Sampling Conducted to Trace Source of PCH Shoulder Water

• RWQCB Testing Will Tell If Permanent Flows Beneath Zuma Bluffs Pose Health Hazards

BY HANS LAETZ

Two ponds full of cattails, reeds and other marshy plants that flourish along the land side of Pacific Coast Highway at Zuma Beach have caught the eye of the water police. Now, homeowners on the bluffs may find themselves with a festering wastewater problem.

Staffers from the Los Angeles Regional Water Quality Control Board took samples at two permanent swales of murky, algae-sprouting runoff along PCH east and west of Guernsey Avenue three weeks ago. The two workers also photographed water seeping out of the bluffs beneath houses on Guernsey and Surfside Way.

Test results are due in late July, and depending on the results, homeowners living on the bluffs above PCH may face mandatory landscaping water cutbacks or be required to replace septic tanks, officials said.

“Here’s a nice wild watercress,” said field tech Toni Callaway, poking at one plant during the early-June sampling session. “I don’t think I would want to eat it, though,” she said, pointing at the murky water oozing from beneath a nearby blufftop house.

“The presence of those seepages during this time of drought indicates that either there is over-irrigation, or effluent from septic tanks gathering on the roadside, said water board chairperson Francine Diamond. It is also possible that someone has bypassed their septic tank with household runoff, which flows through the soil to the roadside swamps, she said.

A third possibility. according to scientists, is that the water is from natural springs. The fact that the water may originate as septic seepage does not means the water is necessarily contaminated as it surfaces. But such a flow could be illegal and harms the environment as it gives bacteria and viruses a place to breed.

Scientists are currently analyzing the samples for nitrites, nitrates, ammonia, nitrogen, bacteria and soap ingredients, said Steven Cain, the board’s executive director. Chemical analysis might detect pesticide or fertilizer residues, which would indicate runoff from landscaping.

E. coli and other bacteria can be traced back to septic tanks, and Los Angeles County is currently conducting a separate study in which human DNA is being sought in polluted creeks to determine if the pollution is of human origin.

The regional water board expects results in four weeks. “The results will go to the City of Malibu, and they are required to order corrective steps,” said Diamond.

“We’re throwing a wide net looking for the typical pollutants that would give us an idea for a source for some of these ponds,” said Cain.

Detailed rainfall and water table levels are kept by the Los Angeles County Department of Public Works at a nearby sewage treatment plant, and an engineer there says years of drought have left groundwater levels in the Trancas Canyon area very low.

Nevertheless, arroyos along the urbanized coast have begun flowing year-round in the last decade, longtime residents say. Overwatering of plush landscaping and a water table saturated with septic tank water being cleansed through the soil may be to blame, scientists said.

In recent weeks, state Department of Transportation workers have bulldozed muck off the road shoulder to allow the stagnant water to better drain into culverts. While that may reduce the ponding at the pavement’s edge, the dirty water is piped under PCH into the sand of Zuma Beach.

Ocean water at Zuma Beach near Trancas has generally tested clean, according to the regularly scheduled testing by the group Heal The Bay.