FLOOD05827

• County: Boulder
• Community: Boulder
• Stream Name: Boulder Creek
• Basin: South Platte
• Title: Boulder Creek Phase B
• Date: 12/1/1979
• Prepared For: Boulder
• Prepared By: UDFCD
• Floodplain - Doc Type: Floodplain Report/Masterplan

This master plan was based on the United States Army Corps of Engineers'

hydrology, Plan I I excavated floodway concept between 6th and l7th

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In June of 1970, a Corps of Engineers Committee on Environmental Planning,

Boulder Subcommittee (Boulder Creek Subcommittee) was formed to advise

the Corps of Engineers on local and environmental issues.

The citizens of Boulder are interested in preventing flood damages. The

City has flood plain regulations to prevent creation of new hazards.

The City of Boulder, in cooperation with Boulder County and the Urban
Drainage and Flood Control District (UDFCO), has developed an emergency
evacuation program to reduce the hazard for loss of life.

In May of 1977, the Boulder City Council adopted l2,000 c.f.s. as the
design discharge and authorized an "early action" program to implement

an excavated floodway improvement concept generally known as Plan I I,

between 6th and Broadway, beginning at 6th Street, as developed in the

1977 COE Report.

The City of Boulder, in cooperation with the UDFCD and other interested

parties, have undertaken this detailed study to develop plans for the

area upstream from l7th Street and to investigate replacement of bridges

and other restrictions for the area downstream from l7th Street. At

the conclusion of these planning activities, the City expects to be in

a position to decide whether they wish to seek Federal assistance to

implement this project.

In June of 1977, the Boulder City Council authorized funds to provide
improved crossings at 6th and 9th Streets designed to convey the esti-
mated 100-year discharge of l2,000 c.f.s. In November of 1977, the
Boulder City Council formally agreed to improve the crossings at 6th and

9th Streets. Several of the Boulder Creek Subcommittee members became

concerned that the proposed improved crossings would mandate Plan II to

the exclusion of Plan II I, a master plan concept based on floodproofing

and relocation of existing facilities within the 100-year flood plain.

Further investigation revealed that the proposed improved crossings at

6th and 9th Streets would accommodate either Plan liar Plan III..

B. BOULDER CREEK MASTER PLAN DEVELOPMENT & SUMMARY

In January of 1978, the City of Boulder, Boulder County, and the Urban

Drainage and Flood Control District entered into agreement with the URS

Company to analyze the various flood control measures proposed by the

COE based on a flood discharge of 12,000 c.f.s.

In September of 1978, the City of Boulder started construction of a

flood protection berm from the northeast corner of Canyon Boulevard

extending 900 feet to the east to protect a low income housing project

(Canyon Painte) sponsored by Housing and Urban Development (H.U.D.)
against floodwaters associated with a 100-year discharge of 12,000
c.f.s. on Boulder Creek. With the exception of this flood protection
berm and the improved crossings at 6th and 9th Streets none of the

improvements proposed in this Plan have been implemented to date.

The objective of this master planning effort was to develop a hydrauli-
cally sound and aesthetically pleasing master plan based on the Corps of

Engineers' plan concepts that would strike a balance between improve-

ments required to convey the lOO-year discharge and preservation of the

existing environment.

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