With water conservation a hot topic across Texas and the nation, Stephenville’s City Council and Department of Public Works are currently taking a look at the costs vs. benefits of replacing or updating the city’s current, aging water meters with much-improved, radio-read technology.
Nick Williams, director of public works, explains the problems with the aging meters and the advantages of the metering project under discussion.
“We’ve got an issue with our unmetered water percentage climbing a little bit higher than what we want, between seven and 13 percent. It bounces back and forth and that’s part of the problem; it shouldn’t do that. So we had Johnson Controls come in and - at no charge - they did a study for us and found that quite a few of our meters were inaccurate.
“The older they are, the less accurate they become. Well over 50 percent of the city’s residential water meters were measuring less than the American Water Works Association, or AWWA standard. That means they were less than 95 percent accurate.”
He points out that the meters’ inaccuracy does not cost the water user more money. In fact it costs them less because failing meters typically underreport usage.
“When a meter fails, it almost invariably fails ‘down,’ meaning it registers less [water usage] not more.”
But the water that’s being used has to be paid for by someone and thus the inaccurate meters cost the city money.
“The fact that we have really hard water here is a factor,” Williams said. “We all have stories about water heaters and coffee makers and those kinds of things failing faster than normal. Our water is at 314 parts per million (ppm) and the EPA says that hard water starts at 150 ppm; we’re more than double that. The hardness, the calcium carbonate in the water tends to build up on the insides of the meters because they’re a brass component. If you can picture a small paddlewheel inside the meter, that mineral build up slows down the function of that rotating mechanism and they become very inaccurate at low flows.
He continues, “What this project does is it replaces those failing meters with a type of meter with no moving parts. The new meters are made of a polymer composite that’s actually stronger than the brass meters. They’re guaranteed to maintain 98.5 percent accuracy for the life of the meter, which is expected to be 20 years. We hope to gain more than 20 years out of them.”
Asked about costs, Williams says, “Local government code says a municipality can have an energy-saving project like this if the revenue generated from the improvements makes the payment for the project. In other words, the revenue has to be more than the cost of the project.
“We’ve structured this project so that we have a positive payback starting in year one so we’re not in the hole until year ten when we pay it off. It’s a guaranteed 10-year payback, but the city sees an increase in revenue in year one simply because the inaccurate meters will have been replaced with accurate ones.”
Williams points out that this wouldn’t be an across-the-board swap out; if a meter is less than five years old, it wouldn’t be replaced until it tests as inaccurate. “We’ll retrofit a fully-functioning meter with a radio rather than replace it at a much higher cost.”
Whether new or retrofitted, meters with radio sending units would allow the city to monitor Stephenville’s water supply system more accurately and in real time. Williams also explained that it would make it possible to redirect some of the efforts by the city’s present-day manual meter-reading staff into the customer service area.
“The system will give us the ability to access reads much more than once a month. Typically it will be set up to take readings once a day. So if you were to go on vacation and you have a leak while you’re gone, we’d find it the first day rather than you coming home to a flooded front yard,” he said.
Mayor Kenny Weldon said the council still needs to make a final decision before implementing the program.
"Even though it is a low-cost initiative it does count against the debt ceiling for the city," Weldon said. "That’s not to say that we’re not going to do it, just that we’ll be talking about it one more time. But at this point the dollar amount we’d be saving and the improvements to infrastructure definitely look good.”
The council is slated to discuss the issue in July.