Warnings that flooding might not be contained if the predicted El Nino hits the Bay Area this winter, public officials said they are doing everything possible to reduce hazards to homes and residents if the notoriously volatile San Francisquito Creek surges out of its banks.
Standing on a dike where the creek jumped its banks and flooded an East Palo Alto neighborhood in December 2012, city and county officials discussed their efforts to reduce the hazards during a joint press conference on Wednesday, Oct. 14.
Those efforts include clearing the creek of debris and vegetation that impede downstream water flow to the San Francisco Bay, a new website that will give residents in flood-prone areas a two-hour flood warning, adding berms and retaining walls in troublesome areas, and coordinating disaster and emergency response.
Speakers at the media event included Len Materman, executive director of the San Francisquito Creek Joint Powers Authority (JPA); East Palo Alto Mayor Lisa Gauthier; Palo Alto Mayor Karen Holman; Gary Kremen, chair of the Santa Clara Valley Water District Board; Menlo Park City Manager Alex McIntyre and San Mateo County Supervisor Dave Pine.
The expected rainfall could equal or exceed that of 1998, where 70 homes in East Palo Alto and Palo Alto flooded, Holman said. About 200 people were evacuated, she said, and 1,500 properties were affected overall.
"While we can't control how much rain falls, we are committed to proactively doing everything possible to reduce the risks of flooding, supporting our communities and working with our neighborhoods to be prepared," Holman said. "Our first priority remains the safety of our communities and the protection of homes and that is where we have been and will continue to focus our efforts."
The broad collaboration is thought to be the first of its kind for reducing flood risks, Pine said.
"Hopefully, these efforts will make us all better off and protect our residents," said Gauthier, whose home is in the Gardens neighborhood that flooded in 2012. Although her home was not affected, those of her neighbors two blocks away were, she said.
Since, a 1 1/2-foot-tall berm made of concrete and sandbags has been added to 400 feet along the creek bank where water surged out of, and another 600 feet of berm closer to the bay will be completed by Nov. 1, City Engineer Kamal Fallaha said.
Another 2-foot-tall retaining wall will be constructed in the coming weeks along a section of creek on Woodland Avenue near University Avenue in East Palo Alto that will match the height of an existing wall on the Palo Alto side to keep rising water contained, Fallaha said.
Palo Alto and Menlo Park officials have also shored up the area near the Pope-Chaucer Bridge with berms. The bridge is a bottleneck for debris that causes flooding, and it will later be modified and widened through a broader flood-control project through the JPA.
Caltrans has been working this summer on a new, wider bridge at San Francisquito Creek that goes under U.S. Highway 101 to improve creek flow in that area. That work won't be completed by this winter, but a retaining wall that currently keeps water from entering the work site will be removed this month so that it won't affect downstream water flow during the rainy season, officials said.
Joe Teresi, Palo Alto senior engineer, said a pump station was not in place during the 1998 flood that affected Palo Alto. Built in 2004, it is designed to move water faster away from Palo Alto. But that could mean more water for East Palo Alto, so the pumps would be turned off when the water reaches a critical level, he said.
Crews walked the creek in August to identify potential blockage areas and have since removed vegetation and debris that would impede water flow downstream.
"Our city crews removed 2,700 pounds of trash and 750 pound of recyclables from Menlo Park's 1.3 miles of creek," McIntyre said.
Additional sandbag locations are also being set up, and water district officials are looking at funding crews to help seniors and other residents with filling and delivering sandbags to their homes, Kremen said.
East Palo Alto will host a sandbag-filling event on Oct. 24 at the Tara Road municipal yard from 9 a.m. to noon. The city has 133 volunteer emergency workers at the ready and has conducted drills to aid residents should flooding occur and in the event of evacuations, Gauthier said.
The JPA also debuted a new website at sfcjpa.org/floodwarning, which displays a color-coded map showing the likelihood of flooding at key points along the creek and in specific neighborhoods.
"The site provides a two-hour warning where we can now anticipate points where the creek levels will over-top. The site also makes rain and creek-flow data during major storms both useful and user friendly," Materman said.