Bloomberg Law
March 17, 2020, 10:22 PM

Avoid Fatbergs, Don’t Flush Wipes Due to Virus, California Says

Emily C. Dooley
Emily C. Dooley
Staff Correspondent

People cleaning to avoid the new coronavirus shouldn’t flush disinfectant wipes or paper towels down toilets because they could clog drains, back up sewers, and cause overflows at sewage treatment plants, California’s leading water regulator said Tuesday.

Wipes have long been an issue because wastewater treatment plants depend on gravity and water flows, and aren’t often designed to deal with paper towels or wipes, even those labeled flushable. Those items also don’t break down like toilet paper.

The problem has taken on new urgency with the spread of coronavirus, which causes the illness Covid-19.

“Preventing sewer spills is important, especially during this Covid-19 emergency, for the protection of public health and the environment,” the State Water Resources Control Board said in a public advisory.

The wipes can catch on tree roots and gather fat, oil, and grease, becoming large rags that block pipes, according to the California Association of Sanitation Agencies, which has a “Wipes Clog Pipes” public education campaign.

“This problem is experienced across the state, country, and worldwide as disposable wet wipe products become more widely available,” the association said.

London ‘Fatberg’

In late 2017, crews in London, England, used high-powered jets of water and hand digging over three weeks to remove a 40-ton so-called “fatberg” from the sewer system where it was blocking 80% of the capacity.

The Ross Valley Sanitary District, which oversees 200 miles of sewer lines and 19 pumping stations in Marin County north of San Francisco, has seen an increase in towels, wipes, and rags getting into the system in the past week or so, General Manager Steve Moore said.

“We really don’t want our system to overflow,” Moore said. “If it isn’t addressed, it could compound on us.”

Apartment complexes are of particular concern. “There’s not a lot of space to absorb a bunch of nondegradable items,” he said.

A bill in the California legislature would prohibit product labels from claiming they are safe to flush, or OK for sewer and septic systems, unless they meet certain regulations. Other products would require clear labels warning that a product isn’t flushable. AB1672 passed the Assembly in January and is awaiting committee assignment in the Senate. California’s legislature is on recess until April 13 due to the coronavirus.

Washington state’s legislative houses have passed a similar bill and another has been introduced in Minnesota, according to the National Association of Clean Water Agencies.

To contact the reporter on this story: Emily C. Dooley at

To contact the editors responsible for this story: Gregory Henderson at; Chuck McCutcheon at; Anna Yukhananov at