Even in Hawaii it is essential to plan ahead and carefully shepherd our water resources for both the near and long term. It requires a head shift because on the islands we always expect water to come out of the tap, and the idea of a water scarcity seems so foreign. It is foreign, but it is also closer to home than we might think.

I recall, while living in the Middle East in the early ’70s, when a bottle of water cost more than its weight in gasoline. For ages, sweet water in that part of the world has been a scarce resource. Reverse osmosis, a method of extracting drinkable water from salt water, is in full swing. It works well but it is energy-intensive, so there is a substantial cost. We used RO fueled by solar panels on the Hokule‘a during some of the longest legs on the worldwide voyage. It worked well.

Chennai, a city of 9 million people in India, has essentially run out of potable water. Clean water is trucked in and is available only to those who can pay. This leaves slum dwellers dying en masse. Reservoirs, lakes and wells there have run dry after two years of low rainfall as Chennai heads into another dry season. The drought is evidenced from space. Water scarcity has affected the economy, education, health care and visitor infrastructure. Rainwater catchment has become law. Many of India’s largest cities and others worldwide are facing similar problems.

Could Hawaii run short of water? When we hit the 8 million-visitor mark a few years ago, I wrote a column arguing that headroom (hotel accommodation) and airlift (airline seats) plus infrastructure were maxing out, and made a case for developing the health and wellness visitor industry. An old friend from the Department of Economic Development and Tourism, commented that one day Hawaii will be like Singapore, which has four times the population on one-quarter the landmass. I’ve begun to realize he may be right. Visitor numbers are now around 10 million, more airlines are opening new flights and Airbnb has facilitated what would appear to be an endless resource of headroom including so many “monster houses.”

Hawaii loves to hate the rail project so much that one gets the sense that its construction will always be a problem and that it might never get built. But it will, and Hawaii will continue to develop infrastructure inexorably over time — more sewage, more solar energy — and the need for water will only grow.

RevoluSun, one of Hawaii’s largest solar companies, has expanded into the smart-home space and now offers air conditioning. RevoluSun put solar panels on my roof years ago. When it came to install AC last month, the foreman described intense demand for cooling systems and PV panels for energy.

It’s definitely getting hotter in Hawaii, and the rainfall patterns are changing. Climate change brings not only the risk for reduced precipitation; it also changes when and how the rain comes. Remember the deluge and flooding last spring?

The problem is that in places where water is generally abundant, we don’t manage it as well because it doesn’t seem to be a priority — until it does. The causes and conditions are gripping: increasing numbers of visitors and residents, the rampant rate of construction and the associated need for all manner of infrastructure, not the least of which is fresh water.

There is much to be done to conserve and manage Hawaii’s sweet water. To do so calls for public and private efforts and, on an individual level, an appreciation of a personal responsibility to care for our most precious resource.

Ira Zunin, a practicing physician, is medical director of Manakai o Malama Integrative Healthcare Group and Rehabilitation Center and CEO of Global Advisory Services Inc. Please submit your questions to info@manakaiomalama.com.