January 7, 2020
San Juan Islands’ fresh-water supply sustainability is in question
Mike Sato

Reporter — and former well-digger — Mike Sato digs one San Juan County’s 5,000 wells, in a 1970s-era photo courtesy of Lopez Island Historical Society.

January 7, 2020
San Juan Islands’ fresh-water supply sustainability is in question
Mike Sato

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Back in the ’70s, the Lopez Island water witch and other old-timers would rattle a newcomer’s cage by telling him the water feeding wells in the San Juan Islands came from a large undersea aquifer reaching to Mount Baker.

Fifty years later, the water witch and the old timers are gone, and the specter of climate crisis is here. No one jokes about fresh water in the islands coming from Mount Baker. Instead, talk is in earnest and concerns the question of sustaining the islands’ supply of fresh water.

Climate changes will bring both longer, hotter, dryer summers and saltwater intrusion in fresh water aquifers. The county has drafted an action plan that identifies how legal battles may arise over water rights and water use. But planning is hampered by some valuable missing information.

A climate crisis resulting in fresh water shortage would curtail the tourism economy, county collection of real estate taxes, and employment in construction and hospitality sectors.

Over the last 50 years, the islands’ population has grown from 3,900 to nearly 17,000 year-round residents. During summers, the population doubles to nearly 35,000 with tourists and seasonal residents.

On the other hand, the islands’ population is projected to grow only to 19,400 by the year 2036. If no tourists visited and no second-home owners came during the long, hot climate-crisis year of 2036 — an unlikely scenario — there might be enough water. But without water data, no one can say.

Running dry in summer — now

Already, summer drought conditions and increased water use routinely prompt water rationing in some larger water systems. Some wells go dry for a period each summer. The drought years of 1979 and 2015 saw many wells run dry or deepened or supplemented with storage tanks to increase holding capacity, according to the San Juan Islands Resilient Community Action Plan: Water, 2017.

But the capacity of water from wells in the county is unknown, making it problematic to predict future needs.

Anyone drawing water from a well near the shoreline where the sea level is rising may feel the effect of the climate crisis much sooner. These days, on San Juan Island, shoreline wells go dry in the summer and are recharged with water trucked in.

Water supply management is complicated by regulatory jurisdiction, officials say.

“The state regulates large Class A water systems that serve 40 percent of the population,” said Paul Kamin, chair of the county’s Clean Water Utility District Advisory Committee. These larger systems are metered and supplies controlled. Nine large systems draw water from lakes and reservoirs, according to the action plan.

Usage? unknown for 40%

Of water from the county’s 5,000 wells tapping into various island underground aquifers, “the county regulates smaller Class B water systems serving 20 percent of the population. But nobody regulates the individual wells serving 40 percent of the population,” Kamin said. All the latter are unmetered, so usage is unknown.

There hasn’t been a complete study of groundwater resources, said San Juan County commissioner Jamie Stephens — and the issue of monitoring private well water use is politically charged.

“Individuals can draw up to 5,000 gallons a day. It would be good to know how much is being used,” Stephens said. However, he has heard, “Why would I want anyone to know how much water I use?” in response to the notion of reporting on private well usage.

“The San Juan Islands have a single source for all of our freshwater resources: precipitation. The rain that falls on each island is the only way our lakes and ponds are refreshed, and our groundwater is recharged. The fresh water on each island is isolated by the surrounding seawater,” the action plan notes.

Each winter, the rains fill the lakes and reservoirs but only five to nine percent of the rainfall recharges the aquifers. The rest of the water evaporates, is absorbed into the soil or runs off into the sea.

The San Juan Islands get an average annual precipitation of 28 inches. The action plan says that, despite climate change, precipitation should remain at historic levels.

One effect of future longer, hotter summers and shorter rainy winters is that the intensity of the rainfall may increase as well, resulting in more runoff from the land and less recharge of the aquifers.

Planners question of whether individual household wells are withdrawing water faster than the individual aquifers are being recharged. Without knowing the capacity of individual aquifers, amounts of water being recharged or amounts of water being withdrawn, there is no way of knowing whether there’s sufficient recharge by rainfall or whether islanders are “mining their water” — withdrawing more than is being replenished.

Sea level rise, another effect of climate change, would increase salt water intrusion into wells along the island shorelines where the lens of the fresh water aquifer is thinner. The problem intrusion has progressed over the years as more shoreline wells have been drilled and more water withdrawn.

Problems with water availability in the climate crisis may spur more desalinization technology, more impoundment of rain water, direct recharge of aquifers and advanced direct grey water discharge technology.

Several desalinization systems already serve shoreline dwellings in the islands, including a subdivision on San Juan Island. Rainwater catchment systems are allowed for single-family dwellings throughout the islands.

Metering key for adapting to future

The county’s action plan recommends a wide range of tactics that the county can incorporate into its planning and building rules to adapt to the climate crisis. These include:

  • metering newly drilled wells
  • voluntary metering of existing wells
  • identifying priority aquifer areas
  • adopting smart metering
  • requiring bi-annual water depth measurements for private wells
  • designing water system use rates to encourage conservation
  • increasing education regarding indoor and outdoor water use.

Many of these tactics have been recommended for adoption by the county in its comprehensive plan currently being updated, Kamin said.

He ventured an estimate that the county’s comprehensive plan may be adopted by the end of 2020, after which time action elements of the water plan will be worked on.

One bright spot is that the county’s stormwater utility assessments now include funding for water planning.

Planning is one thing, action another. Nothing provokes action like a crisis — but with only one source of fresh water, a crisis of water availability in the San Juan Islands would not be easily fixed.

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