BOARD01965

• Board Meeting Date: 3/22/2005
• Description: Flood Section - Presentation of the CWCB's Draft Rules and Regulations for Regulatory Floodplains in Colorado
• Board Meetings - Doc Type: Memo

Term
500-year floodplain

"Flood" or
"Flooding"

Flood Insurance Rate
Map (FIRM)

Flood Contour

Flood Mitigation
Project

Floodplain

Floodplain
Management

Floodplain
Management
Regulations

"

Definition
An area that has a 0.2 percent chance of flooding in any given year. This
standard is not used for determining the need for flood insurance, but the
Board's operating principle # 8 (Critical Faciliiies) recommends
consideration of 500-year floodplain mapping for fire departments,
hospitals, police stations, electrical power stations, etc.

A general and temporary conditional or partial or complete inundation of
normally dry land areas from:
I. The overflow of water from channels and reservoir spillways;
2. The unusual and rapid accumulation or runoff of surface waters
from any source; or
3. Mudslides (e.g., mudflows) excess surface water that is combined
with mud and other debris that are sufficiently fluid so as to flow
on and over the surface of normally dry land areas, as when earth is
carried by a current of water and deposited along the path of the
current.

A FIRM is the official map of a community on which FEMA has
delineated both the special hazard areas and the risk premium zones
applicable to the community.

A line shown on a map joining points of equal elevation on the surface of
floodwater that is perpendicular to the direction of flow.

A project within or adjacent to a flooding source that is specifically
intended to reduce or eliminate the negative impacts caused by excessive
floodwaters through improvement of drainage, flood control, flood
conveyance or flood protection.

The area of land that could be inundated as a result of a flood, including
the area of land over which floodwater would flow from the spillway of a
reservOIr.

The operation of an overall program of corrective and preventive measures
for reducing flood damage, including, but not limited to, zoning or land-
use regulations, flood control works, and emergency preparedness plans.

Zoning ordinances, subdivision regulations, buiJding codes, health
regulations, land-use permits, special purpose ordinances (floodplain
ordinance, grading ordinance, or erosion control ordinance) and other
applications of police powers. The term describes state/local regulations
that provide standards for flood damage preservation and reduction.

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