b. See detail 5160 Coppell standard detail.
Response:This project required specific aerial design as carrier
pipe was lengthened to reduce piers per the floodstudy.
34. Sheet C-41: Why is water crossing so deep?
Response: Water crossing designed to maintain 2'clearance with
sanitary sewer. Going over sewer line would not provide clearance and
cover over pipe. No action.
35. Sheet C-46:
a. City detail for sign post.
Response:Added note to refer to city standard detail.
b. No parking signs.
Response:Called out on paving plans as stamp. No action,per
meeting with City.
c. Street light at roundabout and overlook.
Response:Street lights added.
d. Move street light from open space to end of cul-de-sac.
Response:Street light moved.
e. Signage at roundabout.
Response: "One-way"signs added.
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36. Sheet C-48: What is the permanent erosion control in this area?
Response:No action,per meeting with City.
37. Sheet C-49: Include wire backing
Response:Replaced current details with city standard details.
Sincerely,
KIMLEY-HORN AND ASSOCIATES, INC.
7/11(.., •
Mark E. Harris, P.E.
Project Manager