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SECWCD
<br />June 16, 2005
<br />4
<br />RECORD OF PROCEEDING
<br />U.S. GEOLOGICAL SURVEY REPORT:
<br />Mr. Edelmann reported, this year streamflow in the upper Arkansas River Basin peaked,
<br />depending on locale, between May 23 and May 30, about one to two weeks earlier than normal.
<br />Non - regulated streamflows in the upper Arkansas River Basin indicated that snowmelt runoff
<br />was delayed and the duration of runoff was shorter than normal. Downstream from Twin Lakes,
<br />streamflow peaked on the Arkansas River, depending on locale, between about 2,100 and 2,600
<br />cfs. Downstream from Pueblo at Arkansas River near Avondale, the flow peaked on May 29 at
<br />about 3,200 cfs.
<br />Mr. Edelmann said 40 years ago this week, between June 16 -19, 1965, the near "perfect storm"
<br />occurred devastating much of the lower Arkansas River Basin. The following information
<br />adapted from "Floods of June 1965 in the Arkansas River Basin, Colorado, Kansas, and New
<br />Mexico ", USGS Water - Supply Paper 1850 -D by Snipes, and Others. In general, Colorado
<br />received fairly heavy rain on June 14, light rain on June 15, and very heavy rains on June 16 and
<br />In southern Colorado, the floods originated near Colorado Springs; south of the Arkansas
<br />River from Las Animas to the Colorado/Kansas stateline; and the Purgatoire River Basin. Jimmy
<br />Camp Creek, which enters Fountain Creek just upstream of Fountain, had a peak flow of 124,000
<br />cfs. Fortunately, this peak occurred a few hours before another peak on Fountain Creek at
<br />Security. Had the two peaks coincided, the effect downstream at Pueblo could have been
<br />disastrous. The peak flow on Fountain Creek near Fountain of at least 124,000 cfs attenuated to
<br />47,000 cfs at Pueblo, which still exceeded the peak flows of the 1921, 1935, and 1999 floods.
<br />The 1965 peak flow on Fountain Creek at Pueblo was almost 2.5 times the 1999 peak flow of
<br />18,900 cfs. The river stage was about 19 feet in 1965, whereas the river stage in 1999 was about
<br />10 feet.
<br />The highest peak flow determined on the Arkansas River above John Martin Reservoir was
<br />104,000 cfs downstream of Chico Creek resulting from coinciding flood crests from the
<br />Arkansas River near Avondale and 52,200 cfs from Chico Creek. Upstream of Chico Creek, the
<br />Black Squirrel Creek had a peak flow of 141,000 cfs.
<br />hi Trinidad, flooding began on June 16, 1965. On June 18, two peaks of about 60,000 cfs
<br />occurred on the Purgatoire River near Las Animas; the second peak had significantly attenuated
<br />from the peak flow of 105,000 cfs that occurred about 33 miles upstream from Las Animas.
<br />On June 17 the gates in John Martin Reservoir were closed and between June 17 -21, 1965 the
<br />contents in John Martin Reservoir increased 271,300 acre -feet; 87,000 acre -feet from the
<br />Arkansas River and 240,800 acre -feet from the Purgatoire River. Downstream from John Martin
<br />Reservoir, the sum of the peak flows from Caddoa, Mud, and Dry Creeks was almost 120,000
<br />cfs. Channel storage and differences in flood peak timing reduced these combined flows to
<br />73,800 cfs on the Arkansas River at Lamar. The peak flows on the tributaries between Lamar
<br />and Colorado/Kansas stateline was nearly 255,000 cfs resulting in flooding downstream through
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