City puts backflow prevention at forefront for Horseshoe Bay water customers
By Bill Teeter
The City of Horseshoe Bay is asking residents to take an extra step to protect themselves and their neighbors from contaminants mingling with their drinking water.
In July the City announced that it has begun to require all customers with landscape irrigation to have tests performed on their irrigation system backflow prevention assemblies every five years to make sure they are functioning.
Backflow preventers do what the term indicates: they keep dirty, undrinkable water or other fluids from reversing flow into pipes containing drinking water, whether it be in the public water system or private plumbing.
Backflow preventers are critical to protecting public health. They are required on all irrigation systems connected to public water systems. However, they must be in working condition to fulfill their purpose.
The City is taking this step because the anti-backflow devices often break-down after a period of years. Some studies have found that backflow preventers older than seven years often cannot pass a test for proper function, which means they are no longer reliable for protecting public health.
There are many backflow preventers on sprinkler systems in Horseshoe Bay which are much more than a decade old. Periodic testing helps assure they are working to protect their owners and the public water supply.
Backflow commonly occurs with a pressure drop in one area of a system of pipes. The pressure drop causes a vacuum and pull from other areas of the system. For instance, a water main break could cause a lower pressure in the main, which could lead to a siphoning action pulling from the service lines of nearby homes and yards.
This suction could also pull back water from irrigation lines into the property’s plumbing and the City main line. Water in irrigation lines is liable to carry pieces of grass trimmings, dirt, particles of animal feces, dead insects and lawn chemicals.
Backflow incidents have been documented in other places. For example, in 2015 the City of Corpus Christi tied sprinkler system backflow to e-coli contamination in drinking water lines.
In other cases across the country irrigation systems with inadequate backflow protection have been found to be the source of microscopic worms and debris showing up in drinking water, as well as cases of giardia, a water-borne parasite which causes illness in humans.
Currently, under state rules, in most cases irrigation backflow preventers are only required to be tested upon installation. Cities have the option to add more stringent testing rules which may include periodic testing of all irrigation backflow preventers. This is the action Horseshoe Bay has decided to take.
Other Texas cities and water systems which have chosen to do periodic testing include Round Rock, San Antonio and San Marcos.
To start, the City has divided the City map into five zones. Letters are being mailed to each zone sequentially, with three months being allowed to comply within a zone. Once that zone is complete, the City will move to the next. The intent is to have the entire City covered in about 18 months.
Zone 1, where testing is now occurring, is the northeastern portion of the City bounded by RM 2147 on the south, Hi Circle West on the west, and by Hi Circle North and Lake LBJ on the north and east, and including homes around Broken Arrow and Lighthouse Drive.
Residents with irrigation backflow preventers tested in the last five years should not receive notices until their five-year test date comes up, assuming the tester submitted a report to the City at the time of the test. Also, property owners with systems drawing water from Lake LBJ normally do not need backflow preventers because there should be no connection to the City water system.
Tests should be available for $100 or less.
In cases where the backflow device does not pass, it must be promptly repaired or replaced.
Residents may wait until they get a letter from the City, but they may get their backflow preventers tested before receiving notice if they wish. They may also have their units tested more frequently than once every 5 years.
If you decide to go ahead and hire a tester before receiving a notice, understand that the tester must be registered with Vepollc.com, the City’s contractor for electronic storage of backflow test records. You can find a list of local testers by going to the website and clicking on “Backflow management,” “Registered BPAT list,” and then go to a dropdown list to click on “City of Horseshoe Bay.” Then, click on “Show registrations.”
The list will appear. However, we have included an abbreviated version of the Vepollc .com
For further questions please call me at 830-598-9973.
Bill Teeter is the City of Horseshoe Bay’s water conservation specialist.