To enhance the performance and long‑term sustainability of Oklahoma City’s drinking water system, STV partnered with the City to modernize lime‑sludge handling at the Hefner Water Treatment Plant. For decades, the plant relied on a lagoon‑based system with a capacity of 100 million gallons per day (MGD) – an approach that had become increasingly costly, landlocked and operationally inefficient. STV provided preliminary design, final design and construction‑phase services for a new belt filter press mechanical dewatering system, creating a more efficient, environmentally responsible solution for solids management at one of the region’s most important potable water facilities.
What challenges did STV address?
The City needed a cost‑effective, space‑efficient alternative to its aging lagoon system, which suffered from high maintenance costs, limited expansion potential and operational reliability issues. The new system had to accommodate future population growth, treat increased flow volumes and stay within a tight implementation schedule while minimizing disruptions to ongoing water production.
What solutions did STV deliver?
STV evaluated multiple dewatering options and identified mechanical dewatering with belt filter presses as the most technically and financially viable solution. The selected system reduces the City’s 30‑year net present value costs by approximately $20 million, increasing processing capacity to 150 MGD, with future expandability to 200 MGD. STV’s accelerated design and construction approach enabled the City to upgrade its solids‑handling system quickly, making this project the largest lime‑solids dewatering installation in Oklahoma.
How does this project benefit the region?
The new dewatering system strengthens Oklahoma City’s ability to provide clean, reliable drinking water while reducing long‑term operational and maintenance costs. Improved solids handling enhances environmental sustainability and ensures the plant can continue meeting the needs of a growing population.
Key stats and accolades
- $20 million in long‑term cost savings
- 150 MGD treatment capacity, expandable to 200 MGD
- Largest lime‑solids dewatering installation in Oklahoma
- Accelerated delivery to support uninterrupted drinking water service
