Laserfiche WebLink
<br />done in its interpretation of the mass diagram analyses. An <br /> <br />additional investigation is required to accurately quantify <br /> <br />these return flows and to determine what adjustments to <br /> <br />streamflow records are needed to reflect what the natural <br /> <br />flows would have been without transmountain return flows. <br /> <br />3. Selection of an Index Flow <br /> <br />For purpose~ of the mass diagram analyses, the index <br />flow or index inflow was defined as Purgatoire River at Las <br />Animas plus the flows of the Arkansas River at Canon City. <br />Records of streamflow at the Canon City gage were adjusted <br /> <br />for transmountain diversions into the basin above the gage <br /> <br />to maintain a consistant record for the complete study <br />period of 1908 to 1984. The Arkansas River at Canon City is <br />located upstream of the major diversion points on the <br /> <br />Arkansas River and is an indicator of upstream inflow from <br /> <br />the higher, mountainous regions of the basin. Normally, a <br /> <br />/~ <br />, <br />i <br /> <br />o <br /> <br />majority of the streamflows in the Arkansas River Basin <br />I <br />I <br />I results from precipitation in the drainage area above Canon <br />l City. The fact that most of the dependable runoff in the <br />basin originates above Canon City is ~videnced by the <br />locations of the majority of the irrigation development <br />which has occurred along the main stem of the Arkansas <br /> <br />River. <br /> <br />The Arkansas River drainage basin below Canon City is <br /> <br />generally characterized by broad, gently undulating plains. <br />The major tributaries below Canon City are mostly intermit- <br /> <br />tent, and ~heir contributions to the flows of the mainstem <br />of the Arkansas River are limited except during floods <br /> <br />:~ <br /> <br />-26':' <br />