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Spring 1983

Summer 1983

Action! (Marion Saunders)
League Testifies at Legislative Hearings
Voters Service (Marian Wilkins)
Juvenile Justice (Catherine Filson)
Around the State
Water (Linda Lai Hipp)
Legislation on Water (Linda Lai Hipp & Anna Hoover)
Energy (Joan Davenport)
Reapportionment Update (Anne Lee)
State Convention
LWV of Hawaii Proposed Budget 1983-84

Water

"Life on earth is bound inextricably to the presence of water. It is the one unvarying necessity of all living things." This statement by William Ashworth says all in telling the importance of water in our lives and yet hardly begins to explain its use in our society. Not only does water give us life, it gives us comfort and pleasure as well. For generations we have lived in an environment rich with water. Yet since the industrial age began, we have shown no respect for its limits in availability and misuse. Only careful planning for the future will safeguard this precious resource.

The State of Hawaii possesses great supplies of water but they are not evenly distributed throughout the islands. Most of the current demand for water is in dry, sunny areas where agricultural yields are highest and most of the population resides. No change is foreseen in this use pattern for the future except that demand will increase significantly due to continued development. There are one or more water-short areas with the potential for more development on all the major islands. With demand greater than supply, needs must be met by importing water from wetter areas. Generally, all islands have sufficient water to meet the demand through the year 2000 except Oahu, where projected demand will begin to tax the sustainable yield of fresh waterfrom presently developed sources by that time. The cost of developing new water sources is expensive, whether it be from fresh water or desalted brackish and/or sea water. Ultimately, the consumer will bear the cost.

Hawaii has both surface and ground water. About 45% of the water used in Hawaii is surface water in streams and ditches. The remaining 55% of Hawaii's water supplies, including most of the domestic water, is from ground water sources.

The availability of surface water in any area within the islands depends largely upon the amount and frequency of rainfall. Numerous streams originate in the heavy rainfall belts of the islands but if their flows are not diverted for use, they quickly find their way to the sea or infiltrate to ground water storage. Rainfall averages about 70" per year and results in adequate water resources to meet most needs. However, because of unequal rainfall distribution, there are areas with surplus water and areas short of water on all islands. Steep, narrow valleys and generally pervious rock formations common on most islands provide few good sites for large surface storage reservoirs. There are such sites on Kauai, Molokai and Hawaii but they will be expensive to develop. Instead, use of surface water will probably involve the diversion of water from wetter to dryer areas.

Ground water is that portion of water that infiltrates into the ground and recharges underlying reservoirs. Ground water supplies are being developed more and more for all uses because of the unreliability of surface water supplies. There are three ground water sources in Hawaii:

  1. Basal water - lens-shaped bodies of fresh water floating on salt water either freely or confined by coastal caprock under artesian pressure.

  2. Dike-impounded - water - water trapped in rock formations at higher elevations.

  3. Perched water - water trapped above both basal and dike-impounded systems.

Basal water bodies provide most of the ground water supplies developed in the islands. Because of inadequate man-made storage, summer peaking needs are met by increased ground water pumping. When discharge exceeds recharge, there is a danger of salt water intrusion.

Dike-impounded water bodies are important sources at higher elevations. When developed by tunnels, this water can be transported by gravity to areas of use. This tunneling has destroyed the storage capacity. Restoration of some areas could provide valuable storage for summer use.

Most perched water bodes are small and quickly drained after rainfall. Yet these are important water sources at high altitudes in isolated places.

Linda Lai Hipp

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