Department of Water Resources
A daily compilation of significant news articles and comment
June 16, 2008
4. Water Quality –
Students tackle mysteries of ocean pollution
San Jose
A stretch of
The
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Students tackle mysteries of ocean pollution
San Jose
By Pat Brennan, Orange County Register
Later, with the local beach culture on full display outside, a battalion of students and young scientists crowded into a nearby trailer, hovering over funnels, dry ice buckets and liquid nitrogen containers as they prepared water samples for analysis.
It's the start of a summer-long study meant to answer some of the most vexing questions in the world of water pollution: Are swimmers really getting sick? Do standard contamination tests really work? And can faster, more accurate tests be developed?
"It's all geared toward changing the way we do beach monitoring," said John Griffith, a lead researcher in the study by the Southern California Coastal Water Research Project, as he drove the low-speed vehicle back to the trailer with his samples. "We want to give an answer the same day and measure something that's relevant to public health."
The study at Doheny, visited by some 1.8 million people a year, will be combined with a similar effort in Avalon on Santa Catalina Island off the
In
But bacterial warning signs still go up, and surfers still complain of earaches, sore throats and other infections. For many water-quality scientists, uncertainties have increased in recent years about just what is being tested and how reliably the ocean water tests can flag traces of human sewage.
"We've got to try to find something better," said Steve Weisberg, the research group's executive director.
While scientists have been questioning swimmers and sampling ocean water for decades, the two rarely have been done together. In this study, while one group takes ocean samples, another, led by UC Berkeley, recruits beach visitors, sometimes entire families, for the second half of the project: tracking their swimming habits and illnesses over a period of weeks.
There are weaknesses in both methods of assessing the likelihood that a dip in the ocean will lead to the sickroom. Questionnaires and surveys might capture people who think they got sick from the ocean, but in reality, contracted their illness from food or one of the many other places where people cross paths with disease-causing microorganisms.
On the other hand, contamination tests of ocean water typically take 24 hours to yield a result. That means people swimming in contaminated water often don't know it. And by the time the signs go up, the ocean might no longer be contaminated.
By matching the water samples with interviews of beachgoers in real time, the scientists hope to get a far more precise picture of how the complex stew of microbes that wax and wane in the near-shore ocean affects the human bodies immersed in it.
Doheny is one of
The samples prepared in the trailer are destined for a variety of universities and other institutions across the country, where scientists will use them to try out new ocean-water testing methods.
"It looks pretty much like chaos, but everybody knows what they're doing," said Monica Mazur, a retired county water quality specialist, who volunteered to help prepare the samples.
At least two critical scientific questions are driving these efforts. The first centers on the time lag between sampling and results, which means many bacterial warnings are out of date before they are even publicly posted.
Scientists at the
The second problem could cast into doubt the ocean-sampling methods that public health agencies nationwide have relied on for decades.
The most common tests measure types of bacteria that are normally harmless, but are thought to be present in a water sample whenever human sewage is there, too.
These "bacterial indicators" act as proxies for disease-causing organisms.
The problem is that these indicators are among the most often-used bacterial species. Enterococcus might be shed by animals, or might be growing on their own in the environment, in rafts of dead algae and other places.
Recent studies suggest that the bacteria used as sewage indicators could be thriving where no sewage at all is present. And if they are flushed out to sea, they can cause water sampling tests to give false alarms, prompting the posting of warning signs where a true threat of disease might not exist.
That doesn't just ruin a day at the beach. It means city governments might be spending millions cleaning up creek mouths or stretches of beach that were never contaminated in the first place.
"A huge bill has to be paid by municipalities to fix what essentially could be a non-problem," Weisberg said.
Knowing what the indicator tests say when people are actually in the water is a critical step toward resolving the problem.
The only other recent Southern California study that combined water-quality testing with beachgoer interviews, in San Diego County's Mission Bay five years ago, showed almost no illness at all during times when counts of indicator bacteria were high. That suggests that the bacteria might, in some circumstances, be unreliable indicators of disease-causing organisms.
For the Doheny researchers, even beachgoers who never set foot in the ocean are important.
"We need a control group of people who don't go in the water,"
One of them, Mary Petersen, 76, of
"I'm in favor of anything we can do to clean up the water along the coast," she said.#
http://origin.mercurynews.com/breakingnews/ci_9595733
A stretch of
The
By Rong-Gong Lin II, Staff Writer
Seen from its banks, the
But in this stretch, just southeast of
Still, they live in spots littered with plastic bags, foam cups, beer bottles, spray paint cans and smashed shopping carts.
So on Saturday morning, more than 2,500 volunteers, most of them teenagers, showed up at the
Most of the helpers were members of the Pacific American Volunteer Assn., which brought in students from as far away as
Some of the teens squealed in disgust at the sight of the river. Others took on their mission with gusto.
Sergio Hernandez, 15, and his soccer teammates from Eagle Rock High School gingerly stepped on slippery stones to get to a dirt island in the middle of the shallow, slow-moving river.
There, sheltered by trees, lay a tiny stream flanked by thickets. Sergio's friend, Andre Cousineau, 15, used a wooden stick to keep a foam cup from floating down the stream.
"I got it," Sergio said, using his own tree branch to scoop the cup into a bulging plastic bag. It was already filled with a dirty blanket, soda and aerosol cans, and a potato chip bag.
"This bag is heavy," he said, before leaving for the riverbank.
Some of Sergio's friends stumbled at times, but they said the experience was fun.
"We have to help out the community," said Juan Llano, 16, whose white T-shirt was grimy with remnants of leaves and dirt.
Just north, 10-year-old Jidam Lee of
"It's messy," said Jidam, poking the claw into the green muck below. "Eww! Monster yuck!" he said, after finding a slimy cloth.
Farther upstream, 16-year-old Tai Hyuknahn carried a bag of trash, while Ruby Choi, 16, and her 11-year-old brother, Ken, plucked litter out of the river.
"It stinks bad," Tai said of the scent of moss wafting in the air. "It's disgusting. The smell will get to you. I doubt fish could swim here."
"This is better than the zoo," Ruby replied.
Catherine Mims Yamaguchi, 47, of
"I didn't know there was so much life here," Yamaguchi said. "I thought it was a stagnant pool."
For Dwight Taeza, 56, of
"I grew up in the
Sisters Becky and Liz Landeros said they wished there had been an even greater turnout.
The river is much worse south of the
Heavy rains during the winter caused the river's water level to rise, trapping litter in the trees "10 feet in the air," said Becky Landeros, 19.
Mark Gold, president of Heal the Bay, an environmental group involved in coastal and groundwater quality advocacy, said the massive turnout was important for the environmental movement.
Now the
http://www.latimes.com/news/science/environment/la-me-river15-2008jun15,0,4754399.story?track=rss
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