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The Value of Water

Where does our water come from?

When water runs fresh and cool out of the faucet, do you know it all comes from rain? How does it get into the faucet?

The wanderings of water are complex and more costly than you may imagine.

The moisture arrives on our island as rain or fog drip. Some of that water evaporates directly back into the air. Some is taken up by plants, and is either stored in their tissues or re-enters the atmosphere through transpiration. Some runs off in streams and rivers.

And some soaks into the ground and begins percolating downward, filtered as it goes by the soil and rock. The process can take years. A drop that falls high on a mountain can be a generation or more in transit through the soil and rock of our island.

The water continues downward until it ends up floating on heavier sea water which forms the island's freshwater aquifer—the source of our water for drinking and household use.

A healthy rainforest forms an excellent watershed, a place that captures rainfall and dew, limits evaporation, slows the flow of rainwater into streams, and reduces erosion. A good watershed acts like a sponge, soaking up the rain when it occurs, and allowing the gradual release of water into streams and into the ground. It can also help promote recharge of groundwater, and keep streams flowing during non-rainy periods. The Department of Water colaborates with the Kaua'i Watershed Alliance by serving on the Alliance Board and providing some funding to keep our watersheds in good water collecting condition.

Water is a resource with limits…

Groundwater is a major source of clean, cool, fresh water, but it is a source with limits. It is possible to pump an aquifer faster than it can be recharged, so that the water level drops. It is also possible to pump an aquifer so fast that the fresh water is replaced from below by brackish water faster than it can be replaced from above by fresh water. It is also possible to contaminate the water by poor land management practices above. In other words, it is possible to contaminate the source of fresh water we enjoy and it is necessary to be vigilant to promote best practices to prevent this.

Who uses water?

Small meter customers account for slightly more than half of the island's water demand. These customers use anywhere from one to over 2000 gallons of water per day.

Larger meters consume about a quarter of the total Department of Water use.

Government, agriculture, industrial and commercial users represent the remainder. Agriculture users may individually employ a larger volume than others, but most major agriculture ventures operate their own water systems and do not draw from Department of Water pipelines. As a result, agriculture represents less than five percent of the total water use on Kauai.

How the County of Kaua'i Department of Water delivers water to you….

The Department of Water carefully tracks the performance of its island-wide array of 51 wells, 60 tanks, 2 tunnels, 19 booster pump stations and 75 control valve stations. The utility also purchases water from other companies in three of its water systems. The department continually tests its water, to ensure safety. The results of testing, community-by-community, are posted on the Department's website in its annual Consumer Confidence Report. All the systems currently meet federal and state drinking water standards.

The Department has 13 water systems on Kaua'i, each with its own supply, storage and transmission system. Several of those systems are interconnected, to provide backup, and there are nine entirely separate, unconnected systems: Wainiha-Ha`ena, Hanalei, `Anini, Kilauea, Anahola, Lihu`e-Kapa`a, Kalaheo-Koloa, Hanapepe-`Ele`ele and Kekaha-Waimea. The `Anini system uses water from Princeville. The Lihu'e-Kapa`a system gets some of its water from the Waiahi surface water treatment facility.

More than 400 miles of pipeline deliver water to more than 20,000 customers. The Department must ensure that the water is delivered reliably with sufficient pressure, that it is safe to drink, and that there is enough capacity and sufficient pressure for firefighting.

The Department measures water flow to customers with meters for many reasons, including encouraging conservation, ensuring that users pay for the amount of water they consume, detecting leaks in the system and providing a reliable source of revenue to maintain the system.

Our aging water system…

Nearly a quarter of the utility's water lines were installed more than half a century ago and there are miles of pipe that date back as early as the 1920s. The department has an active program to replace aged lines that are leaking or in danger of failing. Some have corrosion issues; others are fragile and susceptible to cracking, while still more have heavy mineral buildups that restrict their flow. Many of the lines were built when demands were lower, and need to be replaced with higher-capacity pipelines. In fact, some of the water system dates back to the plantation era, with distribution pipelines 80-100 years old!

Who needs more water?

While we enjoy the island as it is, it is highly unlikely that the population will remain at its current level. There are many properties that have acquired zoning to build additional dwellings. Water planning is done for properties with approved zoning. This can include small family additions to house aging parents or children returning home from school. It may also include modest rental units as well as some of the larger commercial ventures seeking more water.