Operations are almost back to normal at the Post Point wastewater treatment plant in Bellingham, nearly a week after a broken pipe caused a 3-foot-deep flood in an underground passage of the facility.
A basement of the plant at 200 McKenzie Ave. was flooded with 750,000 gallons of wastewater –enough to overflow an Olympic-size swimming pool – when the 30-inch pipe failed in the plant’s secondary treatment facility around 1:30 a.m. May 6, according to the Bellingham Public Works Department.
About 10 minutes later a worker closed a valve that prevented sewage water from flooding the entire plant. Over the days that followed sewer water was released into Bellingham Bay after going through basic treatment, but not the secondary stage, where bacteria removes pollutants from the water.
By Thursday night workers had installed the first of four 12-inch pipes in a new, temporary bypass system. It could take days for secondary treatment to get up and running to full capacity again, and another four to five months for a more permanent solution, said Eric Johnston, assistant director of Public Works.
In the meantime, Johnston emphasized the wastewater posed no public health risk when it was released into the bay over the past few days: all samples tested below 12 colony-forming units per 100 mL, whereas the rate considered acceptable by the state Department of Ecology is 200 to 400 cfu/100 mL.
Post Point has treated Bellingham’s wastewater since the 1970s. The city added the secondary treatment system in 1993. No workers were hurt when the pipe failed last week.
So far Public Works has no clear answer as to how the pipe broke, and how much repairs will cost. Both of those should become clearer, Johnston said, in the coming days and weeks.