More than 20 years after a massive storm swelled the San Francisquito Creek until it rose higher than the Pope-Chaucer Bridge, sending water onto nearby streets and into homes, two plans aimed at keeping the creek within its banks are finally emerging.

The San Francisquito Creek Joint Powers Authority, the regional agency that recently completed an equally ambitious flood-control project in the downstream area of the creek, has just released a draft environmental-impact report (DEIR) for improving flood control in the upstream area near the Pope-Chaucer Bridge, which connects Palo Alto and Menlo Park.

At the same time, Palo Alto is moving ahead with its own plan to replace the Newell Road Bridge, a narrow structure downstream from the Pope-Chaucer that has been designated as "obsolete" by Caltrans and that the city has been looking at replacing for more than five years. The environmental analysis for the Newell bridge plan will be released by the city in the coming months, after which the project would be vetted by the Planning and Transportation Commission and ultimately the City Council.

While the projects both seek to address the need to improve flood control around the volatile creek, the two have evoked very different reactions from the public: A proposal to replace the Newell Road structure with a larger span has been subject to intense criticism from some nearby residents, but the creek authority's proposal to build a new Pope-Chaucer Bridge is winning support from neighbors.

Norm Beamer, president of Palo Alto's Crescent Park Neighborhood Association, said he and his neighbors support the reconstruction of the Pope-Chaucer Bridge, which would be undertaken in conjunction with the widening of the channel at five locations. Concrete structures along the creek would give way to natural habitats, increasing the flow capacity of the creek. This "preferred alternative" presented in the impact report represents "the most bang for the buck," Beamer said.

"It's the least disruptive and it will solve the flooding problem," Beamer said. "Maybe not the 100-year-flood (which has a 1 percent chance of happening in any given year) but the 1998-level flood, which is the largest we've ever had."

For some residents, who still remember the massive damage caused by the February 1998 flood, the preferred alternative is particularly significant for what it does not include: namely, floodwalls. The DEIR does consider an alternative that combines the replacement of the Pope-Chaucer Bridge with the construction of floodwalls at the top of the creek's banks. The preferred alternative, however, eschews floodwalls in favor of widening the creek channel.

An unpopular option, floodwalls "would be very disruptive to property owners," Beamer said.

"I think a lot of people would rise up and be very opposed to it," Beamer said. "That would either delay or completely scotch the whole effort."

Trish Mulvey, a resident of Palo Alto's Duveneck/St. Francis neighborhood who has been following the creek authority's flood-control projects since the agency's inception (she was part of a citizens group that successfully lobbied for the creation of the JPA), also lauded the agency for choosing channel widening over floodwalls, which would have a greater environmental impact. The new environmental analysis notes that the floodwall alternative may have "substantial impacts on aesthetics and trees on top of bank."

In addition to the two alternatives in the new report that call for replacement of the Pope-Chaucer Bridge, the document also makes a case for a third alternative: building detention basins in the upstream area, on land owned by Stanford University. The university is already looking at modifying Searsville Dam by creating an opening at the base of the dam, excavating sediment in the reservoir behind the dam and creating a channel to upstream areas.

"Very high flows that exceed the capacity of the new opening would back up behind the dam, thereby providing temporary floodwater detention," the DEIR states.

According to the document, Stanford's proposed project, when combined with the reconstruction of Pope-Chaucer Bridge, would accommodate a 100-year flood. In short, it would give residents of Crescent Park, Duveneck/St. Francis and the Willows in Menlo Park the flood protection they've long awaited. If Stanford does not move ahead with the Searsville project, the DEIR proposes creation of two detention basins along the creek, between the dam and Interstate Highway 280.

Mulvey, who served on a community-stakeholder group that Stanford had put together to provide comments on Searsville Dam alternatives, said she believes the upstream detention basins should be pursued in conjunction with the replacement of the Pope-Chaucer Bridge, rather than as an alternative that could replace the bridge project. And while the decision ultimately rests with Stanford, Mulvey said she is optimistic that the project will move ahead.

There is, however, one potential obstacle standing in its way: Palo Alto's plan for the Newell Road Bridge, which has been moving through various phases of analysis for more than six years. Mulvey said it will be critical that the Newell Road Bridge be replaced before work on Pope-Chaucer moves ahead. Allowing more water to pass through Pope-Chaucer would cause substantially more flooding at Newell if that bridge isn't fixed by then, she said.

"The projects have to be sequenced so they can work together smoothly," Mulvey said.

To date, the city's path to replace the Newell Road Bridge has been anything but smooth. During public hearings in 2013 and 2014, residents criticized the plan and expressed concerns that a larger bridge, coupled with a proposed bridge realignment, would bring more traffic into their neighborhoods. Some argued that the city should remove the bridge altogether or create a smaller span only for bicyclists and pedestrians.

A new report from the city's Public Works Department suggests that staff is backing away from some of its most ambitious proposals for the Newell Road Bridge, which was constructed in 1911. Its environmental analysis is considering five alternatives: a one-lane bridge with two-way traffic controlled by a signal; three options for a two-lane bridge (with different plans for realigning Newell Road); and the "no build" alternative. The preferred alternative, according to staff, calls for a two-lane bridge on the existing alignment of Newell Road. As such, it obviates the need to raise the roadway.

Both bridge projects still have to overcome numerous hurdles, including getting the needed funding. The creek authority is banking on various grants to implement its preferred alternative for the Pope-Chaucer Bridge, which creek authority Executive Director Len Materman said is expected to cost about $35 million. This includes $8 million from the Federal Emergency and Management Agency. The city, for its part, plans to seek a Caltrans Highway Bridge Program grant to cover the construction costs for the Newell Road Bridge once its environmental analysis is completed.

The release of the JPA report, which paves the way for the bridge reconstruction, is a significant milestone in the creek authority's long journey toward improving flood protection in the upstream area. The agency hopes to launch construction in 2020, though Materman acknowledged in his executive report that "because of the complexity of this project, beginning construction in 2021 may be more realistic."

Related content:

• Crescent Park neighborhood resident Rom Rindfleisch discusses the efforts to prevent San Francisquito Creek from flooding on an episode of "Behind the Headlines," now available on YouTube.com/paweekly/videos, or our podcast page at PaloAltoOnline.com/podcasts.

• Officials unveil first phase of San Francisquito Creek flood protection

• Stanford removes dam, giving endangered fish room to roam