Sanitary Sewer Evaluation

Client—Port of Kalama, Washington

Gibbs & Olson evaluated the Port’s existing sanitary sewer system to recommend if the Port should continue to own and operate a wastewater treatment plant or if the Port should become a City of Kalama sewer customer. The evaluation included the Port’s existing lift stations, conveyance system and package extended aeration treatment plant. If the Port connects to the City’s sewer system, all of the domestic wastewater from within the Port’s current service area will be discharged to the City’s system.

The evaluation considered all the domestic wastewater flows from the Port’s existing customers as well as anticipated flows from proposed development within the north Port area. The City of Kalama’s sewer ordinance was reviewed to estimate both the initial connection cost and the estimated monthly sewer charge if the Port connects to the City’s system. The report summarized the evaluation and presented planning opinions of cost to replace the Port’s existing wastewater treatment plant. It also included costs for design and construction of the infrastructure necessary for the Port to connect to the City’s system. The final report recommended the Port continue to operate the existing plant until it reaches the end of its useful life or until the Port has an opportunity to connect the City’s system associated with a specific project development.