• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Baffling Water Pipe Leaks End in Brown Deer: Adding Chlorine Helped; Milwaukee's Possible Role Unproven

Posted on: Monday, 12 June 2006, 03:00 CDT

By Marie Rohde, Milwaukee Journal Sentinel

Jun. 12--Brown Deer -- The slimy green stuff that was eating away at copper water pipes in the village has been defeated, but what caused the problem remains unclear.

The village appears to have ended a mysterious increase since the late 1990s in the loss of water it was buying from the Milwaukee Water Works and selling to private homes and businesses in the community.

Even more perplexing had been the large number of copper pipes on private property that were springing leaks.

The unexplained water loss -- the difference between what the village bought from the Milwaukee Water Works and what it sold to residents and businesses -- had jumped from 3.4% to 9.4% between 1998 and 2002, village officials said. Martin Glodoski, then the superintendent of the village's water department, sent workers door to door looking for leaking pipes. While he didn't expect many to be found -- only two had been found between 1986 and 1997 -- workers found 31.

Costly problem

Fixing the leaky pipes cost property owners thousands of dollars, and the loss of water meant the village was paying almost 10% more than it should have, so the village hired Abigail Cantor, a Madison chemical engineer, to investigate the problem.

Cantor's conclusions were controversial: She said the decision by the Milwaukee Water Works to switch to ozonation to disinfect Lake Michigan water before distributing it to customers caused the problem.

Marc Edwards, a leading national water expert hired by Milwaukee, disagreed. He concluded that the problems with the copper pipes were caused by poor design and installation practices.

Increasing chlorine

Theera Ratarasarn, a drinking water specialist with the state Department of Natural Resources, said a lack of chlorine was causing problems in Brown Deer, but said he could not agree that Milwaukee should increase its dose of chloramine, the disinfectant added at the end of the water treatment process.

"It really worried me," Ratarasarn said. "But no other communities were reporting problems, and so I encouraged Brown Deer to increase its chlorine."Milwaukee began using ozonation as a short-term disinfectant for Lake Michigan water at its plants in 1994.

Chloramine -- a chlorine and ammonia compound -- is added, and at least a trace of the chemical should remain in the water, even at the most distant faucet on the system.

Disinfectant was running out

In Brown Deer, officials said there were areas where no residual of the disinfectant was found and other areas where there was little.

The ozonation breaks up pieces of debris in raw lake water into tiny particles of only two or three molecules. The microscopic pieces of lake weed, dead fish or duck feces are small enough to slip through filters at the plant.

That stuff becomes food for microbes in the water. Most of the microbes are killed by chloramine, but by the time the water reached Brown Deer in the far reaches of the system, the disinfectant was depleted before killing off the microbes.

Figures improve

The bugs seek out areas in pipes where debris accumulates -- eating it, reproducing and secreting an acidic green film.

The film protects the bugs and eats at the copper pipes. Pinholes eventually form in the pipes.

In late 2003, the Village Board agreed to spend $160,000 to construct a building and install equipment that would boost chlorine to the drinking water supply in the village. Michael Rau, the general manager for We Energies Water Services who now serves as the superintendent of Brown Deer's water department, said there has been only one report of a copper pipe leaking since the chlorine booster was added 2 1/2 years ago.

The unexplained water loss dropped from 9.4% to 2%.

"That would seem to support the theory that the microbial corrosion was causing the problem," Rau said. "The best way to control it is with chlorination."

Water hydrants flushed

Carrie Lewis, superintendent of Milwaukee Water Works, said Brown Deer also made other changes, including flushing water hydrants on a regular schedule.

"Maybe it was doing those things that they weren't doing before that solved the problem," Lewis said. "I was never convinced that adding more disinfectant at the plant was the solution."

-----

Copyright (c) 2006, Milwaukee Journal Sentinel

Distributed by Knight Ridder/Tribune Business News.

For reprints, email tmsreprints@permissionsgroup.com, call 800-374-7985 or 847-635-6550, send a fax to 847-635-6968, or write to The Permissions Group Inc., 1247 Milwaukee Ave., Suite 303, Glenview, IL 60025, USA.

Source: The Milwaukee Journal Sentinel

More News in this Category