Asbestos in Water
Posted 11/29/10, by Skagit PUD
Skagit PUD recently had a large water main break in West Mount Vernon that released about 1.5 million gallons of water into the surrounding neighborhood. The pipe that broke was made of asbestos-cement and installed in 1969.
Safety
We recognize that when people hear the word asbestos it can raise concerns.
Asbestos-cement pipes are made from cement with asbestos fibers added to make the pipes strong. Most drinking water passes through these pipes without becoming contaminated with asbestos fibers, and so they are safe.
The use of asbestos-cement pipes dates back to the early 1900s and is used in virtually every country in the world. The use of asbestos-cement pipes increased following World War II, when iron and steel was diverted to the war effort.
Although asbestos has been banned for many uses by the US government because of health risks caused by breathing asbestos fibers, asbestos-cement pipes are exempted. Cement-lined iron pipe is the most common pipe used these days.
Skagit PUD maintains 600 miles of pipelines within the county, with approximately 25 percent of our distribution system consisting of asbestos-cement pipe.
A few types of drinking water—water that is slightly acid or contains few minerals—tend to dissolve the cement in asbestos-cement pipes, softening the pipe and releasing fibers into the water. However, Skagit PUD’s water is low in acidity.
Because of the US Environmental Protection Agency’s (USEPA) lead and copper regulation, water quality must be adjusted to make sure that the water is not corrosive, thus helping prevent fiber release. If the pipe stays solid, the fibers are so tightly bound in the pipe material that they will not be released and the pipe is safe.
Research has found that the greatest risk with asbestos comes from inhaling the fibers, not from ingesting it. Cutting into an asbestos-cement pipe could release asbestos fibers into the air. Skagit PUD crews are trained and have safety gear while working with asbestos-cement pipes.
Skagit PUD has a pipe replacement program that addresses aging pipes in our distribution system. The program calls for replacing one percent of our total pipe in the ground per year.
Source: American Water Works Association