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<br />.42
<br />
<br />FLOODS IN COLORADO
<br />
<br />The widespread floods during June 1864 included Boulder Creek,
<br />for Watrous 22 states that Boulder Valley suffered severely.
<br />The general storm of May 21-23, 1876, resulted in a flood on
<br />Boulder Creek, described in the Greeley Tnbune, May 31, 1876, as
<br />follows:
<br />
<br />The Boulder, swollen into a great river, in placos fully a mile and a half wide,
<br />inundated the land and farms and meadows and swept away fences and bridges.
<br />So far as heard, the damage to farms was not so great a.s the magnitude of the
<br />flood would seem to indicate.
<br />
<br />The Denver Tribune, May 24, 1876, states that Boulder was with-
<br />out railroad service, as both railroads were out of commission.
<br />The severe storm of May 29 to June 1, 1894, was heaviest in the
<br />Boulder Creek Basin, partieularly in the Fourmile Creek area, and
<br />the resulting flood came chiefly from that tributary, which entcrs
<br />Boulder Creek about 2 miles above Boulder. Regarding the flow the
<br />Boulder Camera, May 31, 1894, stated;
<br />
<br />A great flood came pouring down Boulder Creek at an early hour this morning.
<br />Every vestige of a. bridge has been swept away t and railroad tracks torn from their
<br />moorings. [The railroad followed the canyon to Fourmile Creek and continued
<br />up Fourmile Creek to Ward.] From the Boulder Hotel to the University hill
<br />'" . . wa.~ one vast lake with here and there a small patch of lion island.
<br />
<br />The Denver Republican, June 2, 1894, carried a dispatch from
<br />Boulder, dated June 1:
<br />
<br />Boulder and Boulder County yesterday and today experienced the worst Hood
<br />ever known in the history of that place. It had rained for over 2 days, and on
<br />Wednesday night [May 301 it came down in groat volumes. The melting snow
<br />which genera.lly starts the Oood in June was melicd so much faster on account of
<br />the rains that it swelled the mountain stream beyond anything dreamed of. In
<br />the canyon the rush of the stream was maddening and nothing could stay its
<br />downward course. Waterspout after waterspout seemed to break on the hillsides
<br />and added to the fearfully swollen streams.
<br />
<br />Prof. Junius Henderson, writing of this flood of 1894 in the Bouldcr
<br />Camera, November 15, 1921, says that as great damage was wrought
<br />in the canyon above Boulder as in Boulder itself. All bridges wcrc
<br />swept away, and the highway and railroad almost totally destroyed
<br />as far up the canyon as Fourmile Creck, and up Fourmile Creck to
<br />Sunset. He quotes the press as stating that in Fourmile Canyon six
<br />buildings were destroy cd at Crisman, eight at Sunset, and practically
<br />everything was swept away or destroycd at Copper Rocle
<br />In 1912 the Boulder City Improvement Association employed
<br />Metcalf & Eddy, consulting engineers of Boston, who during the coursc
<br />of their studies made an estimate of the peak discharge of the 1894
<br />
<br />II Watrous, Ansel, IIlstory of Larimer County: Conner Printing &: Publishing Co., Fort Collins, Colo.,
<br />1911, p. 213.
<br />
<br />t.':'
<br />
<br />MAJOR FLOODS-SOUTH PLATl'E RIVER
<br />
<br />43
<br />
<br />flood in Boulder. Their report to the Association, dated April 27,
<br />1912, contains the following statement:
<br />
<br />The most reliable record of extreme flood level was that obtained through the
<br />courtesy of the officials of the Denver, Boulder & Western Ry., upon one of the
<br />wooden-trestle bridges crossing Boulder Creek near 4th Street. Here the wide
<br />crossing: is fairly uniform in character for a considerable distance above and helow
<br />the trestle. The slope is approximately 1.1 percent. The reported dept,h was'
<br />about 10 feet at this flood level. [Later reports indicate an area of about 800
<br />square feet, and that this depth may have been as mnch as 11 fect.1
<br />We estimate the discharges corresponding to these elements to ha.ve been
<br />approximately 12,000 second-feet [or 13,600 second-feet with a depth of 11 feet].
<br />In view of what has been said concerning the pooling action of the water at the
<br />bridges, it is possible, however, that the discharge may have been somewhat less
<br />than this-perhaps between 9,000 and 10,000 second-feet. [This discharge is
<br />computed with a value of 0=0.035.]
<br />
<br />On June 2, 1914, another flood occurred in this arca. This was
<br />caused by rainfall on June 1 of more than 1 inch on the North Boulder
<br />Creek Basin near Silver Lake, at an elevation of 10,200 feet. This
<br />rainfall hastened thc melting of the snow, which during the preceding
<br />winter had been 50 pereent above normal. The Boulder Camera,
<br />Junc 2, 1914, described the Good as follows:
<br />
<br />All bridges between Colburn Mill and Boulder Falls were washed out, numerous
<br />others were badly damaged, several hundred feet of main line of Boulder's water
<br />system was destroyed, and thousands of dollars wOJ;:th of damage was done to
<br />Boulder County farm land last night and today by Boulder Creek, which has been
<br />on a rampage for the past 18 hours. * * * The flood was the worst Boulder
<br />has experienced since 1894, when all of the lowlands lying between Water Street
<br />and University Hill were flooded.
<br />According to Water Commissioner James Platt, the creek raised 2 feet 2 inches,
<br />the grea11Cst flow [stage] during the night measuring 5 feet 6 inches. The 2 feet
<br />raise meant an increased water flow of from 2,000 to 3,000 cubic feet [per second],
<br />bringing the total flow up to over 5,000 cubic feet [per second1. This is nearly
<br />4,000 cubic feet [per second] grea.ter than normal.
<br />
<br />Precipitation for June 7-10, 1923, amounted to 3.27 inches at
<br />Boulder, the only station reported in the Boulder Creek Basin. This
<br />storm did not extend 3 miles west to the gaging station near Orode11, as
<br />the discharge at that station was less than 700 second-feet during this
<br />period. The Boulder Camera, June 9, 1923, said:
<br />
<br />Both Middle and South Boulder Creeks have left their banks near Valmont and
<br />a.re cutting between the two bridges of the Valmont road. Wa.t~r is running over
<br />the Valmont road for a stretch of several hundred feet. Twomile Canyon in
<br />North Boulder is reported to be doing gre'at damage to the section lying between
<br />Wellington Heights and Eighth Avenue.
<br />
<br />During the storm of September 1-4, 1938, the basin of Boulder
<br />Creek east of the mountains received precipitation amounting to 3.38
<br />inches at Boulder, and 3.99 inches at Fort Lupton near the mouth.
<br />
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