As the first rain in 2018 swept into the Bay Area, the underpass at Oregon Expressway near Alma Street flooded once again, as it has numerous times over the years. Police shut down the busy roadway in both directions because of the water around 1 a.m. Tuesday.
The storm did not drop an especially significant amount of precipitation, but Ron Jackson, deputy director of Santa Clara County Roads and Airports, said pumps that usually take the water away stopped working that night. Technical engineers were still assessing the problem.
It isn't the first time the pumps have failed, despite some new equipment, and city of Palo Alto Public Works officials have discussed the issue with the county.
"The city has had several conversations with the county about improving the reliability of the pump station on Oregon. We do believe there is a reliability issue at this facility. We have communicated our concerns to the county," Jon Hospitalier, assistant director of public works, said.
Flooding in this location and the attendant road shutdown is likely to persist for a significant number of years. Limitations to the pump station and the inability to perform any significant upgrades will continue to impact flooding during the rainy season. To make any meaningful improvements would likely require a reconfiguration of the underpass, Jackson said. But those improvements are extremely costly and there aren't any plans in the works for a redesign, he added.
For the most part, the pumps function well, he said. They take treated groundwater pumped as part of hazardous materials contamination remediation from Hewlett-Packard and Varian sites in the Stanford Research Park and water from the city of Palo Alto and pump it into the stormwater system. But the combination of all of the water that normally flows through the system and additional rain runoff sometimes puts stress on the pumps, causing a breakdown. At times, the amount of water coming through the system is so significant that the county must funnel it into the sanitary sewer, he said.
"It's a very, very tricky location," he said.
"Two of the pumps were replaced in December 2012, he said, "but they are shoehorned in there. There is not much significant improvement we can do because of the physical constraints. We can only maintain what we have now," he said. "No matter what we do, things get in there," he said of debris and organic materials that can foul the pumps.
Jackson said he has not heard of any reconfiguration ideas and he does not know of any collaboration between the multiple agencies that would be involved in such an undertaking.
"It will be a big-money project to reconfigure a big area," he said, but added where to locate the pump operations, which could hopefully expand, would have to be a part of that redesign project.
City Public Works Director Mike Sartor said his department staff is aware the pump station isn't functioning as well as it can. The pump is undersized and doesn't have adequate capacity," he said.
Sartor said the city has had many discussions with the county about the issue. To some degree, each time it floods there are impacts on public works and police resources to make the area safe.
He didn't agree that the pump station is restrained by its size and location.
"There is always an engineering solution. From my perspective, it's not high on their (the county) priorities list," he said.