Coppell Ind 2-CS040506 (2)·'". Halff Associates, Inc.
ENGINEERS ARCHITECTS SCIENTISTS PLANNERS SURVEYORS
4000 Fossil Creek Blvd.
For[Worth, Texas 76137
(817) 847-1422
Metro (817) 429-9975
Fax (817) 232-9784
Letter of Transmittal
TO:
FROM:
Email:
Keith Marvin, P.E.
City of Coppell - Engineering
255 Parkway Boulevard
Coppell, TX 75019
Stephen Crawford, PE
scrawford@hal ff. com
DATE: May 6, 2004
AVO: 21446
PROJECT: Tradepoint Grading &
Erosion Control Plan
THESE ARE TRANSMITTED as checked below:
[] For approval [] As requested
[] For your use [] For review/comment
ITEMS SENT:
5 Copies of Grading Plan and Erosion Control Plan for Tradepoint Business Park
COMMENTS:
Keith,
We have addressed your comments on the enclosed plan. We previously prepared a detention analysis on the
proposed ultimate development of the Tradepoint site. The ultimate detention layout will be a linear pond
along the east side of the site. The existing ditch running along Bethel will be covered during the final
building construction, but not at this time.
Also, this mass grading plan will not affect the drainage on the existing property (primarily because we are
leaving the existing ditch in place along Bethel). The area that you marked on the plans showing your concern
drains a small area (approx. 5 acres). According to the new iSWM Manual, the intemeptor swale should be
able to contain the 2-year runoff event with a maximum depth of 1.5 feet. The existing ditch north of the
existing Building I will have enough capacity to contain this depth and more. The remaining swales are
adequately sized to contain the 2-year runoff as well.
I am submitting these plans separately from Hillwood's submittal. Hillwood will be submitting the NOI, the
inspection fee, the Early Grading Permit application form, and a "hold harmless" letter. I am submitting 5
copies of the plan (3 for the City, I for Hillwood, and I for Haiti). Finally, we have a plat prepared but it has
not been recorded yet. Hillwood is currently working on some issues that may change the plat. I can submit
an unsigned/unrecorded version if requested.
Please let me know if you have any further questions or comments.
SIGNED: Stephen Crawford ~
COPIES: File