[USA] Raw lake water around the intake mechanisms that draw Toledo’s drinking water from Lake Erie have shown the first signs this year of the dangerous toxin that can cause liver and kidney damage and resulted in a nearly three-day water crisis last August.
Toledo Mayor Paula Hicks-Hudson, speaking during a hastily-called news conference late tonight, said the detection prompted city officials to change Toledo’s water quality status from “clear” to “watch” on a newly developed water-quality dashboard posted on the city of Toledo website.
The mayor emphasized that Toledo’s drinking water remains safe and microcystin has not yet been detected inside the Collins Park Water Treatment Plant.
The intake crib where the toxin was detected is 3 miles out in the lake, the mayor said.
“A very small amount of microcystin was detected in the intake crib … and that is 0.5 parts per billion and below in the raw lake water,” Mayor Hicks-Hudson said. “[That] is equal to about one-half a blade of grass in a football field.”
The mayor said treatment protocols in place are removing the toxin before it can reach the homes of the 500,000 people in Toledo and its suburbs who use the municipal water supply.
“Accelerated treatment is not needed at this time,” she said.
The toxin was first detected at about 2 p.m. at about 0.3 and 0.4 parts per billion. A later sample at 7 p.m. showed the level at 0.5 parts per billion. The mayor made the announcement at 8:50 p.m.
Water takes about 90 minutes to travel from the intake crib to the city’s low service pumping station and then another four hours to travel to the Collins Park Water Treatment Plant. That 5 ½ hours is “more than enough time to treat the water,” Mayor Hicks-Hudson said.
Chuck Campbell, the city’s commissioner of water treatment, said more samples would be taken Tuesday morning.
The city’s water supply was rendered undrinkable Aug. 2-4 last year when the toxin fouled the water at the treatment plant.
Mr. Campbell said some of the new monitoring devices helped the city make the detection today much earlier than it could have last year. The city now has three water-quality-monitoring sondes — one on a floating Lake Erie buoy, one placed inside the water-intake crib, and one at the city’s low service pumping station. The devices give advance warning of water conditions and allow the city to adjust chemical treatment.
Exactly what level of microcystin is harmful is debatable.
The U.S. EPA in May said it is OK for the greatest segment of America’s population — those school-age and older — to drink tap water with up to 1.6 parts per billion of microcystin in it. That amount is much more flexible than the World Health Organization guideline and the one most states, including Ohio, have been using. The new limit for infants and children younger than 6 years old, pregnant women, nursing mothers, people with liver conditions and those on dialysis, is 0.3 part per billion. Those new guidelines set aside 1998 World Health Organization recommendations of 1.0 parts per billion that states have been using while awaiting U.S. EPA guidance.
The Ohio Environmental Protection Agency ordered the city of Toledo to declare the crisis last summer once the toxin level in tap water went above 1.0 ppb. It was found to be above 1.6 ppb during the ordeal, but not consistently.
The city’s water-quality dashboard rates the water from clear to watch, caution, preschool advisory, and do not drink. The caution stage would mean microcystin has been detected in tap water but the level does not mandate a advisory.
Mr. Campbell acknowledged that a massive algal bloom has been detected by the Lake Erie islands and nearby mainland areas, but said there’s no threat yet to Toledo’s drinking water. the growing algal bloom now envelops the waters around the Lake Erie Islands and south toward Port Clinton and Catawba Island, but from there spreads east, not west toward Maumee Bay.
NASA satellite images published online by the National Oceanic and Atmospheric Administration show a thick algal bloom anchored across the middle of Lake Erie’s western basin between Toledo and Sandusky.
Blooms typically start in the most western part of the lake, near Toledo and Monroe, and move eastward. But the formation of algae and the progression of it is not as predictable as some might think: It can shift within hours based on wind direction, wave action, and other factors.
Kelly Frey, superintendent of the Port Clinton water-treatment system, said the current bloom has “been parked right over Port Clinton and Catawba Island” for days.
“It’s been concerning, that’s for sure,” Mr. Frey said. “We’re going to be in for a pretty interesting August and September.”
Raw lake water near the Port Clinton intake had 0.55 ppb on Friday, rising to 1.7 ppb today, Mr. Frey said.
But those concentrations are mostly anecdotal. He said his treatment plant is capable of handling microcystin at many times those levels.
NOAA is expected to publish its weekly harmful algal bloom, or HAB bulletin, soon. In its bulletin published last week, the federal agency noted particularly high concentrations near Kelleys Island.
NOAA said calm weather of recent days is helps algae form, especially during the daytime. Pets should be kept out of the water, NOAA said.
Photo: Mayor Paula Hicks-Hudson updates the current status of Toledo’s water to a “Watch” during a press conference tonight at One Government Center. THE BLADE/JULIA NAGY
View original article at: Microcystin detected in raw Lake Erie water, Toledo water deemed safe to drink