Water-use auditor Michael Marquez with Tucson Water has been asked to investigate a mystery: Why did customer Robert A. Sumner's water use spike this summer?

As an auditor in the utility's 15-year-old Zanjero Program, Marquez helps a customer figure out how to save water. Advice is as simple as plugging a leak and as complex as installing a gray-water system.

"Zanjero" refers to a water manager during Tucson's days as a Mexican town. The zanjero ensured that water rights were legally allocated to farmers, says Fernando Molina, who developed Tucson Water's program.

Marquez also helps customers like Sumner, whose issue isn't about saving water. His 1970s midtown home already has low-flow showerheads and toilets and a tankless water heater. He manually turns on the drip system to water a moderately sized landscape, manually fills his pool and controls his two evaporative coolers with thermostats.

The retired construction worker wants to know why his bill jumped in one billing cycle. The mystery deepens because the family had gone away for a week in that time and in the next cycle, water use went back to normal.

"If there's an issue, I'd like to correct it," Sumner says.


Marquez starts with the major water-wasting culprit: the toilet. He checks each of the three commodes in Sumner's home to make sure they're operating correctly. He confirms they aren't running excessively when refilling nor are they leaking.

A good test for a leaking toilet is to put food coloring in the tank and wait 20 minutes. "If the color is in the bowl, the flapper needs changing," says Marquez.


Marquez then checks the water heater to make sure it's in working order.

A tankless system heats water as it's drawn. It can be installed in a central area or at each faucet.

The system saves water by eliminating the need to run water for a few minutes until it's warm enough to use.


Marquez heads outside to read the meter. It can tell him whether there is a leak.

A customer also can learn more about how water is used. "The best tool for the customer is that meter," he says.

The meter has a dial, a counter and a small, red triangle, which detects low-flowing water. If no water is flowing through the system, none of these should be moving.

If any of these are moving when all water appliances are turned off, turn off the house water valve, Marquez advises. If the indicators stop, the leak is in the irrigation or the house. If any are still moving, it's a leak in the service line.

By subtracting the numbers on the counter before and after you use water, such as for filling a pool or irrigating your landscape, you can figure out how many gallons you use for the task.

In Sumner's case, the triangle slowly turns, which Marquez attributes to the coolers running. It whirls a few seconds after someone flushes a toilet.


Stumped, Marquez can't find what might have caused the spike. He says that a house sitter may use a bit more water to irrigate inside and out. "When you're watching a house, you don't want anything to die on your watch," he says.

This doesn't apply to Sumner, however, who didn't use a house sitter.

Marquez advises Sumner to see if he qualifies for a bill adjustment.

Tucson Water's courtesy adjustment program is designed to partially compensate for unexpected high water use such as from a line break or leak, says utility spokesman Molina. A customer can receive one adjustment in a three-year period.

More zanjero tips

• Check Tucson Water and government agencies for rebates or tax credits on water-efficient appliances and parts.

• Besides toilets, the biggest water wasters are pools that automatically fill and water softener systems. Check those systems regularly.

• Consciously listen for running-water sounds. Residents often miss leaks because they don't hear the signs such as a filling toilet.

• In evaporative coolers, make sure the bleed-off line is clear. Regularly clean off mineral deposits throughout the cooler. Direct water runoff to plants.

• Read your meter once a week. If you recognize a spike, you can deal with it quickly instead of discovering it on your next bill.

Get a water audit

Any Tucson Water customer can request a free analysis.

Zanjero Program auditors will inventory your indoor and outdoor water use, provide information on saving water and install free faucet aerators and showerheads.

Customers who benefit most from an audit typically consume more than the average 13,000 gallons, or 18 ccf (hundred cubic feet), a month, says Fernando Molina, the utility's spokesman.

However, "we find that many customers want to learn about what they can do to save even more water," says Molina.

An audited household in which conservation measures are taken saves an average of 92 gallons a day.

To make an appointment, send an email request to TW_Web1@tucsonaz.gov

The resident must be at the home during the two-hour survey.

The WaterSmart Business Program makes audits available at commercial sites. For more information, call 791-4331.

Contact local freelance writer Elena Acoba at acoba@dakotacom.net