Sludge Watch ==> North San Joaquin Calif - More Human than Cattle Bacteria in Waterways

[Maureen Reilly]

Sludgewatch Admin:

Sludge tycoons and their noisy touts have been falling over themselves to 
blame cattle for polluting the waterways of California (and killing people 
who eat tainted spinach).  But this study shows mostly human DNA 
contaminating waterways in the North San Joaquin Valley.  That means looking 
at sewage treatment plants, sludge spreading, septic tanks.

And don't forget that sewage treatment plants, sludge spreading, and septic 
tanks may all contain cattle DNA from wastes disposed from meat packing 
plants, slaughterhouses, and rendering plants.
So human sludge disposal can still infect people with Ecoli 0157 from 
cattle.
....................................................................................



Water trouble may not be from cattle

It's mostly human bacteria seen in waterways studied


By JOHN HOLLAND
BEE STAFF WRITER


Last Updated: January 9, 2007, 07:15:35 AM PST


A study commissioned by a farmers group suggests that humans, not livestock, 
are the main source of certain bacteria entering waterways in the Northern 
San Joaquin Valley.
The study authors cautioned that the findings are tentative, but if they 
hold up, they could influence the debate over how farmers manage runoff from 
irrigated land.

People involved in the study said much ofthebacteriadetected at the 27 
monitoring sites in Augustcouldhavecome fromfailingseptic systemsorother 
sourcesofhuman waste,ratherthan fromlivestockmanure.

"Everyone was kind of thinking thiswas going to be a cow problem, butit's 
not," said Wayne Zipser, executive manager of the Stanislaus County 
FarmBureau.

Zipser is a leader in the East San Joaquin Water Quality Coalition, which 
commissioned the report. The coalition, representing the east side of the 
valley from Stanislaus to Madera counties, is one of several formed by 
Central Valley farmers in an effort to meet tightened rules on runoff.

The study, by three experts at the University of California at Davis, 
followed up on earlier detection of E.coli, atype of bacteria that can 
sicken people, at some of the sites monitored by the coa-lition.

The new study looked not for E.coli, but for bacteria from the genus 
Bacteroides. These microbes contain DNA specific to their sources — human, 
livestock or others — and can be a general indicator of how bacteria 
movethrough a watershed.

At almost all of the sites, human DNA was found far more often than the 
cattle or chicken versions. At two sites, one near Waterford and one east of 
Turlock, human and chicken DNA were equal but cattle DNA was a tiny 
contributor.

"We were surprised it turned out the way it did, the fact that human DNA is 
so high in almost all the samples,"saidleadresearcher Michael Johnson, 
director of theAquatic Ecosystems Analysis Laboratory at Davis.

Wildlife and pets also can produce bacteria in waterways, but the study 
authors left them out because of limited funding.

Attorney Brent Newell, a frequent critic of valley agriculture, said the 
study is of little value because it measured only the relative shares of 
DNA, not the actual amount of E.coli.

He also said the study dealt onlywithcreeks,irrigation drains and other 
surface water,not the groundwater many rural residents drink.

"Anybody that tries to make a statement here that agriculture is not a 
source of E.coli is vastly overstating the conclusions," said Newell, who 
works for the Center on Race, Poverty and the Environment in San Francisco.

The farmers coalition sends itsdata to the Central Valley Regional Water 
Quality Control Board, which aims to prevent pollution of the Sacramento and 
San Joaquin rivers and their many tributaries.

BoardspokeswomanLiz Kanter also noted the lack of E.coli data in the study.

"We want to know more — what the scope of the work entailed, how random was 
the sampling," she said. "It's not conclusive for us."

Second sampling is likely

Coalition chairman Parry Klassen said another round of sampling will likely 
be done this winter to see if storms have any effect on movement of 
bacteria.

He said human sources of bacteria could include illegally dumped portable 
toilets or "vagrants" relieving themselves near the sampling sites.

"It's unlikely that it's sewage treatment plants, because they have to 
comply with permits," Klassen said.

Kanter said the state is moving to tighten controls on septic systems, which 
when working properly allow waste to break down harmlessly in soil.

Klassen noted that farmers own many of the septic systems in rural areas. 
These systems are not under the farm runoff rules, which deal mainly with 
containing water tainted by pesticides, livestock waste and fertilizers.

Johnson and his co-authors on the study, Lizabeth Bowen and Melissa Turner, 
stressed that their findings are only a start.

"Clearly," they wrote, "much more research needs to be conducted before we 
can confidently understand the behavior of bacteria in these systems."

Fresno Bee staff writer Dennis Pollock contributed to this report.

Bee staff writer John Holland can be reached at 578-2385 or 
jholland at modbee.com.

http://www.modbee.com/ag/story/13179384p-13821920c.html