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Show Record The zero of a gage is an arbitrary point, taken always 4143 below the known bottom of the river. It does not mean anything at all, except as an arbitrary point from which all of the gage charts are referred back. It does not represent depth of water. The gage is simply a means by which the fluctuations from low water to high water can be obtained. On one gage low water might read 20 feet. On another gage it might be 5 feet. Neither the zero of the gage nor the gage heights have any relation to the 4145 depth of the river. A gage height as used by the survey is simply measurement of the surface of the water. It has no relation at all to the depth. 4146 I am able to determine depths and velocities with reference 4147 to certain gage heights which are show on these plates, 1, 2, 3, 4, and 5. 4151 These charts as far as the observed velocities and depths were concerned, were prepared in order that I might show a picture of the depths and velocities obtained throughout the year graphi-cally. 4152 Plate 6 shows for the different gaging stations the number of days, graphically, that the flow was above or below certain amounts between zero and 30,000 second feet. Taking the example at Lees Ferry, based on all the records of stream flow available, the flow has been above 6000 second feet for 295 days, and below 6000 feet for the remainder of the period of each year, with a minimum of 2000. That same data is shown for each of the gaging stations. 4154 Plate 7 shows the velocity in the bed of the stream at the gaging stations. To the best of my knowledge, conditions at the Green River gaging station at Little Valley, as far as the velocities and depths are concerned, represent conditions fairly accurately from the San Rafael to the mouth of the Green. I am unable to give any information as to what extent the records of the gaging station at Bluff indicate conditions on the San Juan. To the best of my knowledge, the Lees Ferry record, as far as velocity and depths are |