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OIJ~!H -ix- lar€!l3 for a few wc'Jks and inadequately sm.u.l at other timss. Nanifestly there was then. as now. need for reservoirs to aontrol floods, aanserve water supplies, and regulate stream flows in aoaordanoe with irrigation nee ds. However. suitahle storage sites w:lre then thought to he laak- ing, and, to supplement the natural flow of the Unoompahgre River and to irri !;<\te greater acreages, a tumel Yes aonstruoted leading from the Gunnison River to the Uncompahgre Valley. This importation projeat, including oertain main aanals, vas constructed by the U. S. Realamation Bursau, and is one of the early undertakings of that a€!l3noy after its creation by the Reclamation Act of 1902. The project, operated for a nllmber of years by the Reolamation Bureau and later by the Uncompahgre Valley Water Users' Association, inoreased the aareage irrigated in the lo~r seotion from about 30.000 acres to approximately 75.000 aores at the present time. Nothing has been undertaken, as yet, toward con- trollin~ floods in the Uncompahgre River Valley. or oonserving local water supplies or regulating Gtream flows, although recently the U. S. Reclamation Bureau constructed the Taylor Park Reservoir on the Taylor River, whiah unites with the East River at Almont to form the Gunnison River. This Taylor Park reservoir is operated to aid in regulating the now of too Gunnison Rivsr. and while it may in that Yay benefit the Unoompahgre irrigation project, the extent of the benefits to such lands is uncertain and no obligations to repay the cost of the Taylor Park reservoir have baen assUJl1l'ld by or imposed on the Unoompahgre Valley 'Water Users' Assooiation. The Gumison tunnel diverts or exports from the Gunni son River, ~d delivers or imports to the Uncompahgre Valley about 270,000 A. F. fIIlIlually, - equivdent to about 3.6 A. F. per acre irrigated. Togethar with looal supplies averaging 250.000 A. F.. the ocmbined supply avail- able to the 75.000 e.ores irrignted in the to""r Unoompahge Valley totals 520.000 A. F. annually. In their present unregulated condition, some of the local stream flows are undivertible. HOw:lver, by reason of rediver- sions of return flows, tote.l diversions average 540.000 A, F. annually, - eqivalent to a gross re.te of 7.2 A. F. per aore irrig~ted. The investigations disolose that losses in main oanals and la- terals, prinoipally by peroolation. average 95,000 A. F., or 17.6% of the diverted water; that regulation mstes average 80,000 A. F., or 1.4.8% of the diverted water; and henoe that 175,000 A.F., or 32.4% of the di- verted Nl.ter, are not applied to the lands. Fs.rm deliveries average 365.000 A. F., equivalent to 4.9 A. F. per acre normally irrigated. As oompared with rates of diversion and applicrtion in eastern Colorado, the quantities diverted and applied to lands in the lower Un- compahgre Valley are relatively lar@6. In relation to the essential needs of soils and orops under the prevailing olimatic conditions. suoh diversions and applioations are wmeoessarily large. And when evalu- ated in terms of the conveyance or drain8f:e capacities of sub-soils, the