Oregon Coast beaches are contaminated with poop. That’s the finding of a new report released by Environment America: 70 percent of West Coast beaches showed unsafe fecal contamination levels during at least one test day, and Oregon's beaches punched in at 86 percent.

The research is based on tests of 3,192 beaches by the National Water Monitoring Council, conducted last year. Of the 21 Oregon beaches tested, Manzanita Beach clocked the highest percentage of unsafe test days (90 percent), followed by Harris Beach State Park (86 percent), Seal Rock State Recreation Site (83 percent), and Rockaway Beach (82 percent). Cannon Beach was mildly better, at 63 percent. For comparison, Alaska and Hawaii beaches averaged 23 percent unsafe days.

The report notes that contaminated water is typically caused by stormwater runoff, sewage overflows, and manure from industrial livestock facilities. Private septic systems are also a major driver of beach fecal contamination. Resulting health ailments can include gastrointestinal illness, ear and eye infections, and skin rashes.

The new report joins a waterfall of warnings by the Oregon Health Authority, which conducts year-round beach screenings and consistently issues public health advisories, like this June advisory for Oceanside Beach, and late May warnings for Nye Beach.

For now, the only advice is to swim with your mouth closed and hope for the best.