UCT - WaterWorks (continued)
WEDNESDAY, JANUARY 25
WATERWORKS CONFERENCE: CAN WE AFFORD IT?
Track Moderator: Gary Oradat, Consultant
9 - 9:25 a.m.
Condition Assessment Of Water Pipelines Using Multiple Inspection Tools
Speaker: Andrew Dettmer, PhD, PE, Senior Project Engineer, Carollo Engineers
A risk and condition assessment case study for 26 miles of large diameter raw water pipelines constructed in 1955 near Salt Lake City, UT, will be presented. In 2010, 15 internal and external inspection technologies were utilized in 2010 to determine the condition of these pipelines.
9:30 - 9:55 a.m.
Completing Arizona’s First Potable CIPP Water Project
Speaker: David Rosenberg, Business Development Manager, Insituform Technologies
A project to repair a 12” concrete-coated and concrete-lined steel water main running underneath an Arizona interstate was completed in 2010. The city of Phoenix’s Water Services Department selected a fully structural fiber-reinforced cured-in-place pipe (CIPP) solution after its main had previously been damaged by a contractor. The section of main ran roughly 250 LF underneath I-17 in the Sweetwater area of Phoenix. The project took just days and was pressure-tested to a rate of 150 psi before being deemed a successful completion. The project was challenging for a variety of reasons, including scheduling needs, short pot life of epoxy resin and the requirement of special safety precautions. Some of the environmental benefits of the project included using less energy, fewer pollutants and less excavation.
10 - 10:25 a.m.
Relocate Two Water Lines Under Galveston Bay – Pilot Tube Microtunnel, Slurry Bore, Directional Drill? What The Heck, We’ll Use All Three
Speaker: John Tompkins, PE, Project Engineer, Boyer Inc.
The Galveston Railroad Causeway Lift Span Bridge Replacement project is being done by the County of Galveston, TX, for the U.S. Coast Guard and BNSF Railroad. The existing bridge across Galveston Bay was built in 1912 and has a 100’ wide Bascule lift over the Intracoastal Waterway. This is being widened to 400’ and replaced with a lift span. The existing 30” and 36” waterlines on the bridge had to be relocated. The construction necessitated building two 30’x70’ cofferdams 50’ deep and two 42’ diameter cofferdams 50’ deep in the salt water subject to tidal currents, high winds, commercial and recreational marine traffic and potential hurricanes. The twin 48” steel casings to carry the new 36” waterlines were installed between the cofferdams using pilot tube microtunnel techniques to construct four 170’ long bores and a combination of directional drilling and slurry boring techniques to construct two 780’ long bores. This challenging project required the innovative use of a combination of methods and some unique equipment and techniques all while maintaining boat and rail traffic.
10:30 - 10:55 a.m.
East St. Louis Treatment Plant Backwash Line Rehab
Speaker: Gary Penrod, Business Development Manager, Insituform Technologies
In early 2010, Illinois American Water needed a cost-efficient solution to replace a leaking backwash force main discharge pipeline at its East St. Louis Water Treatment Plant. The pipe in question runs directly beneath a sensitive wetlands area as well as beneath railroad tracks and a concrete levee before discharging directly into the Mississippi River.
The leak itself was located between two railroad tracks. Conventional repair would have necessitated abandonment of the 2,250’ existing pipe and then rerouting with the installation of a new pipe. This would have required boring a new pipe under the railroad tracks and the levee. Pipe replacement in each of these areas was cost-prohibitive and digging was not a viable option in this environmentally sensitive area. Fiber-reinforced cured-in-place pipe (CIPP) was used to rehabilitate the force main. Numerous challenges included a pressure in the force main that was affected by the water level in the Mississippi River and made it necessary to complete the project while the Mississippi River was at a low stage. Also, a duckbill backflow preventer had to be removed prior to CCTV verification. Finally, nearby power lines complicated site set-up.