NOT YOUR AVERAGE WALLPAPER – REHABILITATION OF THE WOOD STREET INTERCEPTOR

The Wood Street Interceptor project involved the rehabilitation of 3,000 feet of 105-inch diameter reinforced concrete sewer pipeline that was 50 years old and gradually deteriorating due to hydrogen sulfide corrosion. East Bay Municipal Utility District (District) has completed two rehabilitation projects in the Wood Street Interceptor using the Danby and Linabond processes to install corrosion resistant PVC liners. By installing corrosion resistant liners, the useful life of the pipeline has been extended by another 50 to 100 years.The Danby rehabilitation method involves installing PVC forms over the pipe interior surface and placing cementitous grout behind the forms in several lifts over several days.The Linabond rehabilitation method involves spraying of a high strength thermosetting resin to the surface of the concrete pipe. The resin expands in an exothermic reaction to form a section of rigid cellular plastic which firmly bonds with the concrete. A thin flexible PVC liner was then placed over the resin.The construction effort was remarkable for its efficiency and high level of coordination under hazardous confined space conditions. Because the interceptor remained active, work had to be performed during a 6-hour window at night when flows were at their lowest. Rigorous safety measures were required to ensure the safety of personnel in the pipeline. Close coordination was required with operations staff at the downstream treatment plant influent pump station to ensure that interceptor levels were maintained low enough for work to occur. As a result of the excellent coordination effort, the project was completed with an excellent safety record, no lost construction days and no community complaints and zero change order.