Page:Report of the Oregon Conservation Commission to the Governor (1908 - 1914).djvu/278

42 Range. The area irrigable from Link River by diverting at the lower end of Upper Klamath Lake is large but the feasibility of most of this project depends upon the character of the tule lands which compose the bed and borders of lower Klamath and Tule lakes. It is not unlikely that 200,000 acres will be ultimately reclmed, but of this a large part lies in California. The total amount of water that can be utilized from Kiamath River in Oregon is probably not far from 500,000 acre-feet.

A large portion of Southern Oregon lies in the interior drainage, a section without an outlet, and commonly known as The Great Basin."

None of the waters of streams rising in this area reach the sea, but instead are lost by evaporation from a series of alkaline lakes or sinks. Large areas of land bordering these. lakes 4a irrigable from the streams-tributary to them. These irrigation developments fall naturally into about 10 projects, for the most part co-extensive with the hydrographic basins of the lakes. In the case of all but one or two of these, practically all the water will ultimately be stored and diverted to the lands. Storage reservoirs are abundant and well distributed and nearly all the valley areas through whieb the streams flow contain as much or more fertile land than can be irrigated by the available water supply.

The one important exception is Ana River, a tributary of Summer Lake. The river rises from springs, none of which ., ,rCmore than 40 ft. in elevation above the lake level. It is posibie to divert their flow with a dan., or by pumping, to lands lying north and east of the lake. As no storage is poSsible only the summer flow can be utilized—say 40 per cent of the total, or 40,000 acre-feet.

The amount of water available from all the other streams of the interior drainage has been taken as 80 par cent of the total, an allowance of 20 per cent being made for evaporation from storage reservoirs and for losses due to excess of water in high years, for which storage cannot be economically provided. The total estimated runoff of the streams in this landlocked area is estimated as 1,220,000 acre-feet or equal to that of Deschutes River at Benham Falls, the portion which can be utilized as 9g7,000 acre-feet.

The total runoff from the 10000 sguare miles drained by the Willamette River is very great but a large portion of the