,000 acres will be reclaimed.
There is a large acreage in Franklin and Walla Walla counties,
about the junctions of the Snake and Columbia rivers, to which
Pasco is central, which is arid. The government has once turned
this project down, but is now reconsidering it, and it is reported
that these lands will soon be put under ditch by the joint action
of the government and the Northern Pacific railway, which owns
a large portion of the lands.
Meanwhile private enterprises are reclaiming extensive tracts in
Klickitat county, and in fact nearly all the counties bordering on
the Columbia and Snake rivers in eastern Washington. It is probable
that there are more lands capable of irrigation in the state than can
be irrigated with available waters. This fact adds to the importance
of the question of what to do with arid lands when no water can be
put upon them.
METHODS OF IRRIGATION.
There are three methods in use in supplying water to the arid lands.
The first and the one most generally adopted for obvious reasons is
the gravity system. The waters are impounded in lakes or artificial
reservoirs and carried thence in large main canals, winding about
the hills so as to secure a low uniform grade. Once established,
no other force is needed but the usual flow of the water.
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Another method resorted to when the gravity system is impossible
is to pump the water from the big rivers into smaller reservoirs
leading to the canals, the pumps being kept busy only during the
months in which the water is needed. This method is quite successful,
but requires a somewhat larger annual expenditure. It is being
used in some extensive projects, the water being taken out of the
Columbia river.
The third method is in securing the water by means of artesian
wells. This method is naturally limited to small areas, the projects
being undertaken by individual private owners. Several spots have
been found in the arid belt where this method is successful.
SOILS.
The soils over the entire areas of eastern Washington on the arid
lands is a volcanic ash mixed with disintegrated basaltic rocks and
some humus, varying in depth and in the amount of sand it contains.
The low lands are usually more sandy and warmer and earlier in season.
The depth of this soil is in some places 80 feet and generally so
deep as to insure great permanency to its fertility. It readily
absorbs and holds moisture, and is admirably adapted to artificial
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