Parkland/Brookdale Interceptor Phase 3
About the project
This project is the third of multiple phases necessary to provide increased capacity for the Parkland/Brookdale Interceptor. The existing 36-inch sewer interceptor between phase 2 and the future interceptor phases is expected to reach its capacity by the end of 2024.
To address that capacity need and to build a system that will last well into the future, Pierce County is constructing a 72-inch interceptor that will convey wastewater from the intersection of 131st Street East and A Street South to an existing sewer interceptor at 129th Street South and C Street South.
Future phases of the project will address other capacity issues in the existing system.
What is a sewer interceptor?
A sewer interceptor is a major sewer line that receives wastewater flows from multiple collection lines. These could be main or trunk sewers, or force mains, or other kinds of sewer lines. This combined flow is then directed to a wastewater treatment facility or another interceptor.
What does this mean for me?
This project will increase the capacity of the existing interceptor to handle growth beyond 2024. It also replaces aging infrastructure with materials that are less likely to corrode, and so will last longer in the wastewater environment.
Pierce County will maintain existing sewer connections and make connections to the new interceptor where applicable. Pierce County will maintain service in the area without interruption by bypassing existing sewer flows.
Intermittent road closures will be necessary to complete the work. The contractor will be required to provide advance notice of any closures and maintain local and emergency vehicle access.
Privately owned property in County right-of-way
The contractor will need to make use of the county right-of-way to install the sewer line. Property owners may need to remove privately owned items within the right-of-way that they wish to salvage prior to construction.
Dewatering During a Sewer Construction Project
Measuring and tracking groundwater levels is a standard practice in ensuring a safe and efficient environment for construction projects that require any underground work, including sewer infrastructure projects.
Groundwater is water that collects or flows beneath the Earth’s surface and is a naturally occurring resource in our region.
During a preliminary design phase of a sewer project, Pierce County Planning and Public Works installs groundwater monitoring equipment along the construction area to track the seasonal changes in groundwater levels.
Using this data, we can anticipate seasonal groundwater trends and stay ahead of potential groundwater issues.
If there is a possibility that the excavation for a sewer construction project will reach the groundwater level, the contractor hired by Pierce County is responsible for developing a dewatering plan before construction begins. The dewatering plan varies by the flow and the amount of water they will be dealing with.
The Parkland/Brookdale Interceptor Phase 3 project will begin in summer 2022, when groundwater levels are lowest. The contractor will have two crews working at the site to accelerate the project to limit the need for dewatering efforts.
If crews encounter groundwater, the contractor plans to use mobile pumps to remove the water in the trench. That water will be treated to remove sediments or pollutants, and the water will then be discharged to the C Street storm drainage outfall.
While the contractor is excavating and installing the new sewer pipes, there will not be wastewater discharged from the sewer pipes. No fresh groundwater will be contaminated with wastewater. In an event there is a spill, any contaminated water would be directed to the wastewater treatment plant, and the site will be cleaned up.