OCR Text |
Show 122 I Average depth is not a factor in navigation . . A table of stream flow records may show an average depth of 3 feet , but that is no benefit in determining the value of the stream for boats because such figures may be made up from depths ranging as low as six inches over bars and riffles . The observations at the various gaging stations are the best evidence of variations in depth , and detailed studies are contained in ( Compl Coilipl ) . Exhibit 82 and Compl . Exhibit ( 82-A 82A ) from which the following conclusions are drawn : Green River at Greenriver , Utah . ( -On On ) Plate 2Y Compl . Exhibit ( 82-A 82A ) , it is shown that the ( mean inean ) depth at the ( gaging gacring ) station varies from less than 3 feet with discharge of 2,000 ( second-feet secondfeet ) to a mean depth of somewhat over 12 feet at flood stage ( of" of ) ' between 30,000 and 40,000 ( second-feet secondfeet ) . As shown on Plate 9 the mean depth at the gaging station ford half of the time is less than 4.2 feet and less than 3 . feet for 53 days on the average each year , but ( these' these these- these ) depths do not obtain over riffles or sand bars . Depths in channel of Green River below Greenriver , Utah . - ( Exceptions 26 and 39 . ) The detailed study of the physical characteristics of Green River ( Compl . , Exhibit 75 ) shows that during the periods of low and medium flow shallow depths were invariably ( en- en ) countered across the head of the various riffles above the mouth of the San Rafael and across shoals , or bars which exist in straight stretches between . |