U.S. Sens. Kamala D. Harris and Dianne Feinstein, D-Calif., introduced the St. Francis Dam Disaster National Memorial Act on Thursday. The legislation would establish a national memorial in San Francisquito Canyon to honor the lives of the 431 people who perished in 1928 when the dam collapsed and unleashed a devastating flood.

In terms of lives lost, it was California’s second-biggest tragedy and America’s worst civil-engineering failure of the 20th Century.

Already passed unanimously by the U.S. House of Representatives, the bill allows members of the Santa Clarita Valley Historical Society and others to raise private funds to erect and maintain a visitors center at the dam site, which is government land managed by the U.S. Forest Service. The Forest Service would continue to be responsible for the property.

“We should not forget the hundreds of lives lost during one of the worst tragedies in California’s history,” Harris said in a statement. “And while this monument will serve as a reminder of the consequences of a failure of infrastructure, it offers a lesson going forward.”

The failure of the dam led to heightened safety measures around the world, some of which are still used in dam construction today.

“It’s been almost 90 years since the catastrophic breach of St. Francis Dam, one of the most tragic events in California’s history,” said Feinstein. “The dam’s collapse had an impact on the entire nation, with news of the tragedy appearing in newspapers as far away as Maine. This monument will honor the more than 400 lives lost and serve as constant reminder of how critical investments in dam and infrastructure safety are to our communities. That message is just as true today as it was when this horrible event occurred.”

The bill would also establish a 440-acre national monument around the area that would be managed by the U.S. Forest Service, and it would authorize the U.S. Secretary of Agriculture to establish the memorial through the acceptance of donations. Backers intend to raise funds from the private sector to build and manage a visitors center.

The companion bill, H.R. 2156, by U.S. Reps. Steve Knight, R-Palmdale, and Julia Brownley, D-Westlake Village, cleared the House in July.

Dianne Erskine-Hellrigel, president of the Community Hiking Club, worked behind the scenes in crafting and promoting the legislation in Washington.

“I am thrilled that both Senators Feinstein and Harris have gotten behind this bipartisan legislation and have co-introduced it,” she said Thursday. “Now we can look forward to it passing in the Senate, and President Trump signing it into law. This will be a dream come true, not only for us, but for all the families of those who lost loved ones in the resulting flood.”

Donations for the memorial are already being collected by the St. Francis Dam Disaster Memorial Foundation. Checks should be made payable and sent to the SCV Historical Society, P.O. Box 221915, Newhall CA 91322, and should indicate “Dam Memorial” in the memo field. Contributions in any amount are appreciated.