Test results on tadpoles allowed to swim around in some of Flagstaff's reclaimed wastewater could lead to a metamorphosis of how the city of Flagstaff looks at its water recycling program.
At the Flagstaff Water Commission meeting Thursday, Northern Arizona University professor Catherine Propper and U.S. Geological Survey scientists shared data that shows what trace contaminants are present in the city's reclaimed wastewater and how it could impact the environment. The organic contaminants tested appeared in trace amounts and include antibiotics, tobacco byproducts and aspirin.
More than 20 people attended the afternoon advisory commission meeting, given the controversy over a proposal to use the reclaimed wastewater for snowmaking at Arizona Snowbowl.
Propper told the commission members that she conducted lab studies on aquatic animals to observe how the reusable wastewater the from Rio de Flag plant could impact their endocrine systems.
Experiments on mosquitofish and their male sex hormone activity and testing on bullfrogs' stress systems and behaviors showed few impacts created by the reclaimed wastewater. But when Propper and her student researchers raised African clawed frog tadpoles in the wastewater, they found startling results.
"Here's what I call the bad news," Propper said. "The reclaimed water significantly increased the rate of metamorphosis."
Propper displayed a graphic from her PowerPoint presentation that showed where, from day 36 to day 51 of the study, the tadpoles in the reclaimed wastewater sharply accelerated their growth rate when compared to the two control groups.
Based on that study, Propper explained to the commission that the "reclaimed water contains a substance that either: Acts directly like thyroid hormone or stimulates the release of natural thyroid hormone."
Those results were enough for Propper to recommend continued studies of the city's reclaimed wastewater, groundwater and surface water to learn more, but she noted that it could mean four years of research costing as much as $800,000.
The commission voted unanimously for water department head Ron Doba to meet with Propper and USGS hydrologists to develop options of further study, which would include less pricey options.
And detractors of the Snowbowl plan to pump the reclaimed wastewater to the ski area want the study to date to become part of the environmental impact statement now under revision and review for the snowmaking upgrade.
"The Forest Service needs to take a look at these studies in the EIS," said Andy Bessler, who spoke on behalf of the grassroots activist group Save The Peaks Coalition. "Along with the snowmaking, they plan to have a pond up there, so animals and wildlife will be drinking it."
The coalition has led the opposition against the Snowbowl upgrade because its members contend that snowmaking is a desecration to the San Francisco Peaks, which are viewed as sacred by 13 regional Native American tribes.
Supporters of the Snowbowl plan point to the drought problems and the costs to stay within growing industry standards as reasons to have snowmaking. Without it, the ski area could experience a shutdown.
In recent years, the USGS has started examining organic contaminants such as pharmaceuticals, industrial and household wastes that currently are not under any Environmental Protection Agency guidelines.
As part of this, the Survey partnered with Propper to help the city examine its wastewater effluent, a project initiated this summer.
USGS hydrologist Margot Truini told the commission members that some of these contaminants are considered endocrine disruptors.
The USGS tested reclaimed wastewater from the city's Wildcat water treatment plant; the Rio de Flag's storage tank at Buffalo Park, which stores the reclaimed water from the Rio de Flag plant; and water from one of the city's groundwater source.
Based on the USGS report, lab testing found trace levels — on the scale of parts per billion — of 22 human drugs and household waste products in the water at the Rio de Flag storage tank.
By comparison, the older Wildcat facility had 42 such contaminants, which appeared in greater amounts on average than what was found in the Rio de Flag water. Tests on well water from the Fox Glenn source found four of these contaminants.
Despite notable results on the tadpole experiment, both Propper and Truini indicated to commission members that it's difficult to pinpoint the environmental effects of each contaminant, how much is required to create an impact and how the compounds could interact with one another.
Arizona Department of Environmental Quality spokesman Patrick Gibbons said by phone Thursday that his agency is paying attention to the results of the USGS testing, which is happening across the state.
He said that the endocrine disruptor contaminants are not part of any ADEQ guidelines and noted that the Survey is doing "the cutting edge work."
"We deal with it when the science becomes policy and law," Gibbons said.
Reporter Seth Muller can be reached at 913-8607 or firstname.lastname@example.org.
— Arizona Daily Sun