Billingsley-CS050705COl'FELL
July 5, 2005
Mark McGraw
Halff and Associates
8616 Northwest Plaza Drive
Dallas, TX 75225
RE:
Billingsley Development / Floodplain Development Permit
(near southwest comer o f Belt Line/M acArthur Blvd.)
Dear Mr. McGraw:
I have reviewed the grading plan submitted for the Floodplain Development Permit in
regard to filling the Billingsley site, near the southwest comer of Belt Line Rd. and
MacArthur Blvd. The area to be filled is in general compliance with the floodplain
information submitted for the CLOMR issued by FEMA on May 25, 2005. However, some
of the details on the drainage leaving the site are not consistent with the Belt Line Rd.
improvement plans, designed by Halff and Associates and recently constructed by Dallas
County.
Prior to approval of a Floodplain Development Pemait to fill this site, the following items
need to be addressed:
Sheet C2.01
1. On Drainage Area A-2, a runoff coefficient of .4 should be used, not ~3. Also, the Belt
Line Rd. plans show a portion of what you show as Drainage Area A-2 being picked up
by the inlet in Belt Line Rd. Your plans propose taking all of Drainage Area A-2 in a
pipe to the east and discharging it into a different drainage pipe.
2. The Belt Line Rd. plans show a portion of Drainage Area A-5 going to the inlet in Belt
Line Rd.
In txvo locations in the Drainage Area labeled A-5, there are ridge lines showing
drainage to break north and south. Howcver, you are showing the entire Drainage Area
A-5 to go north. Please clarify.
The as-built plans for Valley Ranch Plaza show an additional 6.39 cfs draining to the
existing culvert system in Belt Line Rd. This will reduce the available capacity in that
pipe. The Belt Line Rd. plans show that only 67.5 cfs was proposed to go into the
culvert on the south side of Belt Line Rd.
It is my understanding that there will be some changes associated with the grading plans
along the east side of the property based on comments from the City of Irving related to
fill above the existing 54" Irving water main and the 48" DWU water main.
Once these changes have been corrected, please submit revised plans. If you should have
any questions please feel fl'ee to contact me.
Sincerely, .)
Kenneth M. Griffin, P.E.
Director of Engineering and Public Works
Office 972/304-3686
Fax 972/304-7041
E-mail kgriffin@ci.coppell.tx.us
HP LaserJet 3330
HP LASERJET 3200
Ju} 6 2005 8:05AM
Fax Call Report
i n v e n t
3ob Date Time Type
808 7/ 6/2005 8:04: 18AM Send
Identification
2143615573
Duration
1:33
Pages
3
Result
OK
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