<br />E52
<br />
<br />FLOODS OF 1965 IN THE UNITED STATES
<br />
<br />maximum flood of record are given in table 19; unfortunately, of the
<br />four sites, the 1935 flood peak is known only at North Platte. During
<br />the June 21-24 flood, the flood plain of the South Platte River was
<br />inundated to a width of 2 miles along some reaches, a condition caus-
<br />ing considerable damage to crop and pasture lands, Failure of a dike
<br />at Hershey resulted in the flooding of 12 homes and about one-third of
<br />the town. Farther downstream, below the confluence of the South
<br />Platte and the North Platte Rivers, the flooding diminished, but the
<br />peak discharge at Brady (table 19) was the largest and that at Cozad
<br />was the second largest since records began at those two gaging sta-
<br />tions in 1937, However, on the basis of earlier records at stations up-
<br />stream and downstream from these sit"", the 1935 flood is believed
<br />to have been greater than the June 1965 flood at both Brady and Cozad,
<br />Based on regional studies, the recurrence intervals of the 1935 and
<br />June 1965 flood discharges of the Sonth Platw River at North Platte
<br />are more than 50 years and 25 years, respectively. By contrast, the
<br />peak discharge of the 1935 flood on South Platte River at Julesl>urg,
<br />Colo. (period of record, 1902-64) was exceeded only by the flood of
<br />June 20, 1965,
<br />Generally heavy rains over southeastern Nebraska on June 25-30
<br />caused local flooding along many streams, l>ut rainfall was heaviest
<br />and flooding most extensive in the N emaha River basin, Of particular
<br />significance among causes of the flood was the heavy antecedent rain-
<br />fall observed at some Weather Bureau gages June 26-28 that set the
<br />stage for the high percentage and the great volume of runoff from
<br />the heavy rainfall of June 26-29 (twble 20). A farmer living near the
<br />Boy Scout camp south of Humboldt reported to the Falls City J ourual
<br />that 13,10 inches of rain fell,at his home-en June.25-3(}. This amount
<br />included 6 inches during the night of June 26-29 and 3112 inches during
<br />the night of June 29-30. The peak stage at the gaging station on
<br />Nemaha River at Falls City (St.. 10) occurred on June 29 (table 19).
<br />It was the highest in the period of record, which began in 1944, but
<br />the peak discharge was less than that in 1954. About 14,000 acres of
<br />farmland along the N emaha River between Salem and Preston was
<br />inundated, Much of this land was planted in wheat and was ready
<br />for harvesting. Several thousand acres along tributaries of the Nemah..
<br />River also were flooded. Many bridges and culverts were either de-
<br />stroyed or badly damaged, and a large amount of gravel surfacing was
<br />washed off flooded sections of county and State roads. Tiaffic was
<br />halted on U.S, Highway 73 south of F..lls City (near sta_ 10) for several
<br />hours at the height of the flood, and State Highway 8 between Du Bois
<br />and Salem was closed when approaches to two bridges were washed out
<br />on June 29. In the Pawnee City vicinity (about 10 miles northwest of
<br />
<br />I
<br />t
<br />
<br />I
<br />,
<br />
<br />SUMMARY OF FLOODS
<br />
<br />E53
<br />
<br />Du Bois), Turkey Creek flooded State Highway 65.south of'town
<br />and State Highway 4 at the underpass west of town. A small creek
<br />that runs through Pawnee City was reported to have reached the
<br />highest stage in the memory of local residents. A farm family living
<br />south of Humboldt was isolated when two bridges in the immediate
<br />vicinity washed out during the flood. About 1 mile southwest of
<br />Du Bois another farm family was stranded; floodwater inundated
<br />their home, farm buildings, machinery,- and automobile and drowned
<br />one horse and many of their chickens.
<br />
<br />TABLE 20.-Daily precipitation associated with the floods of June fJ9 in southeastern
<br />Nebraska .
<br />
<br />8it~ofobserva.tion
<br />
<br />Timaof
<br />observation
<br />(hours)
<br />
<br />Precipitation, in inches
<br />J_
<br />
<br />29
<br />
<br />30 2&-30
<br />
<br />26
<br />
<br />27
<br />
<br />28
<br />
<br />Dawson.___..___..________"__u_______________
<br />FallsCity____..._____u______________________
<br />Pawnee CitY._un________"-____uuu_u_u_
<br />Smiles southeast of Pawnee City_____________
<br />5 miles north of Table Roolc_um.u.__.mu
<br />Tecumseh~u_u_____ __._h........ _....__.___
<br />
<br />2400
<br />Sunset
<br />0700
<br />2400
<br />0700
<br />1900
<br />
<br />0.05 0.38
<br />1.08 .30
<br />.80 .94
<br />.91 mum
<br />.81 .72
<br />.63 .13
<br />
<br /><62
<br />1.10
<br />,84
<br />(')
<br />.47
<br />,18
<br />
<br />1.80 _h..._... 6.85
<br />3.87 0.73 7.08
<br />6.31 .71. 9.60
<br />9.16 .09 10.16
<br />3.15 .52 5.67
<br />2.35 .70 3.99
<br />
<br />1 Amountincluded inmeasurementfor June29j recorder not operating 2100-2400 hours; 5.66 inches recorded
<br />prlortQ2100hours.
<br />
<br />FLOODS OF JUNE-AUGUST IN UTAH
<br />
<br />By ELMER BUTLER
<br />
<br />Many floods occurred throughout Utah from early June to the
<br />, middle of August, In Utah,. springtime floods are usually-caused by
<br />snowmelt or rain on snow, and sununertime floods are generally caused
<br />by thunderstorms. Sununertime storms result from unstable moisture-
<br />laden airmasses that move in from the Gnlf of Mexico, often cover
<br />small areas, and cause precipitation of high intensity. The resulting
<br />peak discharges from small contributing areas may be very high.
<br />In many parts of Utah, rain gages are sparsely distributed, and if
<br />an area covered by a storm is small, the reported rainfall figures may
<br />not reflect the intensiy of a storm which produced a large flood.
<br />The most nowworthy floods in Utah from early June to the middle
<br />of Augnst are hereby described in chronological order. Fignre 24 shows
<br />the locations of peak discharge determination points. The sites at
<br />which peak discharges were determined for the several flood periods
<br />are liswd in downstream order in table 21.
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