FLOOD09948

• County: Hinsdale
• Community: Lake City
• Stream Name: Gunnison River, Henson Creek
• Basin: Gunnison
• Title: Floodplain Information Report
• Date: 10/1/1985
• Prepared For: Lake City, Hinsdale County
• Prepared By: Westwater Engineering
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

Flcoaplaln An area i.1dndadJacen,toa stream, wnicnarea is
subject to flooding as the result of the occurrence
of a tOO-year flood and which area thus is so adverse
to past, current, or foreseeable construction or iand
use as to constitute a significant hazard to public
health and safety or to property.

FlOOd Profile A graph showing the relationship of water surface
elevation to location, the latter generally expressed
as distance above mouth for a stream of water flowing
inanopenchannel. It is generally drawn to shOw
surface elevation for the crest of a speCific flood,
but may be prepared for conditions at a given time or
stage.

Flood Stage The stage or elevation at which overflow of the natural
banks of a stream or body of water begins in the reach
or area in which the elevation is measured.

Meander

Peak Discnarge

Precipitation

Probability

Reach

Floodway The Channel of a stream and tne portions of the
adjoining floodplain required to pass the discnarge
of the 10D.year flood with an insignificant increase
in flood levels. As used In the National Flood Insurance
Program, floodways must be large enougn to pass the
100.yeardlschargewlthoutcausingti1eiloodt:ievation
to increase more than a specified amount (usually
one foot).

Recurrence
Interval

Reference Point

Rightllank

Runoff

Left Bank The bank on the left side of a river, stream or water
course as the observer looks downstream.

L01-PearsonType
II OlstrlDutlon A statistical distribution used in flood frequency
analysis, which is described by three parameters; mean,
standard deviation. and coefficient of skewness of the
logarithms of tne sample observations.

Stream

Watershed

"'
'"

The w:nding of a stream cnannel.

The lar~est value of s~reamflo~ a~tai~ed by a flood,
usually reported In units of cubic feet cer second.

Is the discharge of water, in liquid cr solid state,
out of the atmosphere, generally upon a land or water
surface. Precipitation includes rainfall,snow, hail,
and sleet, and is therefore a more genera! term than
rainfall.

The annual chance of occurrence of specific hydrologic
events, such as rainfall over a specified area or peak
discharge at a specified location expressed in percent,
e_g. 5% representing one chance in 20 of the event
occurring in any year or an average recurrence of once
in twenty years.

A segment of the river defined between t~o specified points.

The average interval of time, in years, within Which a
given flood will be exceeded once.
A numbered point identifying a specific location for
correlating the data Shown in various forms throughout
tnereport.

The bank on the right side of a river, stream or water
course, looking downstream.

The quantity of rainfall which flows over the surface
to enter the stream as discharge volume. The difference
in quantity between rainfall and runoff represents losses
to infiltration and interception.

Any natural channel or depression through whicn water
flows either continuously, intermittently or periodically,
IncludIng any artificial modification of the natural
channel or depression.

The drainage area situated above a specified po:nt or.
a strea!ll!ncludingthe area drainel.iby tributary strea.':lS
which enter the main stream above this point.

3'