FLOOD01611

• County: Boulder
• Community: Boulder County
• Stream Name: Upper Lefthand Creek-Foothills Hwy to Peak to Peak
• Title: Flood Information Report
• Date: 8/1/1983
• Prepared For: Boulder County
• Prepared By: UDFCD
• Floodplain - Doc Type: Floodplain Report/Masterplan

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Flooded Areas

a known point, the high water elevations can be surveyed on the ground to
alleviate any discrepancies on the base map.
Survey control markers exist in the field in the vicinity of
Lefthand Creek and its associated floodplain area to assist in performing
this task. A summary of these control markers and their locations is
given in Table 7.

The 100-year frequency flood has been selected by the State of

Colorado as the flood event to be used for floodplain delineation and

regulation. The Flooded Area Plates show both the boundary of the
100-year floodplain and the SOD-year floodplain. Since the base map for
the Flooded Areas Plates is a contour map, the outlines of the other
flood events can be readily plotted using the information in Table 6.
The area delineated on the Flooded Areas plates as the 100-year
floodplain meets the requirements of H.B. 1041 as an area of state
interest. Also, upon official approval of this report by the Colorado
Water Conservation Board, the area outlined by the 100-year flood

Flood Insurance

Flood Elevations

The National Flood Insurance Program is a Federal program that

enables property owners to buy flood insurance at a reasonable subsidized

cost. In return, communities are required to carry out floodplain man-

agement measures to protect lives and new construction from future

flooding.

Flood insurance through the National Flood Insurance Program is

available to all residents of Boulder County under the regular phase of

the program. 80ulder County entered the regular program February 1,

1979. A Flood Insurance summary is shown in Table 8.

Additional information on the Flood Insurance Program is available

from any local insurance agent or broker and the:

Federal Emergency Management Agency
Division of Insurance and Mitigation
Denver Federal Center, Building 710
Lakewood, Colorado 80225
Telephone: [phone]

boundary will be designated a floodplain area and may be regulated
accordingly by the local officials.

Flood crest elevations for the 10-, 50-, 100-, and SOD-year floods
may be found in three separate locations in this report. The flood
frequency-elevation and discharge data table (Table 6) lists these eleva-
tions at selected reference points. The Flooded Area Plates 3 through 28
give the plan view of the flooded area on a contour base map and the high
water elevations for the 100-year flood can be interpolated from this.
The Flood Profile Plates 29 through 38 show the stream bed elevation and
the high water elevations for all four frequency floods.
The flood profiles may be used in areas where controversy arises
over the 100-year flood boundary on the Flooded Area Plates. Since the
Flood Profile Plates give the elevations and distance or stationing from

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