San Francisco’s Public Utilities Commission has consistently maintained that the two major storms that sent raw sewage and floodwater spewing into Marina district homes in 2021 and 2022 were the result of massive, unprecedented rainfall — and not the fault of The City’s sewer system.
“I noted that it was quite a coincidence that the Marina had flooded that badly during the very next storm after the Pierce outfall was closed,” said Megan Abadie, a former SFPUC assistant engineer responsible for inspecting The City’s outfalls. “But I wanted to wait until I saw the data to conclude whether the Pierce outfall closure contributed to the damage. Then, I saw the data and modeling. It was quite clear that the Pierce closure contributed to the damage.
Unlike other California coastal cities, San Francisco employs a combined sewer system, which means the same network of pipes collects and treats sewage and stormwater. This two-for-one system enables the city to eliminate pollutants from stormwater before it washes into the Pacific Ocean or San Francisco Bay.
Ex // Top Stories Feds launch heat forecast tool as San Francisco weather warms An interactive map from the federal government shows how vulnerable The City is to extreme heat But controlling costs and protecting ratepayers from dangerous floods are some of the reasons why the decision to close the Pierce Street outfall was the wrong one, according to current and former SFPUC and Public Works employees.
Abadie, considered by many of her SFPUC coworkers to be among the agency’s most knowledgeable engineers on outfalls, appeared disturbed in email conversations later that week about the data used to support an argument for closing the Pierce Street outfall.