Chasing a ghost in our water pipes

The Washington State Department of Health has ordered Fircrest to add chlorine to its water system next year.

The reason: portions of our water system have tested positive for the presence of coliform bacteria four times in the past 12 months. Coliform are bacteria that are naturally present in the environment, but are used as an indicator that other, potentially harmful bacteria could be present. Under state rules, a fourth coliform hit in a 12-month period triggers a mandatory order to permanently disinfect the system with chlorine.

According to health officials, all but two of approximately 1,400 water systems in Pierce County add chlorine to their water as a disinfectant. Fircrest and Mountain View Edgewood Water Company are the two. Barring a miracle, that Edgewood system will be the last.

Here’s what we know so far:

Fircrest gets its water from five wells located around the city. (By way of comparison, Tacoma gets its water from the Green River.) The Fircrest Public Works crew takes water samples from various locations once a month.

In November 2014, some of the samples indicated the presence of coliform. When the city gets a “hit” like that, it’s required to immediately go back out and take more samples. In this case, everything came back clean. So there didn’t appear to be a problem. Our Public Works crew suspected the source was road and utility construction in the area last summer, and that some dirt briefly got into the system.

The city’s monthly water tests were 100 percent clean for the next eight months.

Then the August 2015 test detected coliform. That was strike 2. Again, city staff suspected summer construction activity. They retested, and it was still there. So they temporarily added chlorine to the city’s reservoirs to try and kill the bacteria. You may recall some comments on Facebook from folks who could smell and/or taste it. (More on that below.)

The September test detected coliform again. Again, the city temporarily added chlorine to the system and retests came back clean. Still, that was Strike 3.

In October, coliform was detected for the fourth time since November 2014. That triggered a Notice of Violation from the Washington State Department of Health.

All of these hits happened in the north end of the city, near where the city did a lot of construction. In a recent City Council meeting, Public Works Director Jerry Wakefield outlined steps that have been taken to try and solve the problem:

  • Before working on new water mains, the city’s Public Works crew chlorinated each section of pipe and then flushed and tested the pipe before opening it up to the system.
  • As these coliform hits came back, the crew temporarily chlorinated the tanks.
  • They also flushed a few problem areas of the system.
  • They checked with the private lab that handles the tests to make sure nothing has changed.

Every time retests showed a clean system, the crew figured they had solved the problem. That’s why I observed during a recent meeting that it’s like they were chasing a ghost in the pipes. The bacteria kept appearing and disappearing.

A friend of mine is a civil engineer who designs water systems. He’s seen this type of mystery before in other communities. Coliform show up, there’s no success in locating the source, and so the system has to install a chlorination system.

The state’s Notice of Violation results in what regulators call a Bilateral Compliance Agreement (BCA). The state gave the city several deadlines to meet. The first was that the city must sign the agreement by Dec. 10. If the city didn’t sign it, the Tacoma-Pierce County Health Department said it would “red tag” our water system as being out of compliance, which would likely shut down water service to the affected areas (potentially even Whittier Elementary).

Water quality regulators don’t mess around.

So the City Council voted 6-0 on Dec. 8 to sign the order. (Mayor Viafore had an excused absence.) The state’s order gives the city several months to design a chlorine injection system. The city will need four systems to cover its five wells (two wells are on the same property and can be served by the same injection system).

Ultimately, the city and state regulators all want the same thing – safe, clean water. We’re proud of our naturally clean water in Fircrest, and the Council and staff are very disappointed in this situation. The November test came back 100 percent clean. And the city voluntarily tested the system a second time in November, and it too came back clean. However, under state rules, that hit in October triggered the mandatory response by regulators.

It’s important to note there’s nothing wrong with our water at the source — the wells. The bacteria kept showing up in the distribution system — the pipes.

Now, about that smell and taste issue.

Putting chlorine in the water storage tanks a few months ago was a one-time attempt to get rid of the bacteria. It was a sledgehammer approach by design. The permanent solution is more of a surgical approach. Installing high-tech pumps at each well site means the city can inject a specific and small amount of chlorine that spreads it out more effectively than pouring it in the big tanks. The Public Works director says the city should be able to inject a minimal amount of chlorine to maintain a baseline of disinfectant to keep the bacteria away. He believes the small amount injected at the well sites will have a much smaller impact on taste and odor than pouring it in the storage tanks.

Based on our discussion at the Dec. 8 City Council meeting, city staff will be taking steps to notify residents about the situation. Nothing will happen immediately. The city expects to hire an engineering firm to help design the chlorination systems for the well sites. Then the systems have to be ordered and installed. Early estimates are this work could be done in March.

The scope and cost depend on whether additional structures have to be built at the well sites (we’re hoping each site has enough room to accommodate an injection system without additional construction). There’s enough money in the Water Fund’s reserves to cover the up-front cost. The impact on future water rates is unknown, since we don’t yet know the cost of this project.

In the meantime, city staff and health regulators will keep a close eye on water quality. If you want to learn more about this, there’s a ton of information here on the state Health Department’s website about drinking water testing, regulations and responses. Or you can call City Manager Rick Rosenbladt at 564-8901 or Public Works Director Jerry Wakefield at 564-8900.

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