Goleta Water District customers have been raising concerns about high levels of water-treatment byproducts in the system, and the board of directors noted Wednesday that it’s an issue the district has been monitoring for a long time.

Trihalomethanes, abbreviated as THMs, are byproducts of drinking water disinfection, and are one of the many contaminants the district tests for with water-quality monitoring.

There are state and federal standards for THM levels, and the Goleta Water District is compliant with those standards, General Manager John McInnes said.

Noozhawk has received emails and copies of Facebook messages from Goleta-area residents regarding the levels of THMs in the water, and concerns about potential health impacts from high levels.

One resident, Caroline Bennet, had her shower water independently tested and it found high levels of THMs, of 150 parts per billion, which is almost double the maximum contaminant level goal of 80 parts per billion.  

“I recently moved to Goleta, and since then my skin burns and itches after I shower, and my eyes sting. My daughter has the same problem, and so does my next-door neighbor,” she said in a message to Noozhawk.

“I emailed Goleta Water and they said it only matters if the average of the whole year (four quarter results averaged) are below the health limit. It does matter to me because I am showering in 150 (ppb) right now, and it is extremely uncomfortable.”

District water quality testing reports for 2016, the last full year available, show a maximum contaminant level goal of 80 parts per billion for total trihalomethanes (TTHMs). The system average that year was 69, with a recorded range of 5.7 to 130 parts per billion.

“We’re paying quite a bit of attention to it,” board president Rick Merrifield said Tuesday night, in response to a public comment about the THM levels.

The district has plans for short- and long-term steps to take to deal with the problem, which has a lot to do with drought impacts and runoff from recent wildfires, he added.

“We do expect more and more organics to get into Lake Cachuma, and we pump our wells pretty hard,” he said.

Those specific steps were detailed in a special meeting Wednesday for the water management and long-range planning committee.  

Years of drought and wildfires have caused more organic matter (decaying vegetation and runoff from burn areas) in the Lake Cachuma water supply, and chlorine used in water treatment processes reacts with organic matter to create THMs, district engineer Daniel Brooks said.

For its THM-reduction program, the district is looking at treatment and storage options to deal with organic matter, chlorine dosage, and “water age,” which is the amount of time between water being treated and being delivered to the customer.

Reducing the water age is a way to reduce THMs, Brooks said.

While researching treatment options for more long-term solutions, the district is trying to reduce water age by reducing storage in distribution reservoirs and flushing the entire distribution system to lower the demand of chlorine in water treatment.

The district is also using groundwater-only to meet demand in winter months, since it “contains very little organic matter and therefore does not pose a THM problem,” according to district staff.

The district doesn’t know what a permanent, long-term solution will be, or what it will cost, but staff will bring back recommendations for action in a few months.

Scroll down to read the staff report on the THM reduction program from Wednesday’s meeting.

“Clearly this has been on our radar for a long time,” Director Meg West said.

West said water-quality discussions can cause some people to have “fear-based reactions” and the district isn’t hiding anything with the THM levels.

If people are having skin irritation, the district doesn’t know if there’s a correlation to their water quality, McInnes briefly noted.

The district’s consumer confidence reports on water quality advise people with sensitive skin to talk to their doctors, and a memo on the website about water quality mentions filters as well.

“Because the water in the region is very hard, and people have varying preferences for water, individuals may wish to consider additional filters or water softeners to offset the naturally occurring minerals in the water that are not completely removed by the treatment process,” the statement says.

Organic matter in the water supply will be a continuing problem for the South Coast, and the district’s plan is forward-looking, Director Lauren Hanson said.

“While the district’s potable water currently meets drinking water standards for THMs, increasing levels of organic matter in Lake Cachuma are expected to drive THMs beyond the current treatment capabilities of the Corona Del Mar Water Treatment Plant and above the regulatory standard, which would trigger notification to customers as required by law,” Brooks wrote in a staff report to the board.

District staff also pointed out other local and California water districts that have had THM levels high enough to trigger customer notification and enforcement action.

“In Santa Barbara County alone, according to the Drinking Water Enforcement Actions website of the State Water Resources Control Board, agencies required to notify customers of THM violations between 2013 and 2017 include Carpinteria Valley Water District, Central Coast Water Authority, Cuyama Community Services District, City of Santa Maria, Montecito Water District, and Vandenberg Air Force Base,” Brooks wrote in a staff report.

Goleta Water District THM Reduction Program 

— Noozhawk managing editor Giana Magnoli can be reached at gmagnoli@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.