Union Electric Co. is working at the William-Sheridan intersection this week to upgrade its gas mains as part of an on-going project to replace cast iron mains along William.

Ralph Maxton, district engineer for Union Electric's gas division, said the outside, eastbound lane of William will be blocked from 500 feet west of Sheridan to just east of Sheridan.

Maxton said Sheridan will be closed to traffic between Good Hope and William while the work is going on. He said work at the intersection should be completed by Monday.

Maxton said UE is installing a section of 10-inch, high-pressure, steel gas main beneath the intersection.

"From the intersection of William and Sheridan, plastic gas main will be extended south on Sheridan to Good Hope," he said. "From there we'll install about 2,670 feet of 10-inch plastic gas main eastward on Good Hope to Louisiana Street, where it will tie in to the existing plastic gas main that was installed over the past two years."

Maxton said it should take about six weeks to run the main from Sheridan to Louisiana. When that section is completed, Maxton said the main will provide an east-west "bridge" between UE's 10-inch, high-pressure gas distribution loop around the city.

"As soon as this east-west gas line is completed, we will abandon, in place, the old cast iron main that runs along the south side of William Street," he said.

"This cast iron main has become brittle over its lifespan, and is subject to frequent cracks due to a number of reasons such as ground subsidence, excavation, and temperature changes. We have had to repair a number of breaks in the old cast iron main the past several years. Because the main is on a busy street, it is difficult to repair without causing problems for motorists."

Maxton said the 10-inch plastic main now extends eastward on Good Hope from Louisiana and ties into another main on Good Hope between Ellis and South Sprigg. From there the new line was built southward to the UE regulator station on Hackberry, then west to the UE peak shaving plant west of Hickory Street.

"After we complete the rest of the Good Hope gas main construction, we'll start work on extending the 10-inch plastic gas main northward from Good Hope out to Bertling, where it will tie in with the existing gas-main distribution line," Maxton said. "This project will take about two years to complete and will be done in several phases. The new gas main will run northward between Sprigg and Ellis."