Abstract
The DuPage Water Commission serves a population of over 700,000, in twenty-three suburbs in DuPage County, Illinois. The distribution system consists of 140 miles of concrete, ductile iron, and steel pipe ranging in size from 90 inch down to 12 inch.
During the initial design of the system it was considered that several environmental factors might be present which had the potential to accelerate corrosion of the pipelines. Road salt percolating into the soil from adjacent roadways might affect the rate of corrosion, particularly of prestressed concrete cylinder pipe. The pipelines might be laid through isolated peat beds, which were known to exist in various areas of the county. Throughout the county there are numerous natural gas and petroleum product transmission pipelines and electric and telephone facilities protected by impressed current cathodic protection systems. Stray current interference was therefore considered likely.
On the basis of these factors it was considered prudent to install measures during the initial construction to permit future monitoring of the corrosion potential of the pipelines and to simplify the implementation of protective measures, should they prove necessary. This paper explores the development of the monitoring system and determinations made from initial testing performed by the contractors.
