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How Recent Updates to the Sanitary System Protect Our Community

Epic Rainstorms in 2022 That Would Have Resulted In Sewer Spills in the Past Were Managed by the Updated Sanitary System

During the major rainstorms of December 2022, our community was pummeled by over six inches of rain in one two-day period plus six more inches the rest of the month.

Heavy rainfall seeps into private sewer laterals and other facilities causing flows through pipelines and the treatment plant to shoot up by as much as 900% above normal.

In the past, this would have resulted in sewer overflows, but the upgraded treatment plant managed well with one overflow from a manhole.

New equalization basins are key to success. There were many factors helping manage these storms, but the equalization basins where staff diverted large amounts of sewage that could be held safely and treated over time.

Treatment Plant Manages Through Major Power Outages and Heavy Rainfall in January 2023

Over ten inches of rain pounded our community in the first half of January 2023. The challenge of the resulting high flows was compounded by multiple PGE power outages, including one that lasted over ten hours.

Recent upgrades raised secondary treatment capacity by about 50% and the new equalization basin allowed staff to store some of the high flows and introduce it back into the system later after high flows subsided.

A backup electrical generator being transported by an industrial forklift as a worker watches on.A new backup generator being installed at the treatment plant.

New Backup Generators Made It Possible to Operate Through the PGE Outages

In March 2023, the District completed a $2.2 million project to replace four District-owned backup generators and one owned by the City, along with one aging control panel. The District maintains and operates City pump stations for which the City pays all costs. The new generators were put to the test in January 2023 when PGE power failed repeatedly, and our generators served us well.