FLOOD04875

• County: Weld
• Community: Eaton
• Basin: South Platte
• Title: FIS - Eaton
• Date: 9/22/1999
• Prepared For: Eaton
• Prepared By: FEMA
• Floodplain - Doc Type: Current FEMA Regulatory Floodplain Information

exist on this floodplain.
agriculturally oriented.

Those that do exist are primarily

2.3 Principal Flood Prohlems

Flooding along the South Platte River normally occurs between May
and August, with the most frequent flooding occurring in June.
Floods can result from intense local rainfall, as in 1965, or
general rainstorms lasting several days, as in 1969 and 1973. Both
types of flooding may be augmented by snowmelts. Floods on the
South Platte River have occurred as follows: May 1876; late May
and early June 1914; June 1921; from August 30 to September 4,
1938; April and May 1942; May and June 1949; May 1951; June 1965;
May 1969; and, May 1973. The floods of June 1921 and May 1973 are
estimated to have frequencies of approximately 100 years.

Damaging floods occurred in the study area of the Cache La Poudre
River in 1876, 1884, 1904, 1917, 1923, 1947, 1949, 1951, 1964, and
19,65. The largest flood in recorded history was in 1917 with an
estimated discharge of 13,000 cubic feet per second. <cfs) in the
are of the City of Greeley (Reference 4).

Historic records of flooding on Eaton Draw are not very concise. A
major flood is known to have occurred on May I, 1977, when flood
depths in the vicinity of the Town of Eaton approximated those of
the 100-year flood. Other floods occurred on various parts of
Eaton Draw in 1935, 1951, 1954, 1961, 1965, 1972, and 1974.

The most significant floods of recent times along the Tri-Area
Drainageway occurred in 1957, 1961, and 1975. On June 3, 1961, 2
to 4 inches of rain fell in a 2-hour period in the drainage basin.
The Tri-Area Drainageway flows swelled, flooding sections of the
Towns of Firestone, Frederick, and Dacano. This was similar to the
flood of 1957, which caused structural damage to the same area. In
1965, heavy rains and hail caused extensive flooding, and housing
damages were reported in the thousands of dollars.

Local residents reported shallow flooding in the U.S. Highway 34
Levee Overflow Channel during May 1973, with no resulting damage.

No flood history is available for Sheep Draw or Ashcroft Draw, as
these areas have not been extensively developed.

Photographs of the 1977 flood on Eaton Draw and the 1969 flood on
the South Platte River are provided in Figures 2 through 4.

Flooding along the Big Thompson River generally occurs between May
and July. However, annual peak discharges have been experienced
from March through September. Floods can have considerably
different characteristics depending upon the location within the
basin and generally have a duration of about 1 day. In July 1976,
heavy rainfall, amounting to as much as 12 inches in 4 hours, fell
on the evening of July 31 in the upper Big Thompson River basin, in

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