New ordinance requires backflow prevention

WILLIAMSBURG — John Lins, a training specialist with Iowa Rural Water, answered questions last week about a new city ordinance that will require backflow prevention devices for certain city residents.

Backflow prevention keeps water that may have contaminants or pollutants from reversing flow into the public water supply. Those dangers come at cross connections where plumbing fixtures or receptacles, equipment or devices can allow non-potable, used, unclean, polluted or contaminated water to enter the water system when water pressure changes.

The City of Williamsburg plans to add a section to Chapter 90 of City Code requiring that a backflow prevention device be installed at the meter for customers who have cross connections that could contaminate the water supply.

Backflow prevention is already required by state plumbing code, said Lins, but it isn’t always followed. The requirement is supposed to ensure that water can’t flow backward into the water system.

Modern businesses that use chemicals, such as golf courses, car washes, dental offices, funeral homes, factories, pose a danger to the water system if they don’t have backflow preventions, said Lins. He’s investigated these situations, he said. He’s seen it occur.

Contaminated water usually only gets back to the business, said Lins, but if a water main breaks, the water may be pulled back into the water system.

Small communities don’t usually have many threats to the water system, but boilers in schools and care centers will require backflow prevention as will residences that use a hose to irrigate lawns or fill swimming pools, said Lins.

A town the size of Williamsburg probably has about 30 customers who will need the devices, he said.

Iowa Rural Water can help the city with brochures, customer letters and FAQs on the city website to explain the new law to residents.

The city will inspect residences and businesses to make sure they have backflow prevention devices if they need one.

“I’ll help local staff do the inspections,” said Lins. He’ll also have conversations with residents at the time of inspections to answer questions about the requirements.

The city will install a device at the meter — at a cost of about $1,500 — and will have it tested annually by a certified professional at a cost of about $75, Lins said.

City Manager Aaron Sandersfeld said the city will be doing the testing, and it’ll cost about $180.

“We’ve always assumed that the plumbing code was followed,” said Lins, “and we’re finding that it’s not.” Now the city has to take responsibility and make sure these backflow preventers are installed.

The city is requiring that the backflow prevention be at the meter. Whatever they do in their facility, it’s their risk, said Lins. The device at the meter is the only one the city will be testing, said Lins.

The rule will probably not go into effect until after the first of the year, said City Manager Aaron Sandersfeld.