Critics ask why state failed to warn about toxic algaeBy Perry Beeman
September 26, 2008; DesMoinesRegister.com
An outbreak of toxic blue-green algae that threatened the health of Black Hawk Lake swimmers and Des Moines’ drinking water 150 miles downstream drew little action from state environmental investigators, critics charged this week.
The algae, or cyanobacteria, can cause rashes, intestinal illnesses, even death. Levels in the west-central Iowa lake near Lake View, recorded just after the Labor Day weekend, were seven times more than an internationally recognized benchmark for safe swimming.
State law charges the Iowa Department of Natural Resources with monitoring water quality and protecting Iowans from such outbreaks. Yet no one from the agency warned swimmers to stay out of the 925-acre Sac County lake, which has several beaches and campgrounds.
DNR officials said that no one asked them to investigate, and that they thought Des Moines Water Works had monitoring under control.
But the DNR’s lack of intervention caused water plant workers and farm groups to look themselves for the source of the problem.
At one point, the outbreak – which surfaced in early August and continues this week – forced the waterworks to stop using water from the Raccoon River. The river receives water from Black Hawk Lake when the lake tops an outlet.
A waterworks lab supervisor and representatives of farm and environmental groups say the DNR has been lax in its response to the outbreak.
"A half a million people have a right to expect that the water coming through their city is in some reasonable condition," lab supervisor Christopher Jones wrote in a Sept. 5 e-mail to state water quality officials and Iowa State University scientists. "Who’s accountable for that? … I want it better now, and I want some accountability."
The resources department left others to trace what Randy Beavers, interim general manager of Des Moines Water Works, called some of the Raccoon’s highest blue-green algae levels in three decades. Beavers declined to comment on the DNR’s response.
In August, the Iowa Soybean Association and Agriculture’s Clean Water Alliance, a pair of farm organizations, stepped in to help the waterworks trace the source.
"It became quite obvious" the algae were from Black Hawk, said Roger Wolf of the Iowa Soybean Association.
Less obvious was why the DNR didn’t act immediately to help assess the situation, Wolf said.
"We had uncovered a problem at that point," he said. "We expect the agency to engage."
DNR spokesman Kevin Baskins said the department measures one toxin that the cyanobacteria emit, microcystin, more than most states do. The DNR and the Iowa Department of Public Health also won a federal grant to study cyanobacteria blooms and related health risks at major recreational lakes over the next five years.
Iowa has no official standard to measure other toxins in the algae, in part because it’s hard to predict under what conditions they present a health risk, said Mary Skopec, DNR water monitoring coordinator.
The algae emit toxins only under certain conditions, and even then they don’t do it continuously. Cyanobacteria tend to form smelly scum when toxins are emitted.
Eric O’Brien of the DNR’s water quality monitoring staff said that in the DNR’s defense, microcystin levels this summer in Black Hawk Lake – and all other major Iowa lakes – were well under the informal benchmark the state uses to judge swimming waters.
The American Water Works Association suggests water plants look for a new water source if cyanobacteria cell counts top 15,000 per milliliter, though Des Moines officials suggest that water with more than 10,000 cells per milliliter can taste and smell bad. Typically, the counts in both the Des Moines and Raccoon rivers are under 1,000 cells per milliliter.
This week, the Raccoon readings were 5,000 and 10,000 – still high, but low enough to run into taps. The waterworks has been alternating between the rivers the past week.
Cyanobacteria cell counts in the Raccoon topped 30,000 at the waterworks on Aug. 11.
Skopec said Iowa State researchers hired by the DNR to come up with a plan to restore Black Hawk Lake found levels of microcystin last summer that were less than half the health guideline. No one, she said, asked the department to investigate further.
Skopec also said her department didn’t do extra testing to find the source because it appeared the waterworks was monitoring.
Skopec contended there may not be enough evidence to tie Des Moines’ problems directly to Black Hawk Lake.
However, John Downing, an ISU scientist studying the lake on behalf of the DNR, said data seemed to tie the Raccoon’s problems to Black Hawk. The lake ranked fifth-worst among 162 lakes for public health risks in a five-year ISU study that began in 2000.
Susan Heathcote, who serves on a state commission overseeing the DNR and follows water quality issues for the nonprofit Iowa Environmental Council, said the department should have shown more interest in a problem that has become more common across Iowa.
"It’s kind of don’t ask, don’t tell," Heathcote said. "We know there are issues, but we aren’t being proactive to warn the public. You need to investigate why it was occurring. It should have been an urgent issue."