Laserfiche WebLink
<br />D R AFT <br /> <br />SECTION III - WATER AUGMENTATION POTENTIAL AND <br />ESTIMATED BENEFITS <br /> <br />" <br /> <br />Cloud Seeding Areas <br /> <br />Most of the flow of the Colorado River originates from seasonal <br />snowpack in the alpine and subalpine watersheds where winter precipi- <br />tation amounts are high and evapotranspiration losses low due to <br />colder temperatures. These important runoff-producing snowpack <br />watersheds cover only a small part of the Colorado River Basin. <br />Since these high-elevation watersheds are also on mountain barriers <br />where winter orographic clouds occur, applying weather modifica- <br />tion over these small areas to significantly augment the Colorado <br />River becomes a reasonable possibility. Summer precipitation usually <br />does not provide a significant contribution to the total basin <br />runoff. <br /> <br />,. <br /> <br />The major runoff-producing areas (fig. 3) of the Upper Colorado <br />River Basin have been identified as the 14,200 square miles with over <br />10 inches annual runoff 11/. The estimated average runoff or speci- <br />fic yield from these areas is about 13 inches. Additional or secondary <br />areas yielding 1 inch to 10 inches annual runoff total some 9,500 <br />square miles, with an average annual runoff of about 3 inches. The <br />entire upper Colorado River watershed above Lee Ferry, the dividing <br />point between the Upper Basin and Lower Basin, is 109,500 square <br /> <br />12 <br />