Interceptor Master Planning Produces a Phased Program

Constructed in the early 1970’s, the Walker-Calloway Branch Outfall Trunk Sewer System (W-C) is owned and maintained by the Trinity River Authority (TRA). Flows discharge into the 96-inch City of Fort Worth Village Creek outfall where collapses, surcharging, and backups were recurring. This multi-phase program began with a condition and capacity assessment to understand current conditions, the remaining useful life (RUL) of the pipe, risks of failure, and project future capacity needs for the 2040 planning horizon.

The W-C improvement program structured recommended repairs into seven phases. The Preliminary Design Report (PDR) identified that approximately 90% of the system required rehabilitation, with the majority of work recommended to be rehabilitated by trenchless methods. 

• The multi-sensor pipe inspections estimated that 48% of the interceptor had an RUL of less than two years. This was a critical factor for prioritizing repairs.
• Three sections of the interceptor are being upsized due to a low point at a creek crossing. CIPP rehabilitation was selected as the best repair method for the remaining sections.
• Erosion issues for a 42-inch segment of the pipe was exposed at a creek crossing and required channel stabilization measures.
• Phase 1 design involved re-routing 4,463 LF of 42-inch pipe and rehabilitating the meter station. Mag meters were installed to measure flows at the meter station.
• CIPP is being used to improve the Phase 2 and 3 (6,454 LF of 27- to 42-inch pipe) sections and requires extensive bypass pumping (7,000 LF).