WaterSmart helped save East Bay Municipal Utility District customers 5 percent in water use during a recent pilot. Five percent may not sound like a lot, but it is when every drop counts.

The independent findings from the large pilot, which included 10,000 customers, are the latest results from WaterSmart that confirm savings of 5 percent. WaterSmart is often called the Opower of water because it uses behavioral science, neighbor comparisons, and customized efficiency tips to drive conservation.

WaterSmart has slowly been expanding in recent years and raised an additional $4.5 million last summer to expand nationally. The San Francisco-based company works with thirteen utilities in California, Colorado, Utah and Texas.

Water infrastructure across the country is desperately in need of upgrade. The price of water is rising proportionately faster than electricity in the U.S., according to nonprofit journalism group Circle of Blue. Even though money is tight, water investment increasingly cannot be ignored. The EPA reports that the U.S. loses about 6 billion gallons of water from leaks every year. California is in the midst of its third year in a row of drought, with many cities recording record-low precipitation.

But it will likely be California, which is requiring its water utilities to slash use by 20 percent per capita by 2020, where WaterSmart will likely find the most uptake in the short term.

The independent one-year study in the East Bay Municipal Utility District found that households that use the most water tend to save even more when using the program. The top quartile saved about 6 percent, while the lowest quartile saved about 3 percent. Interestingly, paper reports were found to be more effective than emailed reports.

 “We were targeting a 2 percent increase in conservation, and our customers achieved 5 percent,” Richard Harris, EBMUD manager of water conservation, said in a statement. “The WaterSmart program exceeded our expectations, plus helped us increase our customer engagement.”

The median unit cost of saved water was only slightly higher for paper versus email reports, about $400 per acre-foot compared to $380. That is far lower than the median unit cost of $700 per acre-foot that the California Water Foundation identified in 2012. The cost per household per year is about $5 to $7, depending on the report delivery method.

As other WaterSmart pilots have found, one of the upsides is not just the savings, but also the fact that households that receive the reports are about twice as likely to participate in audit and rebate programs.

As is the case with electricity, many people have no idea how much water they use at home. In the one-year pilot, however, those who received reports didn’t fare much better than those who didn’t when it came to estimating average daily water use. One reason for this could be that WaterSmart reports focused on gallons used per billing period, rather than per day, during part of the study period. It could also be that the behavioral feedback simply needed more time to educate and influence people.

“It is also not obvious to us that a quantitative knowledge of daily water use is particularly relevant to most decisions about household water use,” the report authors state. It might be more important to know how to shop for a water-efficient clothes washer than to know specifically how much water the household is using.

Many of the findings from the large pilot are lessons that water utilities could have plucked directly from their electricity brethren when it comes to new consumer programs: good data management is key; customer service representatives need to be trained in the tenets and strategies of the program; and phasing in the program gradually allows for tweaks as it scales up.

Moving forward, EBMUD is evaluating how frequently to send the reports and how to ensure the savings are durable and do not fade over time. Although questions remain on how to get the most from the reports, EBMUD is expected to expand its program with WaterSmart in coming years.