Cleveland Water Department pursuing $2M fix for discolored water caused by algae in Lake Erie

Decomposing algae at the bottom of Lake Erie has led to recurring problems with discolored, manganese-tainted water reaching the taps of some Cleveland Water Department customers – an issue the department is now looking to remedy with a $2 million project.

The work involves upgrades to the intake crib in Lake Erie that feeds water into the Nottingham Water Treatment Plant, which supplies water to Cleveland’s East Side and several eastern suburbs.

That intake crib – located near the lake bottom, about three-and-a-half miles offshore – is the most susceptible of the Water Department’s four cribs to hypoxic water, which ultimately results in yellow- or brown-tinted water flowing out of taps, Director of Public Utilities Martin Keane told a Council committee on Tuesday.

The phenomenon usually occurs in late August or early September along the lake bottom, where algae settles. As the algae decomposes, it consumes much of the oxygen available, resulting in hypoxic – or low-oxygen — water. Lack of oxygen causes the water’s pH to drop, allowing it to absorb metals from the bottom of the lake, including some iron and manganese, which causes the discoloration, Cleveland Water Commissioner Alex Margevicius said.

To avoid pulling in such water in the future, the Department plans to raise its crib farther off the lake floor – from 10 feet currently, up to 18 feet once the project is complete. It will entail placing an eight-foot-tall, 75-foot-wide ring, likely made of steel, on top of the existing structure.

Officials believe that the water captured at that higher elevation will be far enough from the lake bottom to avoid the issue. Buoys that monitor water quality have indicated the eight-foot boost will be sufficient, Margevicius said.

Construction is expected to happen next year.

While Margevicius described hypoxic water as an “aesthetic” problem, Councilman Mike Polensek said it routinely raises concerns from residents who fear their drinking water is unsafe.

It’s a growing issue, largely due to an increase in algal blooms in the lake’s western basin that eventually drift east and affect Cleveland’s water supply, Margevicius said.

Hypoxic water has led to tinted tap water on the East Side during three of the last four years. The most recent incident occurred last September, when some customers, from Euclid to Hunting Valley, experienced discolored water for five or so days. At the time, officials said the water was safe to drink, though they noted it could have a slight metallic bitter taste, and could stain laundry.