Gateway BP(1.4)-CS010322· ,, Halff Associates
Ill
ENGINEERS · ARCHITECTS · SCIENTISTS
PLANNERS · SURVEYORS
8616 NORTHWEST PLAZA DRIVE
DALLAS, TEXAS 75225
(214) 346-6200
FAX (214) 739-0095
Mr. Michael A. Martin, P.E.
City of Coppell
255 Parkway Boulevard
P.O. Box 478
Coppell, Texas 75019-4409
March 22, 2001
AVO 19266
RE: Gateway Business Park Lot 1R? Havert~'s Drainage Improvements and Exchange Circle
Reconstruction
Dear Mr. Martin,
HalffAssociates has reviewed the City of Coppell of comments to the referenced plans and proposes to
address comments 2 and 13 as follows. Subject to the City's approval.
2. Provide junction boxes and manholes as indicated on sheet STM-1.
Provide precast¢ concrete Tee Manholes (see attached diagrams) at locations indicated on sheet STM-
13. The proposed cul-de-sac should be designed so that the middle is the high point and drainage
occurs adjacent to the curb (see sheet GR-1).
The proposed cul-de-sac ties into the existing pavement at elevation 521.99 ft and at elevation 521.31
ft. In order to have drainage occur adjacent to the curb of the cul-de-sac and match existing pavement
at the road would require a slope of approximately 0.35% along the curb line of the cul-de-sac. Halff
Associates recommends a minimum of 0.5%. There fore we propose that drainage occur along the curb
line of the existing road, as shown on sheet GR-1. In addition, there will be a future driveway at the
east side of the cul-de-sac as part of future development
Please provide guidance as to above proposals.
If you have anv questions please oontact Martv Pari~ or mvselr
S~cerely,' ~ ....
TRANSPORTATION o WATER RESOURCES · LAND DEVELOPMENT · MUNICIPAL · ENVIRONMENTAL · STRUCTURAL
MECHANICAL · ELECTRICAL · SURVEYING ° GEOGRAPHIC INFORMATION SYSTEMS
ARCHITECTURE · LANDSCAPE ARCHITECTURE · PLANNING
Frame & Cover
(By Others as Req'd.) ~
Adjustment Ring(s)
Flat Slab Top/~i}[~'~
Riser(s)
48"
Transition Slab Transition Cone, Base Se~ioq
11
Large Diameter" ~ ~ ~ MH Tee
Base Section ~ ~
~OtO: -~o 8o~l~-
Manhole steps are available as required. ~ All dimensions subje~ to allowable
InveRs and resilient connectors furnished as required, s~cifi~tion tollemn~s.
~ SE~ON.PAGE DATE
~recast Manhole Assembly Diagram 4.~ o-~-oo ~H~~O~
(Precast) Manholes
..... ~::i~i:. ~ '~ o ~
Plan View s,~,, Offset,Jaint: ; : Confined Groove Joint
Bend x Tee Manhole (Lay Hight)
~~il~ E
r-
'1. Laying Length
Plan View
Tee Manhole Side View
Tee Manhole
.:: ::i:: t:::~: :
~ ~ E
Plan View
Bond x Too Manhole (Lay I_eft)
~aanhole Steps are available as required. -No Sc, ale-
Usual riser diameter is ~' but riser diameter All dimensions subject to allowable
equal to line pipe diameter is possible, specification tollerances,
TITLE SECTION.PAGE DATE
Tee-Type Manhole Assembly 4.4 8-~-00 li~"Ha~lsor~
72,, Line Size & Larger
Mr. Marty Paris, P.E.
Halff Associates
8616 Northwest Plaza Dr.
Dallas, Texas 75225
FILE
March 19, 2001
Gateway Business Park Lot 1R, Haverty's Drainage Improvements and Exchange
Circle Reconstruction
Dear Mr. Paris:
The City of Coppell has reviewed the referenced plans and has the following comments to
offer:
1. Make changes to title pages as indicated on the plans.
2. Provide junction boxes and manholes as indicated on sheet STM-1.
3. Need to show the distance the proposed 6'x 5' RCB and the 7'x 5' RCB will be placed off
of the lot lines.
4. The minimum grade for 8" sanitary sewer lines is 0.34%.
5. The proposed sanitary sewer manholes should be 5' in diameter.
6. Where the proposed 8" sanitary sewer line meets the existing 12" sanitary sewer, a 5'
diameter manhole should be constructed.
7. A manhole should be constructed at the west end of the proposed 8" sanitary sewer line.
8. Show the location of the proposed 8" sanitary sewer line crossing on the storm sewer
profile "Line A".
9. Provide a detail for the proposed equalizer between the double 7'x 5' RCB.
10. Provide embedment detail for the proposed reinforced concrete box (RCB).
11. Show the location of the proposed 8" sanitary sewer line on the Grading Plan.
12. The curb removal should be sawcut 18" from back of curb.
13. The proposed cul-de-sac should be designed so that the middle is the high point and the
drainage occurs adjacent to curb (see sheet GR-1)
14. To ensure a clear delineation of where Exchange Circle ends and the driveway begins, a
curb return for the existing driveway needs to be constructed (see sheet GR-1).
15. Show the design capacity of the proposed drainage system on the storm sewer profile
sheets.
255 PARKWAY !~ p.O.IaOX 478 ~r COPPELL TX 75019 ~' TEL 972/462 0022 'tlr FAX 972/304 3673
There are various other minor comments throughout the plans. When all comments have been
addressed, please return these marked plans and two sets of revised plans to the City for
review. If you have any questions, please contact me at (972) 304-3681.
P.E.
Assistant City Engineer