|
<br />.
<br />
<br />STUDY AREA DESCRIPTION
<br />
<br />Communitv Description
<br />Morgan County is located in eastern Colorado within the South Platte River valley. Fort Morgan is
<br />the county seat of Morgan County, and is located approximately 70 air miles northeast of Denver,
<br />and approximately 50 air miles southeast of Greeley. Highway 76 is the major east-west highway
<br />that serves the county, The South Platte River bisects the county and generally flows through it
<br />from west to east. Elevations in the county range from about 4,000 feet to over 5,000 feet. The
<br />area studied for the PIS is the unincorporated areas of Morgan County as of September 29, 1989,
<br />
<br />Watershed Description
<br />The South Platte River flows through Morgan County from west to east and has a generally well
<br />defined main channel and floodplain, The channel is typically braided, and lies within a broad,
<br />shallow valley ranging in width from about 0,25 miles to 4 miles. The average streambed slope
<br />through Morgan County is about 6 to 7 feet per mile, The drainage area of the South Platte River at
<br />Fort Morgan is 14,810 square miles, Most ofthe major tributaries in Morgan County are right-bank
<br />tributaries that flow into the South Platte River from the plains area to the south. Examples of these
<br />large tributaries include Kiowa Creek, Bijou Creek, Beaver Creek, and Badger Creek. The
<br />headwaters of the South Platte River originate at the Continental Divide with elevations in excess
<br />of 14,000 feet. The South Platte River, along with the tributaries listed above, are just some of the
<br />major flooding sources within the unincorporated areas of the county.
<br />
<br />.
<br />
<br />Floodinl! Problems and Floodinl! Historv
<br />Flooding on the South Platte River normally occurs during the spring and summer months from
<br />May through September as a result of flooding from thunderstorms or general rainstorms which can
<br />be enhanced by rapid snowmelt runoff from the upper watershed areas, Flooding on the tributary
<br />streams in Morgan County are almost always a result of intense thunderstorms or heavy general
<br />rainstorms during the late spring and summer months,
<br />
<br />There have been numerous high water events on the South Platte River at Morgan County, The
<br />most recent high water occurred during 1995, On June 1, 1995 a significant peak flow of 21,000
<br />cfs was recorded on the South Platte River near Kersey, which is in Weld County upstream of
<br />Morgan County, Significant high water on the South Platte in Morgan County also occurred in
<br />1864,1894, 1921, 1935, 1949, 1951, 1957, 1965, 1969, 1973, 1980, and 1983, This is by no means
<br />a complete accounting of the flood years in this area,
<br />
<br />A record flow of 123,000 cfs was recorded on June 18, 1965 at the Balzac gage located near the
<br />Morgan-Washington County line, Floodwaters originating from Bijou Creek traveled down the
<br />South Platte and reached Fort Morgan on May 31, 1935 with a reported peak flow of 84,000 cfs, A
<br />streamflow gaging station on the South Platte at Fort Morgan was operated from 1944 to 1958,
<br />Notable peak flows recorded at that gage include 33,800 cfs on August 3, 195 I and 20,900 cfs on
<br />May 16,1957,
<br />
<br />.
<br />
<br />2
<br />
|