Washington state is home to 142 state parks managed by the Washington State Parks and Recreation Commission (Commission) that encompass approximately 120,000 acres of land. Washington’s parks showcase the natural beauty of the Northwest, and many of them are located along the waterways of the Puget Sound.
The intersection of the state’s Puget Sound conservation efforts and Commission’s mission statement resulted in an allocation of funds to improve the storm water and wastewater treatment systems in 26 state parks that are located on Puget Sound. Ft. Flagler State Park was one of the parks identified for a complete wastewater treatment plant installation to replace its aging septic tank/drainfield systems.Because water quality was a high priority, the Commission selected membrane bioreactor (MBR) technology for wastewater treatment. This technology enabled the 784-acre park to produce Class A reclaimed water for future uses and reduce the amount of nitrogen discharged to Puget Sound. Key project challenges included: locating the treatment plant to avoid environmental and historic area impacts; integrating the operation building’s architecture to match the historic district; designing the facility to minimize any interference with the public’s park experience; automating the wastewater treatment plant and parkwide pump stations to allow for remote monitoring and operation; and the processing high-strength wastewater from recreational vehicles. To achieve these goals, a 25,000-gal-per-day MBR facility was constructed adjacent to the decommissioned sewage lagoons. The design team was able to reuse the lower lagoon for storing the waste activated sludge, which resulted in a significant operational cost savings to the park. The upper lagoon was used as the effluent discharge point where the flows combined with a perennial stream. This allowed the Commission the option of using the lagoon as a storage facility for future water reuse. In addition to the new wastewater treatment plant, a parkwide sewage collection system was constructed to serve the campground areas, RV dump and historic district buildings. Other upgrades associated with this project included the replacement of the park’s antiquated single-phase and three-phase power services, the campground water distribution system and a new telemetry system for remote monitoring of the MBR facility and eight pump stations serving the park