× Dismiss

Never Miss an Update.

Water Deeply is designed to help you understand the complex web of environmental, social and economic issues contributing to the drought crisis in California. Our editors and expert contributors are working around the clock to bring you greater clarity and comprehensive coverage of the state's water issues.

Sign up to our newsletter to receive our weekly updates, special reports, and featured insights on one of California's most pressing issues.

How Leaky is Your Water Utility? Soon Californians Will Know

A new state law requires large California water utilities to begin reporting losses in their distribution systems, which are wasteful and expensive. Todd Thompson of the Department of Water Resources explains the process.

Written by Matt Weiser Published on Read time Approx. 7 minutes
Aptopix sinkhole
A Los Angeles fireman looks under a fire truck stuck in a sinkhole caused by a burst water main in the Valley Village neighborhood of Los Angeles on Sept. 8, 2009. California has introduced a requirement that large water utilities file audits of water loss.Nick Ut, Associated Press

California’s drought has required water consumers to adopt a wide range of water efficiency practices, from taking shorter showers to installing water-sipping appliances. But what have water utilities been required to do?

It’s long been known that water distribution systems have leaks, and most utilities work to correct those leaks aggressively, because they also represent lost revenue. But every leak also represents a cost to ratepayers, not to mention a wasted natural resource.

How much do water distribution systems leak? That’s been a big unknown. Common estimates are around 10 percent, but some systems may leak as much as 45 percent.

Soon Californians will know exactly how much their water utilities are leaking. Senate Bill 555, a law passed by the state Legislature in 2015, requires large urban water utilities – those treating more than 3,000 acre-feet (3.7 million cubic meters) of water annually or with more than 3,000 connections – to file water loss audits starting in October. There are 410 utilities subject to the law.

To help understand the law, Water Deeply recently spoke with Todd Thompson, a senior engineer at the California Department of Water Resources, who is in charge of drafting the regulations.

Water Deeply: Is this completely new in California?

Todd Thompson: The reporting requirement is completely new. But there are quite a few water suppliers conducting audits either on their own volition as a good practice, or as a part of being with the California Urban Water Conservation Council, which requires its members to estimate losses. I believe somewhere around 60 percent of the 410 large suppliers are already doing some form of water loss audit.

Water Deeply: Why is it important to create a formal process and make the results public?

Thompson: It’s part of improving best management practices on the water supply side. And it is a first step in improving system operation and efficiency.

You conduct a water loss audit to get an estimate of where the water is going and how much is being lost as a result of either meter errors, water theft or actual leaks in the system. The water loss audit is the first step in making that determination. It’s important in California, as it is everywhere, to make sure we use our resources as wisely as possible and as efficiently as possible. Water loss auditing is a step in that direction.

Water Deeply: How much do we know about water loss today?

Thompson: There have been estimations made. I’m reluctant to cite those because I really have never been able to put my finger on the data where those numbers came from. I’m not sure how accurate it is, so I really don’t want to push numbers that may not have really any value to them. But the rule of thumb is around 10 percent. But it can be higher than that.

Water Deeply: But this is really about more than water losses, right?

Thompson: It definitely is. By being efficient with the water that’s being treated and transmitted through distribution systems, a utility can definitely reduce its operations cost, because it’s not losing water that they’ve put value into. In addition to that, it is a way to make sure, if there are any real losses happening that would impact the infrastructure in the area – such as roads and buildings – they can catch those before they become a real problem. There have been plenty of places where a leak has gotten bigger, to a point where it swallows cars or does significant damage to the roads.

In that regard, it’s more than just being proactive toward water conservation. It actually makes good sense in terms of fiscal responsibility – and liability, to some degree – when you talk about damage to roads and existing infrastructure.

Water Deeply: What are other states doing about managing water loss?

Thompson: To the level that we are looking at for our requirements, the only state that has an equivalent program is the state of Georgia. That was also a result of a drought they went through. They are at least six years ahead of us. I think their law started in 2010. They’ve had good acceptance with it and actually we are using some of the info they’ve learned in our program. We have gained from their experience.

