Parks Coppell FS-CS 860523 Federal Emergency Management Agency
~:~ Washington, D.C. 20472
CERTIFIED MAIL ~AY Z3 ~ IA-RA-RS (102a)
RETURN RECEIPT REQUESTED
Community: City of Coppell,
The Honorable Lou Duggan Dallas and Denton
Mayor of the City of Coppell Counties, Texas
P.O. Box 478 Effective Date of
Coppell, Texas 75019 this Revision: May 23, 1986
Community Number: 480170
Dear Mayor Duggan: Suffix Code: C
This is in reference to a letter, dated May 20, 1985, submitted by Mr. H.
Wayne Ginn, P.E., former Coppell City Engineer, and subsequent submissions of
technical data from Wier & Associates, Inc., forwarded to us by our Region VI
office. In his letter, Mr. Ginn requested that the Federal Emergency Manage-
ment Agency (FEMA) review technical data prepared by Wier & Associates, Inc.,
describing a fill and channel modification project along Cottonwood Branch in
the vicinity of Winding Hollow Road, and issue a Letter of Belief for the
project.
FEMA's response to a community request for review and acceptance of a proposed
project to be built within a Special Flood Hazard Area (SFHA) is to issue a
Letter of Belief, also known as a conditional Letter of Map Revision (LOMR).
The purpose of a conditional LOMR is to inform the community that FEMA will
revise their effective Flood Insurance Study (FIS), Flood Insurance Rate Map
(FIRM), and Flood Boundary and Floodway Map (FBFM), contingent upon our
receipt of community endorsement and upon satisfactory completion of the
proposed project, with respect to all applicable National Flood Insurance
Program regulations. Because this request is based on a completed fill and
channel modification project, which will change the SFHA along Cottonwood
Branch, a LOMR will be processed instead of a conditional LOMR. A LOMR is
needed to revise floodplain delineations based on a change to the hydrologic
and hydraulic parameters utilized in the effective FIS, FIRM, and FBFM for a
community.
We have reviewed the technical data prepared by Wier & Associates, Inc., which
consisted of final HEC-2 modeling dated February 28, 1986, and "as-built"
plans dated January 1986. Based on this review, the SFHA for the portion of
Cottonwood Branch from Sandy Lake Road to a point approximately 3,850 feet
downstream, has been reduced as shown on the enclosed annotated copies of the
FIRM and FBFM. The zone designation for the revised area has been changed
from Zone A2 to Zone A3. The table below indicates the width of the revised
SFHA at selected locations within the referenced portion of Cottonwood Branch.
SFHA (Zone A3) Width (in feet)
Approximate Location Existing Modified
650 feet downstream of Sandy 450 375
Lake Road
1,600 feet downstream of Sandy 890 650
Lake Road
3,300 feet downstream of Sandy 1,010 600
Lake Road
2
This LOMR amends the currently effective FIRM panel 480170 0005C and FBFM
panel 480170 0005, both dated February 15, 1984.
This LOMR is based in part on a channel modification. It should be noted,
therefore, that National Flood Insurance Program regulation 44 CFR 60.3 (b)(7)
requires that communities "assure that the flood carrying capacity within the
altered or relocated portion of any watercourse is maintained." This pro-
vision is incorporated into your community's existing floodplain management
regulations. Consequently, your community is responsible for ensuring ap-
propriate maintenance of channel modifications.
Due to present funding constraints, FEMA must limit the number of physical map
revisions processed. Consequently, we will not publish the FIRM and FBFM for
the City of Coppell to reflect these modifications at this time. However,
should your community's FIS warrant physical map revision in the future, the
changes described in this LOMR will be incorporated at that time.
These modifications have been made pursuant to Section 206 of the Flood
Disaster Protection Act of 1973 (P.L. 93-234) and are in accordance with the
National Flood Insurance Act of 1968, as amended (Title XIII of the Housing
and Urban Development Act of 1968, P.L. 90-448) 42 U.S.C. 4001-4128, and 44
CFR Part 65. As required by this legislation, a community must adopt and
enforce floodplain management regulations in order to ensure continued eligi-
bility to participate in the National Flood Insurance Program. Therefore, the
City of Coppell must enforce these regulations using, at a minimum, the
elevations and zone designations in the SFHAs as shown on your community's
FIRM, including the modifications made by this LOMR.
These modifications are effective as of the date of this letter. However, a
review of this detgrmination and any requests for changes should be made
within 30 days. Any requests for reconsideration must be based on scientific
or technical data.
Since this revision will not be printed and distributed to users such as
insurance agents and lenders, the community will ser~e as a repository for the
new data. We encourage you to disseminate widely throughout the community the
information reflected by this LOMR in orde~that interested persons may offer
new information or comments.
The community number and suffix code listed above will be used for all flood
insurance policies and renewals issued for your community.
A Consultation Coordination Officer (CCO) has been designated to assist you
with any problems you may have concerning these modifications. The CCO will
be the primary FEMA contact for your community. Your CCO is:
Mr. R. Dell Greer, Chief
FEMA, Natural & Technological
Hazards Division
Federal Regional Center
800 North Loop 288
Denton, Texas 76201
(817) 387-5811
~y questions may be direct~ to your CCO.
Sincerely,
~h~ L. Matticks
A't~g Chief, ~sk Studies Division
Federal Insurance Administration
cc: ~. ~ Powell, P.E., Ci~ Engineer
Mr. David McCarver, P.E., Wier & Associates, Inc.
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