Pipe projects Honored by STI/SPFA

Three six-ton pump-station fittings fabricated for the Gulf Coast Water Authority (GCWA) have been honored by STI/SPFA as the national Pipe Fabrication Project of the Year for 2007. The custom products were fabricated from a 78- by 144-inch concentric reducing bend – cut into five pieces by Hanson Pressure Pipe.

A 5,900-foot pipeline linking two reservoirs of the San Diego County Water Authority was honored by STI/SPFA as the national Pipeline Project of the Year for 2007.

The Gulf Coast Water Authority is working to stabilize the Juliff Pump Station, southwest of Houston. The project involves installation of fittings on a section of pipe drawing water from the Brazos River in Fort Bend County, Texas.

The Juliff Pump Station stabilization project required use of a strong pipe material able to withstand tons of pressure. The Hanson pipe fittings will be placed on the intake side of the pump station to divert raw water from the Brazos River into the canal system for industrial and irrigation purposes.

The pipe bends were custom made by using a reducer to make an 88-degree bend. Typically, specifications will allow for a reducer and a bend, but due to minimal space, Hanson made the reducer and bend as one piece. Each 12-foot tall piece weighs approximately 12,000 pounds and is mortar lined and polyurethane coated.

The reducers’ 144-inch ends provide the water authority – based in Texas City, TX, – with intake screens designed with 5/8-inch diagonal bars and stiffeners.

Fabrication also included mortar linings and green polyurethane coatings.

A project of this size typically takes 9 to 10 months but was placed on hold due to a rainy 2007 and the high elevation of the Brazos River. The Brazos River, usually at an elevation of 12 feet, was hitting numbers in the upper 50s. Construction is expected to begin soon. PBS&J of Austin, TX, is the consulting engineer and MB Western Industrial of Pasadena, TX, is the contracting company for the project.

The Lake Hodges to Olivenhain pipeline project in Southern California, completed in July 2007, was part of a 40-megawatt pumped storage project that used a tunnel to connect two reservoirs that facilitate emergency water storage in San Diego County.

Portions of the welded tunnel liner – featuring steel-plate thicknesses ranging from one-half inch to 1.125 inches – were installed at grades of almost 20 percent. For perspective, an average 20-percent grade would be found on the most difficult mountain-biking trails.

The effort was the first water-supply project in which the steel plate used for pipe fabrication was manufactured using a thermo-mechanically controlled process (TMCP) that complies with the ASTM International standard ASTM A841.

Ameron International of Rancho Cucamonga, CA, fabricated the pipeline with a 10-foot diameter that was capable of handling extraordinarily high water pressure – up to 500 psi. Ameron also provided technical support to the Kiewit/Parsons design/build team during the design and installation of the pipeline. The epoxy-lined project used a straight-seam process – featuring butt-welding from the pipe interior, and incorporating back-up bars. The annular space between the pipeline and tunnel was grouted.

The two projects “demonstrate the strength and flexibility of steel as a material that can provide valuable, long-lasting custom-built solutions for the water industry,” said Wayne Geyer, executive vice president of STI/SPFA.