Flushable wipes blamed for sewer overflow on Mission Creek Road

CASHMERE — A sanitary sewer overflow in the Mission Creek neighborhood last week has the city urging residents to be cautious about what they flush. The blockage, reported the morning of Nov. 17 near 105 Mission Creek Road, was caused by a large mass of so-called “flushable” wipes that built up in the line, according to Cashmere’s water and wastewater staff.

The clog forced wastewater to spill from a manhole before crews could relieve the blockage. Wastewater Services Manager Dorien McElroy said her team responded quickly, inserting a jetter in the nearest access point to restore flow.

“We were able to get the line open, but everything we removed was wipes,” she told the City Council at its Nov. 24 meeting. She emphasized that the products frequently marketed as flushable do not break down in sewer systems.

Under state law, the incident triggered environmental reporting requirements. The Washington Department of Ecology was notified the same day, and the city submitted a detailed five-day written report outlining the cause, cleanup, and corrective steps intended to prevent future blockages. McElroy said the city met the state’s deadlines and provided Ecology with full documentation.

To reduce the chances of another spill, the neighborhood received an immediate education push led jointly by McElroy and Director of Operations Steve Croci. The Public Works team printed door hangers explaining what happened, why it happened, and what residents should never send down their toilets. The handouts were delivered along Mission Creek Road, Creekside Place, Oak Street, and Julie Ann Court.

McElroy said the message centers on what she called the “three Ps” — only pee, poop, and (toilet) paper should be flushed. Any wipes, even those labeled as flushable, need to go in the trash instead.

Crews completed cleanup without disruption to customers, and no injuries or property damage were reported. The affected line continues to be monitored, though McElroy said the bigger safeguard is public awareness.

“This is a neighborhood issue, not a mechanical issue,” she said. “If people understand the impact, they can help us prevent the next one.”

Residents with questions about wastewater system maintenance or proper disposal habits can contact Cashmere Public Works through City Hall.

Andrew Simpson: 509-433-7626 or andrew@ward.media