Congressional Serial Set Volume 6249 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913 Excerpt: ...at Yuma, Ariz., far 1902-1912--Continued. Note.--Daily discharge determined by the indirect method for shifting channels, puled by engineers of the United States Geological Survey. Monthly values comCOLORADO RIVER BELOW YUMA, ARIZ. Duiing the period 1903--1906 the United States Geological Survey made frequent measurements and installed gages at a number of points on the lower Colorado River and Imperial Valley canals. It was during this period that the flood, described on page 32, occurred. The following descriptions and data apply to the work done at that time. COLORADO RIVER BELOW HEADING No. 3 OF THE iMPERIAL CANAL. Measurements at this point were begun July 12, 1905, as so much water was at that date going down the canal that it was simpler and more economical to measure the water in the old channel of the Colorado than to continue the measurements on the canal itself. In the center of the river, opposite heading No. 3, was an island nearly a mile long. The channel on the west side of the island was about 600 feet wide; that on the east side was about 800 feet wideAt first the discharge was measured at a point below the island, but by August 15 a sand bar had formed from the island to the west bank of the river below the heading, and all water passing down on the west of the island entered the canal. August 31 a gage was established above the head of the island, and after that date all discharge measurements were made at the head of the island. Measurements were not made at one certain point, but at any favorable cross section among the shifting bars oi mud and quicksand that could be reached and measured by boat or by wading. The old channel continued to silt up gradually and the new one to scour deeper, and October 20, 1905, all the water was carried ...