Nooksack irrigators, other heavy water users should face water-use-efficiency scrutiny

Because the Pacific Northwest is so wet in the winter, it’s hard for many of us to recognize the water-supply problems we face. Because of climate change, the summer supply of water throughout the Nooksack River basin is declining. And because of climate change, and to a lesser extent population growth, summer demand for water is growing.

This supply/demand imbalance is a serious problem but not yet a crisis. However, if we don’t act soon, it will become a crisis, in which salmon and other wildlife decline and then disappear, farmers can no longer irrigate their crops, and we may not have enough water to support our industry, commercial businesses and homes.

We can reduce this supply/demand imbalance in three ways: increase supply, store winter water for summer use and increase water-use efficiency (WUE) across all sectors. Over the past two decades, our local Watershed Management Board has sponsored several studies on supply and storage options. But we have yet to consider, even in a cursory fashion, the benefits and costs of WUE. Because we have never seriously studied WUE, we have no meaningful programs in place to encourage more efficient use of our increasingly scarce water supplies.

The board recently sponsored a detailed study of six storage options, ranging in cost from about $100/acre-foot of summer water provided (enlargement of Springsteen Lake) to a dam on the North Fork at more than $1,400/acre-foot. This study examined capital and operating costs for each project, as well as the winter benefits (reduced flooding), summer benefits (increased flows), regulatory hurdles, environmental issues and other factors that would affect feasibility.

We desperately need a similar study of WUE technologies, practices and programs. Such a study would examine existing programs in Whatcom County as well as those offered throughout the West, including ones run by the U.S. Bureau of Reclamation. Reclamation has run efficiency programs to increase storage in the large Colorado River reservoirs at about $400/acre-foot.

In response to state legislation from 2003, all water utilities run efficiency programs. Traditionally, these emphasize consumer education. Recently, local programs, coordinated by the Whatcom Water Alliance, expanded to offer rebates for purchase of efficient clothes washers, toilets, showerheads and other water-using equipment. These programs should focus more sharply on reducing irrigation use in the summer. For example, a $10 timer could prevent lawn and garden overwatering and save both money and water.

Analysis of water-meter data for 2,600 Lynden single-family homes showed that the top 10% of households used three times as much water in the summer as the average home. Programs that target high users will save much more water and cost much less than an undifferentiated program for all utility customers.

Because agricultural irrigation accounts for about 70% of Whatcom summer water use, we should focus on equipment, maintenance and scheduling practices that save water. For example, a new 360 Rain system is being tested on a local farm.

This highly automated, remote-controlled system, discharges water much closer to the ground than conventional big gun systems, thus eliminating most wind drift and evaporation. As a consequence, this system is almost twice as efficient as traditional irrigation systems. If widely adopted, such technologies could save many thousands of acre-feet in Whatcom County. A key question here is who would pay the high capital costs for these new technologies.

At the other end of the cost spectrum, improved irrigation scheduling can also save lots of water. A system developed by Washington State University could save 10% or more. This software, which resides on a smartphone, uses current and past weather conditions to forecast weather for the next week and an associated seven-day irrigation schedule. And this software has zero capital cost, making this method very cheap to implement.

Experience in other parts of the West suggests that local use of efficiency technologies, practices and programs offers some of the least expensive, most flexible and environmentally benign ways to reduce the looming gap between growing demand and declining supplies. Water-use efficiency alone will not solve our problems. But it must be an important part of the overall package.

Eric Hirst, a retired energy policy analyst, is a long-term environmental activist who has lived in Bellingham for 20 years.