FLOOD05134

• County: Jefferson
• Community: Lakewood
• Stream Name: South Lakewood Gulch
• Basin: South Platte
• Title: Flood Hazard Area Delineation
• Date: 7/1/1977
• Prepared For: Lakewood
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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FLOODPLAIN MANAGEMENT

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Reduced flood damages.
Reduced urban disruption.
Reduced street construction costs.

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Floodplain management includes all measures for planning and action which
are needed to determine, implement, revise, and update comprehensive plans
for the wise use of floodplain lands and their related water resources.
This includes both preventive and corrective actions, the latter encom-
passing flood control works such as detention basins and selected channel-
ization which will not be discussed in this report.

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Reduced street highway maintenance costs.
Water oriented recreation opportunities.

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Floodplain management seeks to mitigate the effects of a flood event in
lieu of altering the flood event. Because of its relatively recent accep-
tance as a viable alternative, it is separately discussed.

. Multipurpose open space.

. Less problems with high water table.

. Trails for hiking, biking, and horseback riding.

. Preservation of natural floodplain storage.

. Potentially reduced sewer pipe infiltration and inflow.

. Improved stream water quality.

. Better quality of nonpoint discharges of urban runoff

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Land use management is the keystone of floodplain management. In its
broadest terms it involves both land use and runoff controls. It involves
a set of actions at the local government level which can be relied upon to
guide the wise use of public and private flood-prone land. These actions
include acquisitions, land valuations, investments, and the provision of
information.

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Early Examples

CORRECTIVE ACTIONS

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Floodplain management is not new. For instance, Empress Maria-Theresa
(1740-1780) of the Austro-Hungarian Empire decreed that a wide floodplain
be left undeveloped adjacent to Vienna for the Danube River. Current public
works engineers for Vienna are grateful for her foresight.

To address the backlog of flood problems in South Lakewood Gulch, corrective
actions must be taken. These actions include the general headings of flood
proofing and land use adjustments along with some channelization and bridge
and culvert improvements. In a comprehensive program, preventive actions
need to be integrated with corrective actions. This allows a dynamic inter-
action between elements to achieve the most cost-effective design.

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U.S. Development

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PLAN COMPONENTS

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Modern articulation of floodplain management in the United States of America
dates to 1945 when Dr. Gi Ibert White prepared his paper entitled "Human
Adjustment to Floods: A Geographical Approach to the Flood Problem in the
United States." Progress was slow until 1966 when the Task Force on Federal
Flood Control Pol icy chaired by Dr. White reported to the President of the
United States in a document entitled "A Unified National Program for Manag-
ing Flood Losses," after which President Lyndon Johnson issued Executive
Order 11296 dealing with Federal policy on floodplain development.

A floodplain management plan must call upon the use of many components to
be effective and practical.

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The components of this recommended program fall under the broad categories
of structural improvements, land use management, early warning, land runoff
control, flood proofing, insurance, and relief and rehabilitation. The
structural improvements are described in a separate report for South Lake-
wood Gulch with the remainder of the components described below.

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The 1974 Water Resource Development Act, in Section 73, puts nonstructural
alternatives on a par with structural approaches and requires all U.S.
Federal agencies to consider nonstructural alternatives in their planning
process.

Control of Floodplain Land Uses

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PREVENTIVE ACTIONS

Floodplain land uses may be affected by either floodplain controls or land
acquisition. By controlling the amount and type of economic and social
growth in the floodplain, flood losses are reduced and net benefits from
suitable floodplain use increases.

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Throughout much of Lakewood, preventive measures to achieve flood damage
mitigation can be taken. When preventive measures are implemented, a
range of benefits can be real ized. These include:

Although this approach may require long periods to exercise its full effect,
the incentives are strong. They include reduction in the exposure to risk,
reduction in publ ic costs for relief and rehabil itation, and decreased de-
pendence upon protective works.

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