Grappling with intense bursts of rainfall in recent years, water officials are making headway on a series of construction projects meant to reduce flooding throughout San Francisco.
But residents of two historically flooded neighborhoods in Mission Terrace and the Mission District may be disappointed to learn that the San Francisco Public Utilities Commission is still years away from relieving their water-related woes.
While under negotiation, Caltrans does not want to move forward with one project meant to drain the cul-de-sac at the end of Cayuga Avenue that’s known to flood during storms, according to SFPUC Project Manager Stefani Harrison.
Water officials are also still deciding whether to spend upwards of $150 million to reduce “prolific” flooding during storms that mostly affects just four blocks near 17th and Folsom streets, Harrison said.
“It’s such a challenging thing to fix,” Harrison said in an interview Monday. “We’re talking about this sunken area that … no matter what we do, even if we can move water away faster, this is always the place where water will go.”
The news comes after an especially wet winter in San Francisco.
The City experienced flooding twice during the first three months of this year alone and has continued to have an unusually high amount of torrential downpours in recent years, according to Harrison.
The flooding is the result of too much pressure on underground pipes. It typically lasts between just 15 to 20 minutes but is known to wreak havoc on basements in neighborhoods at the bottoms of hills.
“For the people it impacts, it’s very disruptive,” Harrison said. “To somebody’s home, it’s invasive, it’s just an ugly thing that happens.”
The SFPUC plans to reduce flooding on Cayuga Avenue through a $12 million project that calls for digging out an area beneath Interstate 280 that causes water — and whatever else is on the street — to pool in the cul-de-sac.
During heavy rains, the water would instead flow onto Caltrans property. The SFPUC plans to build a wall to prevent water from running onto the freeway, as well as to support the freeway after removing land beneath it.
But Caltrans has concerns about changing the support structure of the freeway, according to Harrison.
“They’ve known about this situation for more than 50 years,” said Cayuga Avenue resident Blane Bachelor. “It’s so troubling to me that not just Caltrans but city leadership has done zero to fix this. It’s just more excuses and more reasons not to do it.”
A Caltrans spokesperson did not respond to a request for comment, but Harrison said the agency had concerns about changing the structural area beneath the freeway.
Bachelor said the last time Cayuga Avenue flooded was early morning Jan. 20.
“This is a biohazardous situation that affects our health, our welfare and our wellbeing,” Bachelor said. “It is just reprehensible.”
The project is still under negotiation and water officials hope to have it completed by 2019.
As for the area near 17th and Folsom streets, water officials decided to build infrastructure to move rainwater to Mission Creek after reviewing dozens of options, according to Harrison.
However, the SFPUC still has to decide whether to increase the size of the underground pipes — which would require digging up about 1.5 miles of streets — or tunneling from the area of 17th and Mission streets to the creek.
Both options are estimated to cost between $150 million and $200 million and would not be completed until 2024.
Meanwhile, the agency is hoping to complete two projects in the near future and has funding for a third.
The SFPUC is scheduled to break ground on a project that will reduce flooding near Foerster Street and Mangels Avenue in Sunnyside this spring or summer, and finish a project on Urbano Drive in Ingleside by fall.
The agency also has found $23 million in funding for changes to the area near Wawona Street in West Portal by 2020.
Additionally, the SFPUC has rolled out a series of non-infrastructure remedies like flood barriers, and is even considering buying out property in The City to avoid expensive construction projects like the one at 17th and Folsom streets.
“We’re asking the question about whether it’s feasible,” said SFPUC spokesperson Charles Sheehan. “It’s an idea that we’re exploring.”