21 SOURCES AND STORAGE OF IRRIGATION WATER CI
and transportation of distant waters to areas of the valley which
would develop a water shortage. This plan of ultimate development B.
and integration of water resources of the state is now being imple-
mented, and supplemental waters are being diverted and stored in the
ground-water reserves which were seriously deplted.
With the development of new techniques of exploration for ground
water, with increasing control and understanding of weather, and
with decreasing cost of mechanical energy incident to the atomic age,
water supplies can be made available to areas ofshortage which at C.
the present time appear to be impractical. Thql re, the definition
of "safe-yield" is changing and will continue tof1nge as economic
and technological conditions change. Certainly, and reclaimed
surface waters cannot be stored in sub-surfa voirs until ca-
pacities are created in these reservoirs by wH al of existing
Safe-yield also implies a wise balance where ce ssve and un- D.
economical pumping lifts are not imposed, nor ious deterioration
in water quality permitted. It is important to der "safe-yield"
in. th ligbt of total water resourqqe: sutce surface, devel-
o o0 diid, tial., .......... E.
2.14 FEASIBILITY OF GROUND-WATERi OPMENT
Undue lowering of ground water results in er pumping lifts
and sometimes prohibitive pumping costs. W eg may need to be
deepened and pumps lowered in order to o btain cient quantities
of water. The extent of irrigation pumping. pm ground-water
supplies should therefore be determined on thqe'asis of thorough,
long-time investigations of the quantity of an fow or recharge
to ground-water streams, basins, or reservoirs. cal
Essential decisions concerning development und-water sup- grc
plies for irrigation can be made after cho e" or "no" on up
twelve important points, listed in the f4lowj onnaire. There
answers shown are generally considered as ind ing that ground-
water supplies can be developed satisfactorily.. in
A. Availability, quality, and depth of water:
1. Is a plentiful supply of waterr available? yes
2. Is water of the right quality available to per- ,
mit production of the desired crops? yes
3. Is water available at a depth that will permit
economical pumping? ',A yes