Oakbend Add/FP-CS 930119 Future
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January 19, 1993
P.O. Box 478
Coppell, Texas 75019
214-462-0022
Mr. Derek E. Earle, P.E.
Centex Real Estate Corporation
1660 S. Stemmons Freeway
Suite 150
Lewisville, TX 75067
RE: Oakbend Addition Proposed Pedestrian Bridge
Dear Derek:
I have reviewed your request for a proposed pedestrian bridge to access Lot 52, Block A, of the
Oakbend Addition. The HEC II study that was submitted appears to have some problems with
the cross section information in regard to the elevation of property on the west side of the creek
that bisects Lot 52. I am not sure if the cross sections are actually field surveyed or taken off
of old contour maps. I have referenced our new topography maps flown in February of 1992
to ascertain some elevation information. Based on those 1992 topography maps and the water
surface through this area from the Albert Halff Stormwater Study, it is my opinion that the top
width of the water at the location of the proposed pedestrian bridge will be substantially wider
than shown on your flood study. The Albert Halff Stormwater Study shows a 100-year water
surface of approximately 498.2 at the location of the proposed pedestrian bridge.
Based on: the 100-year water surface of 498.2; the fact that the low cord elevation of the
pedestrian bridge should be one foot above the 100-year water surface (499.2); the February,
1992, aerial map information; and the Albert Halff Flood Study, it is my opinion that to
construct a pedestrian bridge in this area would take a clear span of approximately 125 feet and
a low cord elevation of 499.2.
If it is your intention to fill in the west side of the creek on Lot 52, then you will need to submit
a detailed flood study in accordance with our Flood Plain Policy. That flood study will be
reviewed by our outside consultant at a cost of $1,000 and then forwarded to the Federal
Emergency Management Agency (FEMA) for a Conditional Letter of Map Revision. After the
Conditional Letter of Map Revision is obtained, then (based on the area of the reclamation),
consideration could be given to a pedestrian bridge of a smaller clear span.
Your letter of November 12, 1992, referenced the fact that the pedestrian bridge will be
dedicated to the homeowner's association. Please be advised that the City of Coppell will not
issue approvals or permits for the pedestrian bridge until such time as the homeowner's
association agreement has been submitted to the City for review and approval and has been filed
with the County. It should specifically contain wording to the effect that the pedestrian bridge
is part of the homeowner's maintenance responsibilities. If you should have any questions
concerning this issue, please feel free to contact me at your convenience.
Sincerely,
Kenneth M. Griffin, P.E.
City Engineer
cc: Alan Ratliff, City Manager
c/~ary Sieb, Director Planning & Community Service
KMG/pn