Study seeks to tie creek bacteria to its sources

Published: Sunday, January 30, 2005 at 6:01 a.m.
Last Modified: Sunday, January 30, 2005 at 1:19 a.m.
Her first instinct was to immerse herself in the problem.
But when Robin Hallbourg learned the extent of sewage contamination in Gainesville's urban streams, the Alachua County geologist thought better of it.
"Until I thoroughly looked at all the data, I used to take my son on these creek cleanups," Hallbourg said during a recent interview from her Union Street Station office.
Now, she said, "I don't take him anymore."
It's no secret Gainesville creeks need cleaning. Long hot spots for fossil hunting and recreation, garbage and visible refuse make some segments appear more like urban sewers than valuable natural resources.
But water quality experts say it's what you can't see that may be most troubling.
Throughout the Gainesville drainage system, miles upon miles of surface water are contaminated with fecal coliforms bacteria.
Gainesville Regional Utilities has begun an investigation to genetically match fecal waste to its sources.
Fecal coliforms bacteria, which is found in the feces of people, wildlife and pets, pose little human health risks, according to information from the U.S. Environmental Protection Agency Web site, but they do indicate the presence of bacteria that cause typhoid, dysentery, hepatitis A, and cholera.
"Fecal coliform is an indicator that human sewage is getting into the water," Hallbourg said. "We want to make sure that we're not discharging sewage directly into our surface water. People play in (it)."
It isn't clear how widespread Gainesville's fecal contamination problem is. While local environmental groups have been monitoring sewage in city creeks since the mid-1970s, recent changes in testing methods make comparing earlier results difficult, Hallbourg said.
But a series of high-profile spills by Gainesville Regional Utilities in 2003 caught the attention of state and local regulators. In July of that year, a massive spill dumped more than 2.5 million gallons of raw waste into Hogtown Creek, prompting the Florida Department of Environmental Protection to penalize the publicly owned utility.
Since then, interest in studying the sources of fecal coliforms has remained high. The Alachua County Environmental Protection Department has launched a series of studies to trace the sources of bacteria in Sweetwater Branch and Tumblin' Creek. Faulty GRU collection lines, waste from animals and people and stormwater runoff are all believed to be contributing to the unhealthy levels of fecal coliforms, the county agency suspects.
Hallbourg said despite the progress, however, questions remain.
"Under base flow," or normal water conditions, she said, "it's a little harder to sort out where it's coming from. Homeless people? Failing septic tanks? Leaching sewer lines? Connections to homes?
"There's just a number of things."
For now, the fecal problem appears in check. While historic data suggests an upward trend in pollution levels, Hallbourg said last year's hurricane season helped dilute the fecal bacteria in many urban waterways.
"In most cases, they are still lower than they were prior to the storms," Hallbourg said. "We're kind of waiting to see how things change this year, and see what happens this summer."
In the meantime, additional studies are under way.
As part of the consent order negotiated with DEP following the 2003 spill, GRU's $300,000 investigation will use chemical analysis to genetically match the fecal waste to its sources.
"The goal of the study is essential to knowing the relative contribution of the sources of fecal bacteria in the creeks," said Brett Goodman, a GRU senior environmental engineer.
When the work is completed this fall, he said, "we will know the contribution of humans, wildlife and domestic animals."
The county's environmental health department also is planning a $20,000 study aimed at measuring the impact of septic systems on city creek water quality. Paul Myers, director of the county's Environmental Health Section, said that study should be completed by June.
"The question that we wanted to answer: What contribution, if any, do septic tanks have on the fecal-loading on Gainesville creeks?" Myers said.
"This is an answer that this community deserves."
Much of the recent push for new information is the result of regulatory changes in Tallahassee.
Under Florida's Total Maximum Daily Load program - which sets limits for the level of numerous pollutants a water body can absorb - fecal coliforms must be cleaned by the party that put them there. In Gainesville, Hogtown Creek, Tumblin' Creek and Sweetwater Branch are all listed by the state as impaired for coliforms, along with nutrients and other contaminants.
Despite the state mandate, however, Myers said his office isn't looking to point blame. Before decisions can be made about how to deal with septic tank or sewer line owners, the extent of the problem must be determined. Only then will efforts be made to pay for what could be costly cleanups.
But there's also a more fundamental reason to get to the root of the problem, as anyone who has ever searched for shark's teeth or volunteered in a stream cleanup can understand.
"The creeks in our urban environment are a resource to this community, and we shouldn't have to limit access" because of unhealthy levels of human waste, Goodman said.
Greg C. Bruno can be reached at (352) 374-5026.

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