A Sept. 25 Chicago Tribune article warned of elevated lead levels in drinking water resulting from water main replacement and water meter installation. Lead levels do increase after disruption of the water service pipe during underground construction. But there is a simple solution: Flushing water through the pipeline removes any lead particulates that may have come loose during construction. This can be accomplished by opening all spigots in the home and letting the water flow for three to five minutes.
In Evanston, the vast majority of the water services (the pipeline that carries the water from the water main in the street to the water meter in the home) are constructed of lead pipe. Evanston has been adding a blended ortho/poly phosphate to the drinking water since 1992 to form a thin coating on the interior of the water service line that mitigates the water from coming in contact with the lead.
When a new water main is installed, the City replaces the portion of the water service between the water main and the shut-off valve in the parkway with a new copper pipe. The new copper pipe is then reconnected to the existing water service (for which the property owner is responsible) between the shut-off valve and the water meter. This work can loosen sediment and particles and disturb the blended phosphate coating.
It is a good practice to flush water through the water service any time that there has not been water usage for more than six hours – for instance overnight, or during the day when parents are at work or children are at school.
Most water services in Evanston are 1-inch in diameter and approximately 100 feet long. Flushing five gallons of water through the pipeline will remove all the water in the lead pipe water service line and begin drawing fresh water from the water main. Flushing the toilet and running water to wash hands will require about two gallons of water. Taking a shower will flush the entire water service line.
There is no detectable lead in the water that is provided to the Evanston community. Lead in drinking water comes primarily from materials and components associated with water service lines and home plumbing. The City of Evanston is committed to providing as much educational information as possible to assist residents in reducing exposure to lead in their drinking water. Additional information is available from the Utilities Department at 311, or 847-448-4311, at www.cityofevanston.org and at the USEPA website, http://water.epa.gov/drink/contaminants/basicinformation/lead.cfm.