FLOOD10576

• County: Gilpin
• Community: Black Hawk
• Stream Name: North Clear Creek
• Title: LOMR - Affected Panel 0001 B - Case No. 01-08-251P
• Date: 6/20/2002
• Prepared For: Black Hawk
• Prepared By: FEMA
• Floodplain - Doc Type: Historic FEMA Regulatory Floodplain Information

CHANGES ARE MADE IN DETERMINATIONS OF BASE FLOOD ELEVATIONS FOR THE CITY
OF BLACK HAWK, GILPIN COUNTY, COLORADO UNDER THE NATIONAL FLOOD
INSURANCE PROGRAM

On October 16, 1984, the Federal Emergency Management Agency identified Special Flood Hazard
Areas (SFHAs) in the City of Black Hawk, Gilpin County, Colorado, through issuance of a Flood
Insurance Rate Map (FIRM). The Federal Insurance and Mitigation Administration has determined that
modification of the elevations of the flood having a I-percent chance of being equaled or exceeded in any
given year (base flood) for certain locations in this community is appropriate. The modified Base Flood
Elevations (BFEs) revise the FIRM for the community.

The changes are being made pursuant to Section 206 of the Flood Disaster Protection Act of 1973 (Public
Law 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, Public Law 90-448), 42 U.S.C.
4001-4128, and 44 CFR Part 65.

A hydraulic analysis was performed to incorporate the effects along North Clear Creek of construction of
the Riviera Hotel and Casino project; removal of the Main Street bridge; construction of the new Mill
Street Bridge approximately 75 feet upstream of the former Main Street bridge; updated topographic
information; and channelization from approximately 800 feet downstream to approximately 50 feet
upstream of the former Main Street bridge, as referenced on the effective FIRM. This has resulted in
increases and decreases in SFHA width and increased and decreased BFEs for North Clear Creek. The
aforementioned channelized portion of North Clear Creek contains the base flood. The table below
indicates existing and modified BFEs for selected locations along the affected lengths of the flooding
source(s) cited above.

Location

Existing BFE
(feet) *

Modified BFE
(feet) *

Approximately 800 feet downstream of
former Main Street bridge
Approximately 900 feet downstream of
former Main Street bridge
Approximately 530 feet upstream of
former Main Street bridge

7,942

7,940

7,936

7,937

7,975

7,976

*National Geodetic Vertical Datum, rounded to nearest whole foot

Under the above-mentioned Acts of 1968 and 1973, the Federal Insurance and Mitigation Administration
must develop criteria for floodplain management. To participate in the National Flood Insurance Program
(NFIP), the community must use the modified BFEs to administer the floodplain management measures
of the NFIP. These modified BFEs will also be used to calculate the appropriate flood insurance premium
rates for new buildings and their contents and for the second layer of insurance on existing buildings and
contents.

Upon the second publication of notice of these changes in this newspaper, any person has 90 days in
which he or she can request, through the Chief Executive Officer of the community, that the Federal
Insurance and Mitigation Administration reconsider the determination. Any request for reconsideration
must be based on knowledge of changed conditions or new scientific or technical data. All interested
parties are on notice that until the 90-day period elapses, the Federal Insurance and Mitigation
Administration's determination to modify the BFEs may itself be changed.