Kirstin Davis, Communications Manager, No Phone Number Available
Tuesday, March 24, 2026 at 1:16 p.m.
Beneath the walkways, lawns, and amenities of Riverfront Park, an important piece of infrastructure has been quietly doing its job for decades. Recently, city crews identified a problem with an aging sewer pipe that was allowing groundwater to seep into the system. While invisible to park visitors, this issue had a major impact on Spokane’s wastewater system.
The degraded pipe and manhole were originally installed around the time of Expo ’74, when the park and surrounding infrastructure were built. The pipe runs through what used to be a creek bed and subsurface dam backwater area. Groundwater from the River began infiltrating the pipe through cracks and deterioration, estimated to be between 400 and 800 gallons per minute. That extra water was being carried through the sewer system and sent to the Riverside Park Water Reclamation Facility for treatment.
Although the seeping water itself is not sewer water, it still requires processing once it enters the sewer system. As a result, millions of gallons of clean groundwater were unnecessarily using valuable treatment capacity every day. This fix reduces wastewater processing by up to 1 million gallons per day, improving efficiency and freeing up capacity at the reclamation facility.
The solution was a rehabilitation technique called slip-lining, a trenchless method used to repair underground pipes with minimal excavation. Instead of digging up the pipe, crews pull in a new, stronger pipe with a slightly smaller diameter inside the existing pipe. Specialized concrete grout was pumped between the old and new pipe to block the infiltrating groundwater. The work took one work week and required a detour inside Riverfront Park.
What about the beet juice?
Beet juice is a popular way to counterbalance tractor tires for traction because it weighs approximately 13 pounds per gallon, and water weighs about 8 pounds per gallon. A large portion of the sewer system functions with gravity in this situation, and in order to keep the new pipe from floating to the top, about 300 gallons of beet juice was poured into the new pipe to help weigh it down. This gave the crew the ability to grout and seal the space, restoring the structural integrity and preventing the groundwater from the River from entering the sewer system.
Finally, once the pipe was repaired, a nearby stream saw an increase in water flow, which is great for the Park’s conservation area.
Thank you for your patience if you were rerouted through the park. Your detour led to good things.
In Spokane
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