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Wastewater Treatment

The Budd Inlet Treatment Plant has been providing high-level wastewater treatment for over three decades. It is one of the only plants along Puget Sound to remove nutrients (nitrogen) as part of the treatment process.

Cleaning and Disinfecting Wastewater

Wastewater contains many pollutants and must be cleaned before the water is released back to the environment. The Budd Inlet Treatment Plant provides advanced secondary treatment that includes nutrient removal to help protect water quality in Budd Inlet, where the treated water is discharged. Through the treatment process, LOTT also produces renewable resources for beneficial reuse, including reclaimed water.

Meeting Strict Environmental Standards

Wastewater treatment and reclaimed water production are highly regulated to ensure protection of public health and the environment. LOTT strives to operate its facilities in full compliance with regulatory permits, and has an excellent track record of permit compliance. More often than not, the water is treated to a higher quality than required by permit.

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Treatment Steps

At the Budd Inlet Treatment Plant, both physical and biological processes are used to clean wastewater as it moves through a series of cleaning stages.

For more information about these processes, view the Budd Inlet Treatment Plant Guide (PDF)

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First, a mechanical screening process removes large materials such as sticks, rocks, rags, wipes, toys, trash, and other debris.

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Primary Treatment

Solid material gets removed from the wastewater as it floats to the surface or sinks to the bottom of large tanks. “Floaters and sinkers” are removed and processed in solids handling.

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Secondary Treatment

Bacteria naturally present in the wastewater consume and break down additional pollutants. The biological process is carefully managed to remove nitrogen from the wastewater. This helps to protect water quality in Budd Inlet.

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Secondary Clarification

The water rests in these basins so that bacteria and other suspended solids will clump together and settle out of the water. The bacteria are collected and some are sent back into the treatment process to be reused.

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The final treatment step is disinfection with ultraviolet light, which makes any remaining pathogens sterile.

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The cleaned water is discharged into Budd Inlet through an outfall off the north end of the Port peninsula.

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Renewable Resources

Creating Resources from Wastewater

As part of its commitment to environmental stewardship, LOTT captures and reuses renewable resources from the wastewater treatment process. Through resource recovery, LOTT is able to reduce its carbon footprint and help our community partners meet their resource needs.

System-Wide Planning

A Long-Term Plan for LOTT's Main Treatment Plant

The Budd Inlet Treatment Plant represents the largest investment in regional infrastructure in our local communities. To protect this community investment, work is continually underway to plan for and implement projects to sustain and improve the facility. In 2006, LOTT developed a plan to identify necessary capital improvements at the plant. Those projects are now complete, including three major upgrades: the Primary Sedimentation Basins project in 2012, UV Disinfection System upgrade in 2015, and the Biological Process Improvements project in 2023. The next generation of upgrades and expansions has been identified in the 2050 LOTT System Plan. These future capital projects will sustain the plant well into the future.

Regulatory Permits

Meeting Strict Permit Requirements

The Budd Inlet Treatment Plant is regulated under a National Pollutant Discharge Elimination System (NPDES) Permit, issued by the Washington State Department of Ecology, under the authority of the U.S. Environmental Protection Agency. Permits are generally issued for a period of five years. The Budd Inlet Treatment Plant permit includes strict nutrient removal requirements and reclaimed water requirements. It also places limits on Combined Sewer Overflows (CSOs) – discharges of untreated wastewater to Budd Inlet. LOTT has had only two CSOs since 1991, and both were due to severe rainstorms. Spills that occur due to blockages in the partner cities’ sewer collection systems must also be reported under the permit, although these spills are outside of LOTT’s control. The Department of Ecology issues a separate permit for the Martin Way Reclaimed Water Plant. LOTT has an excellent track record of permit compliance.