RTW >Engineering Services > City of Durango
City of Durango Water Treatment Plant Improvements
Tetra Tech RTW evaluated the existing 14-mgd plant that for the need to improve a variety of systems. Specific study areas included modifications to the primary coagulant feed system; rapid mixing for chemical addition; improved hydraulics for sedimentation; and filter upgrades involving media replacement; use of air/water backwash vs. surface wash; underdrain rehabilitation; and backwash pump replacement. Tetra Tech RTW, after recommendations were prioritized, designed a new backwash pumping facility that included a new MCC and flow control instrumentation.
Tetra Tech RTW performed a plant-wide electrical and control system study and prepared a masterplan for the control system upgrade. Tetra Tech RTW then designed the new PLC- and computer-based control system, which included replacement of valves, valve operators, and pneumatic controllers with electronic controllers.
Tetra Tech RTW also conducted an independent value engineering review of proposed pump station and pipeline improvements. Proposed facilities were about 70% complete and comprised 17,000 feet of 30" pipeline and a 9,000-gpm capacity pump station. Ultimately 12 ideas were generated that would save $811,000 in project costs and $869,000 in present-worth costs.