Texas-Sized Interceptor (Source: Civil + Structural Engineer)

Aug 1, 2017

By Paul Banschbach and Kelly Davis

The Trinity River Authority of Texas’ (TRA) Central Regional Wastewater System began operations in December 1959 as the first regional facility of its kind, serving Irving, Grand Prairie, and Farmers Branch, plus a portion of western Dallas. The system has since expanded to serve all or part of 21 contracting parties and approximately 1.2 million people in the Dallas/Fort Worth area.

The Mountain Creek Interceptor System is one of five major interceptor systems that convey flow to the Central Regional Wastewater System treatment plant. The Mountain Creek Interceptor collects wastewater from portions of six contracting parties within the Central system including the City of Grand Prairie where the interceptor is located. The existing MC-7 and MC-8 segments consist of 17,000 linear feet of 48-inch to 60-inch unlined reinforced concrete pipe installed in the 1970s.

In 2004, TRA initiated an assessment of the pipeline condition and capacity for a portion of the Mountain Creek Interceptor including segments MC-7 and MC-8. The assessment determined that the pipeline was in need of replacement due to extensive corrosion and additional capacity needs. Subsequently, TRA retained Lockwood, Andrews & Newnam, Inc. (LAN), a planning, engineering and program management firm, to design improvements for the interceptor and take the project from preliminary design to construction advertisement.