The Los Angeles River is riddled with dangerous levels of fecal material and other harmful pollutants, a new study says.

In a statement released Wednesday by watershed scientist and lead author of the Katherine Pease of Heal the Bay, an environmental group that monitors the water quality of swimming areas, the researchers said that " on a chronic, long-term basis."

"The findings are a cause for both concern and opportunity, given the growing recreational uses of the river and a $1 billion revitalization plan for L.A.'s central water body," Pease said.

Pease and her team of30 regular "stream team" testers collected and tested water samples weekly over a three-month period last summer for fecal indicator bacteria at severaldifferent sites in the recreational areas of the Elysian Valley and the Sepulveda Basin.

"Bacteria levels varied among the sites in the new L.A. River study, but overall were quite high," wrote Pease, noting that samples for one type of fecal indicator bacteria, Enterococcus, exceeded federal standards 100 percent of the time at Rattlesnake Park and Steelhead Park in the Elysian Valley. In the Sepulveda Basin, levels exceeded federal standards 50 percent of the time and at Rattlesnake Park, levels of E. coli exceeded federal standards 67 percent of the time.

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"The study shows that popular recreation spots along the Los Angeles River suffer from very poor water quality, which poses health risks to the growing number of people who fish, swim and kayak in its waters," Pease said.

These health risks include ear infections, respiratory illnesses and gastrointestinal illnesses for people who come in contact with the water, Pease said.

Revitalizing the Los Angeles River

The Los Angeles Daily News reports that river advocates and city officials have been working to it once was until the U.S. Army Corps of Engineers transformed it into a concrete flood control channel in the 1930s.

However, the new study could put a damper on those plans.

While the group lauded "recent efforts to revitalize the L.A. River and to open up public access to recreational zones," they concluded that "water quality improvements are needed to expand these opportunities and protect public health."

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According to the press release, the Army Corps of Engineers has an approved $1.3-billion plan to revitalize an 11-mile stretch of the river, which will focus on habitat and recreational improvement.

"Heal the Bay strongly urges that rehabilitation work incorporates specific and measurable measures to enhance water quality," Pease said in the release.

Safety Precautions

The group, which also advocates for funding for comprehensive water-quality improvement projects, recommends that people avoid swimming in the L.A. River and sporting enthusiasts like kayakers and anglers limit water contact. The group also called for increased monitoring and public notification.

“The public has a right to know about water quality conditions in the L.A. River so that they can make informed decisions on how to minimize their risk of getting sick,” said Rita Kampalath, Heal the Bay’s science and policy director, in a statement to the Daily News. “We look forward to working with the city and recreation outfitters to improve outreach and monitoring measures along the river.”

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At a Glance

Los Angeles River has levels of bacteria that exceeds federal guideline, a study revealed.Health risks include ear infections, respiratory illnesses and gastrointestinal illnesses for people who come in contact with the water.Group that conducted the study recommends people avoid swimming in the river.