Mon River Solids are a Threat to Machinery, but Not Health

Pittsburgh Post-Gazette
17 November 2008
By Don Hopey,

State Department of Environmental Protection tests show levels of microscopic contaminants are high again in a low-flowing, 70-mile stretch of the Monongahela River that serves as the water source for 350,000 people.

Although most of the customers of the 11 public water suppliers drawing water from the river will notice only the "hard water" problem when they see the spots and cloudy residue on glassware emerging from their dishwashers, industry and utility companies are experiencing significantly higher water treatment costs.

The DEP said it has received several reports from industries about equipment problems caused by the contaminant levels. And Allegheny Energy Supply Co.'s 1,710-megawatt Hatfield Ferry coal-fired power plant in Greene County has spent more than $200,000 to filter out the contaminants before they can damage steam boilers and turbines used to produce electricity.

"We've had increased treatment costs because we need very clean water for our power generation facilities," said Doug Colafella, an Allegheny Energy spokesman. "The river water can corrode our systems if it's carrying impurities."

According to the DEP tests conducted last week, the high levels of total dissolved solids, or TDS, originally reported on Oct. 10 by U.S. Steel and other industries with water intakes along the river have returned in the section from the West Virginia-Pennsylvania line north to where the Youghiogheny River joins the flow at McKeesport.

The TDS levels measured in that stretch of the river then and again last week are nearly twice the 500 milligram per liter limit established by state and federal environmental agencies to ensure that drinking water doesn't smell or taste bad.

TDS is a measure of the microscopic organic and inorganic particles suspended in the water. Those dissolved solids in the Monongahela River come from agricultural and pesticide runoff, sewage treatment plant discharges, abandoned mine water discharges and discharges from treatment of water used in deep natural gas drilling operations.

A lack of rainfall in the watershed has produced low flows in the river that the DEP said has exacerbated the TDS contamination.

Those levels had declined in the last week of October after more water was released in response to the problem by two Army Corps of Engineers dams on Monongahela River tributaries in West Virginia. But the TDS levels jumped back up again this month when the dam releases were reduced again because of drought conditions.

The DEP has also ordered the treatment facilities to reduce their intake of the "fracing water" from gas well drilling, limiting those intakes to 1 percent of a plant's total volume. Some treatment facilities have been taking in up to 20 percent of their total volume in fracing water.

Water treatment facilities aren't set up to filter out TDS contaminants. Although the high TDS counts aren't a human health concern, they may affect the taste, smell and dishwashing aesthetics of the hard water.

"The spotting is definitely a result of the TDS situation," said Josephine Posti, a spokeswoman for Pennsylvania-American Water Co., which has 86,000 customers in southern Allegheny, Fayette and Washington counties. "We have had a small number of calls from customers experiencing hard water. It doesn't pose a health risk. It's an unfortunate situation, but it's just aesthetic."

In addition to Pennsylvania-American, the public water suppliers affected are Charleroi Municipal Authority, Belle Vernon Municipal Authority, Washington Township Municipal Authority, Newell Municipal Authority, Tri-County Joint Municipal Authority, Southwestern Pennsylvania Water Authority, Carmichaels Municipal Authority, Masontown Water Works, East Dunkard Water Association and Dunkard Valley Joint Municipal Authority.

The DEP has recommended that customers experiencing unpleasant tasting or smelling tap water use bottled water to drink and prepare food.

Don Hopey can be reached at or 412-263-1983. First published on November 17, 2008 at 12:00 am