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<br />, 3-03. The peak discharge of the H~erfano River near Underclifte,
<br />Colorado, was 15,000 cubic feet per second and this peak would have~
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<br />been gl'eater except that Cucharas Dam stored about 15,000 acre feet,
<br />of the floodwaters. The peak discharge oftha, Apishapa'River was ,
<br />17,000 cubic feet per second and that of Timpas Creek was 7,500cub~o
<br />feet per second. '
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<br />3-04. Major urban flooding occurred at North 'La Junta, an uni~-
<br />corp orated residential section on the north bank of the Arkansas Riter
<br />directly across from the City of La Junta. It, is estimated that th$
<br />peak flow at La Junta was in 'excess of 45,000 cubic, feet per second,
<br />Peak discharge of the Arkansas River at Las Animas was 45,000 cubic I
<br />feet per second, and no serious flooding ocourred in the town of :
<br />Las Animas.
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<br />3-05. The center of heaviest precipitation was in the vicinity
<br />of Raton Pass, so Raton Creek and Long Canyon had the highest peaks~
<br />of any of the Purgatoire River tributaries. Raton Creek peaked at :
<br />10,400 cubic feet per second and Long Canyon at 11,400. Major floo4-
<br />ing on the Purgatoire began in th~ vicinity of Valdez,Colorado, and
<br />the stage at Trinidad reached 14.3 feet, the maximUm of record. The
<br />flow of 30,000 cubic feet per second (measured by indirect methods) ~
<br />at this stage indicates that a revision of previ.ov,~lv rublished 1'lo'1s
<br />for the 1942 and 1904 floods may be requireao ;~ntributions ~
<br />from other tributaries increased the flow to 78,000 cubic feet per I
<br />second at Ninemile Dam near Higbee, Colorado, which is the greatest~
<br />of record. Peak flow of the Purgatoire near Las Animas was 70,000 :
<br />cubic feet per second. Much of the precipitation in the Upper Pur-i
<br />gatoire Basin and other mountain areas was in thefonn of snow whi,clj.
<br />did not melt immediately, so the flood was of longer duration than :
<br />any previous flood at Trinidad. Peak flows for all points whel"e :
<br />determina tions have been made are shown on pIa te 6 and a summary of:
<br />peak stages and discharges, along with times of occurrenoe, is
<br />presented in table 1. Hydrographs at selected stations above John
<br />Martin Dam are shown on plates 7, 8 and 9. Comparison of the peak
<br />flows per square mile to the envelope curve of maximum experienced
<br />peak discharge in the Albuquerque District is shown on plate 10,
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<br />3-06. Flooding prevented below John Martin Dam. The peak in- I
<br />flow to John Martin Reservoir was about 88,000 c1Jbic feet per seconq
<br />at 7:00 a.m. on May 20, 1955, Had this flow continued downstream '
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<br />unimpeded. it would have caused disastrous flooding. The gates of ,
<br />,John Martin Dam were closed at 6'30 a.m. on May 19 and. the entire i
<br />flood of, about 260,000 acre-feet was safely stored in the reservoir~
<br />Table 2 shows the peaks which actually occurred compared with those:
<br />which would have occurred had there been no regulation by John Mart~n
<br />, Dam.
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