Water Deeply: Is tracking water loss difficult for water agencies?

Thompson: It’s work, but I would say it’s not difficult. They have the data and it’s a matter of gathering the data and putting it into an audit format. There’s some work required, but since they already have the data it’s not extraordinarily difficult for them to do it. The validation step is something that isn’t as widespread, so there will be a learning curve with that. But I don’t think that will be very difficult either. Ultimately, it’s not very hard.

Water Deeply: How does the validation work, and why is that important?

Thompson: Validation is basically looking at the data that’s in the audit itself to make sure it accurately reflects the utility. The methodology that’s being pursued is the American Water Works Association methodology. They basically give a scoring for each of the data fields. That is, how strong is that data itself? It looks at how many meters there are on the source putting water into the system, how often those meters are calibrated, and those factors produce a score to see how well it reflects the utility’s practices in the water system. It’s all intended to make sure the information is accurate.

Water Deeply: How often will water agencies be required to submit audits?

Thompson: They ultimately will be submitting them annually through our website. The first submittal date is Oct. 1, 2017, and annually thereafter. The period they can audit is either the calendar year or the fiscal year. We did that so municipalities can use auditing techniques that suit them best to serve their needs for their fiscal purposes and planning purposes.

Water Deeply: What’s left to do to approve the regulations?

Thompson: We have a process to go through. We’re in the midst of a 45-day public comment period now. Then we’ll have a public hearing on it, respond to all the comments, make changes as appropriate, and either recirculate it or take it before the California Water Commission for adoption. The water commission has to approve them and I’m hoping to have it in front of them by May.

Water Deeply: Will the public have access to the water loss reports?

A woman leaps over water flooding a side street after a water main break sent churning, muddy water down Sunset Boulevard in West Hollywood, Calif., on Sept. 26, 2014. From October 2017 large water utilities in California will have to file audits of water loss in their distribution lines. (Nick Ut, AP)

A woman leaps over water flooding a side street after a water main break sent churning, muddy water down Sunset Boulevard in West Hollywood, Calif., on Sept. 26, 2014. From October 2017 large water utilities in California will have to file audits of water loss in their distribution lines. (Nick Ut, AP)

Thompson: Yes. We already have a website for water loss audits, where all the documents will be posted.

All of the agencies subject to these regulations have gone through at least one water loss audit already, because that’s required in their urban water management plans. Those are available on the website now. We’ve looked at that data and we’ve had experts look at it. And what they told us is that it’s very hard to pull any conclusions from this data, because it’s not validated.

Water Deeply: How will the data be used once the audits start piling up?

Thompson: There’s going to be performance standards established that will require California water agencies to reduce their water losses. The State Water Resources Control Board will be setting those performance standards, but not until they have two years of validated data. The industry strongly pushed for that to make sure what comes forward as a result of this program is based in solid numbers.

I think you’ll see a required minimum validation score, meaning they want strong data. And there could be a “percent of water supplied” number put forward as the performance criteria for losses, too. The state board will have a public process to establish that. The industry will get to weigh in, and it will be discussed at length. That was the idea of the statute: Something will be imposed to control water losses.

Water Deeply: What’s the end game? Is it better water efficiency, more daylight on water losses?

Thompson: The end game will be on several fronts. Certainly water efficiency will go up as a result of the program on the water supply side. I think the public will be better served, because water agencies will be more aware of their water losses and therefore be more efficient with the water resources they’re handling. It may not reduce their operating costs, but it could. It will certainly be more efficient in terms of their operations, which will benefit the consumer.

I think it will also reduce real losses, which could reduce infrastructure damage as a result of leaks down the road. And it’s going to be validated data, so you have an idea how good the data is. But you’ll also have an idea of how efficient they are being in terms of reducing their losses, which ultimately consumers are paying for.

Never miss an update. Sign up here for our Water Deeply newsletter to receive weekly updates, special reports and featured insights on one of the most critical issues of our time.

Become a Contributor.

Have a story idea? Interested in adding your voice to our growing community?

Learn more