The Topanga Underpass is the only designated underpass in the Malibu area meant for pedestrian use, but county officials are worried about a water quality problem that’s developed from humans treating the underpass like a bathroom. Scientists believe human waste is tainting nearby water.
The underpass, located on Pacific Coast Highway west of Topanga Canyon Boulevard, is owned by Caltrans. Several posted signs encourage visitors to “Please Use the Pedestrian Underpass to Topanga State Beach” to avoid crossing the busy PCH. But once accessed, pedestrians find graffiti-laden walls and officials admit transients and passersby tend to “take care of business” in the tunnel.
Caltrans, along with county and state park officials, said this week there are no immediate plans to curb problems of human waste in the underpass, which is likely polluting the nearby Topanga Lagoon and State Beach. California State Parks, which owns land on the north side of the underpass, has stationed a ranger nearby for many years to help clear out transients and help curb the ongoing graffiti issues.
But, the pollution problem persists.
Rosi Dagit, the senior conservation biologist at the Resource Conservation District of the Santa Monica Mountains (RCDSMM), has been studying water quality in the area since last year and said fecal contamination, even just one “direct deposit,” can significantly raise bacteria counts at the beach. Though there are restrooms available for public use nearby, people passing through and transients who sleep there rarely use them, Dagit said.
“The big problem with the Topanga underpass is some people who go under there don’t want to take advantage of our restrooms. We call this fecal contamination ‘human direct deposits’ and it gets washed down to the Topanga Lagoon,” Dagit said.
With the help of scientists from UCLA, the RCDSMM has been testing to identify contamination sources since last year.
Official water test results will not be available until October, but Dagit is certain none of the fecal contamination is from surrounding septic systems or the upper watershed.
“LA County hired us to identify the source, and the source is a human contribution resulting from humans not using the bathrooms at the underpass,” she said. Instead, they use the underpass as their bathroom.
Dogs are a part of the problem and birds contribute naturally as well, according to Dagit.
“We can control the human direct deposits and the dog deposits,” she said.
Patrick Chandler, public information officer from Caltrans, said tackling this issue is a big project that would require joint efforts.
“Generally, [Caltrans] will post a notice in English and Spanish giving 72 hours for people to gather their personal property. As far as fecal matter, we will work with a hazardous material contractor if it gets to that level,” he said.
Kelly Markham, also a PIO for Caltrans, said the agency plans on sending crews Friday, May 23, to assess graffiti in the underpass but that keeping transients away and people from going to the bathroom is a “law enforcement issue.”
“Caltrans has no authority to prevent people from defecating on walkways, however … crews have said that on occasion [they] have noticed feces on the walkway and cleaned it up,” Markham said.
Chandler said graffiti is a huge problem throughout LA County.
“It costs us millions of dollars per year,” he said.
The RCDSMM does not own any part of the Topanga underpass, nor is responsible for any of its maintenance and upkeep, but contributes by monitoring water quality in the Topanga Creek. LA County got RCDSMM involved in 2013 when a Beach Report Card gave the area a poor grade. LA County Department of Beaches and Harbors media contact Carol Baker said her agency is solely responsible for maintaining the beach at Topanga.
“Caltrans owns the highway and the underpass bridge and is responsible for the maintenance and upkeep of it,” she said.
