FLOOD01779

• County: Jefferson
• Community: Westminster
• Stream Name: City Park Channel
• Title: LOMR - Affected Panel 08059C 0091 E, 08059C 0093 E - Case No. 03-08-0023P
• Date: 4/14/2004
• Prepared For: Westminster
• Prepared By: FEMA
• Floodplain - Doc Type: Historic FEMA Regulatory Floodplain Information

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i'1H~C~~VIED

DEe 2 ~ 2003
Federal Emergency Management Agency
Washington, D.C. 20472 4)ctollldoWaterConservatlon Board

DEe 1 8 2003

CERTIFIED MAIL
RETURN RECEIPT REQUESTED

IN REPLY REFER TO:
Case No.: 03-08-00231'

The Honorable Ed Moss
Mayor, City of Westminster
4800 West 92nd Avenue
Westminster, CO 80031

Community: City of Westminster, CO
Community No.: 080008
Panels Affected: 08059C0091 E and 0093 E
Effective Date of
This Revision:

APR 1 4 2004

102-I-A-C

Dear Mayor Moss:

This responds to a request that the Department of Homeland Security's Federal Emergency Management
Agency (FEMA) revise the effective Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS)
report for Jefferson County, Colorado and Incorporated Areas (the effective FIRM and FIS report for your
community), in accordance with Part 65 of the National Flood Insurance Program (NFIP) regulations. In a
letter dated October 9, 2002, Mr. David W. Loseman, P.E., L.S., Senior Projects Engineer, Floodplain
Manager, Department of Community Development, City of Westminster, requested that FEMA revise the
FIRM and FIS report to show the effects of channel modifications associated with the Sheridan Crossing
development;_drainage.improvements.along-Gity-l'ark-Ghannel-from.approximately-2,OOO-feet-downstream
to approximately 450 feet upstream of Sheridan Boulevard; and construction of the Cozy Comer
drainageway improvements. This request follows up on a Conditional Letter of Map Revision issued on
January 27, 1997.

The drainage improvements along City Park ChalU1el included: widening of the chalU1el; construction of a
low-flow chalU1el; construction of three new road crossings located approximately 490 feet downstream,
930 feet downstream, and 1,870 feet downstream of Sheridan Boulevard; modifications to the existing
culvert crossing at Sheridan Boulevard; and construction of the Clover Creek diversion flow structure and
diversion chalU1el to Cozy Creek Channel, located approximately 730 feet downstream of Sheridan
Boulevard. The Cozy Comer drainageway improvements included the above-mentioned Clover Creek
diversion structure a 8-foot by 5-foot reinforced-concrete box culvert (RCB), which extends from City
Park Channel to approximately 830 feet south, and the Clover Creek diversion channel, which extends
approximately 1,550 feet south from the RCB to the Clover Creek detention pond. Outflows from the
Clover Creek detention pond will flow into Cozy Creek Channel approximately 2,900 feet upstream of the
confluence with Big Dry Creek. The confluence of Cozy Creek Channel with Big Dry Creek is located
approximately 5,200 feet downstream of 112th Avenue.

The Special Flood Hazard Area (SFHA), the area that would be inundated by the flood having a I-percent
chance of being equaled or exceeded in any given year (base flood), shown on the effective FIRM along
City Park ChalU1el is designated Zone AE, with Base Flood Elevations (BFEs) determined. Areas on the
effective FIRM that are affected by Clover Creek Channel and Cozy Corner Channel are designated
Zone X (unshaded), areas outside the floodplain of the flood having a 0.2-percent chance of being equaled
or exceeded in any given year.