CONSTRUCTION
White Tanks raw water basin to 33 MGD as part of this project , he explains . “ In recent years our peak demand in the summer has been pushing 19 MGD . The capacity was stressed so we had to expand .”
A further challenge was that a number of events , including heavy rain events and storm runoff in the summer , can result in a surge of particles and mud to the CAP , which disrupts the plant ’ s treatment ability because of the time it takes for this turbidity to settle out . When these water quality ‘ excursions ’ happen , they can last for up to three weeks . Excursions don ’ t happen every year , but Brown and his team looked for a way to solve this problem at the same time as expanding the overall capacity of the plant . “ We did something unique !” he says . “ Besides taking the White Tanks Regional Treatment Facility from 20 to 33 MGD we knew we needed more enhanced treatment technology to address the excursion events and build resiliency in the treatment process .”
The solution ultimately chosen was ‘ ballasted flocculation ’, which will provide more efficient and effective removal of particulate matter from the water . Conventional flocculation / sedimentation methods were dismissed due to both size and cost constraints . The ballasted flocculation system chosen for the White Tanks was a CoMag system from
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