Get Full Government Meeting Transcripts, Videos, & Alerts Forever!
Get email alerts on the Water Quality topic
No spam. Unsubscribe anytime.
District weighs short-term fixes and longer-term plan for summer "brownwater" problem
Summary
Board members and staff discussed a recurring summer brownwater (red-water) problem; a resident suggested polyphosphate dosing as a short-term sequestering fix, but operations staff warned it would not address the root cause (very negative Langelier Saturation Index). District has contracted a root-cause analysis and is pursuing grant funding for a brownwater project.
A public comment submitted by a local water professional suggested the district consider polyphosphate sequestering agents as a lower-cost, short-term way to reduce summer brownwater (red-water) events. The comment was relayed during the meeting and staff responded with technical caution.
"It would be much less expensive to do," the commenter wrote by email, recommending a polyphosphate feed to form a protective film in pipes. Operations staff replied that polyphosphate as a standalone agent "will not be effective against an LSI value of -1 to -2.5," and that the district's root cause is an extremely negative Langelier Saturation Index that requires more comprehensive treatment and design changes. Staff also noted regulatory steps (design submittal and permit modifications) would be required before making in-plant changes.
The board has engaged a firm for a root-cause analysis and funding identification for a brownwater remediation project. In the meantime, operations said it would attempt interim operational changes (maintaining higher reservoir levels, adjusting alkalinity and targeted chemical use) and planned to pull temporary pumps back into service in May to reduce dependence on rentals. Staff said these operating measures increase short-term fuel and operating costs but aimed to limit severe brownwater incidents like those seen last summer.
The board emphasized that grant options are being explored to implement a capital fix. No formal vote was taken on chemical dosing; the board recorded the technical guidance and agreed to proceed with the contracted study and funding-seeking activities.
