SAN FRANCISCO - Sea levels in California are projected to rise up to 55 inches by the end of the century, so climate advocates are calling on Congress to fund coastal restoration projects to mitigate potential flooding.

More than 100 groups signed a letter calling on lawmakers to include $10 billion for such projects nationwide in the proposed infrastructure bill.

Seventeen-year-old Amelia Fortgang, chair of the Bay Area Youth Climate Summit and youth leadership council member at Earth Echo, said the time for action is now.

"At the same time that the skies turn orange from wildfires, our coasts are moving inward," said Fortgang. "And this is a major issue because in California 85% of our residents live and work in coastal counties."

Reports done for the Governor's Climate Adaptation strategy predict that if nothing is done, coastal flooding could threaten $100 billion in property and infrastructure.

The state already has a list of shovel-ready projects including restoration of wetlands from San Diego to Santa Barbara and construction of a living shoreline around San Francisco Bay.

Jean Flemma, director of the Ocean Defense Initiative and co-founder of the Urban Ocean Lab, said natural projects have proved more effective at protecting the shore than hard infrastructure such as sea walls.

"Rebuild a wetland, or restore a marsh or sea-grass beds," said Flemma, "so that you are creating a natural buffer between the coast and the communities, and the rising seas and more intense storms that are happening now as a result of of climate change."

Advocates estimate that coastal resilience projects would create tens of thousands of jobs for engineers, biologists and cleanup and construction crews.

A 2017 analysis from the National Oceanic and Atmospheric Administration found that coastal-restoration projects funded with stimulus dollars created around 15 jobs per million dollars of investment.

Small sections of the kelp forests off the Mendocino coast are starting to recover with improved environmental conditions, thanks to a conservation program which sent divers to remove 45,000 pounds of purple sea urchins.

The urchins have devastated the once massive bull kelp forests, leaving a lifeless barren behind.

Dan Abbott, kelp forest program director for the Reef Check Foundation, said it is the first large-scale kelp-restoration project of its kind in northern California.

"It's not back to where it was, say pre-2015," Abbott acknowledged. "It's still only about 20% of the historical average. But again, it's only like a year and a half in. And it's a very encouraging result."

The purple sea-urchin population has exploded in the last eight years or so, partially because a wasting disease has decimated their chief predator, the sea star. In addition, the area has no sea otters to keep the urchins in check, because the otters were hunted to extinction in the early 1900s.

Sheila Semans, director of the Noyo Center for Marine Science in Fort Bragg, said the kelp forests there have recovered 5 to 10 percent - and serve as crucial habitat for hundreds of species.

"The sea lions hunt in it, the abalone eat it, the rockfish hide in it," Semans outlined. "There's just so many ecosystem services that it provides. On top of that, it sequesters carbon, and it buffers wave action along the coast."

The Noyo Center also is working to create a new fishery for purple urchins, which can be fattened up in an aquaculture facility and sold. The California Department of Fish and Wildlife said it plans to develop a comprehensive statewide Kelp Recovery and Management Plan over the next five to 10 years.

Support for this reporting was provided by The Pew Charitable Trusts.

Marine-conservation groups are celebrating after the U.S. House passed the America COMPETES Act on Friday.

The bill primarily boosts semiconductor production in the U.S. but a lesser-known provision would phase out an older type of fishing gear called drift gill nets in federal waters, something environmental groups have sought for decades.

Ben Enticknap is Pacific campaign manager and senior scientist at the nonprofit Oceana. He said the mile-long, nearly invisible gill nets are incredibly dangerous for marine life.

"They are set at night in the epicenter of ocean wildlife off the coast of southern California to catch swordfish," said Enticknap. "But they also catch whales, dolphins, sea turtles, sharks and many, many other animals."

The state of California already is phasing out its state drift gillnet permit program, which offers fishing crews cash to turn in their nets and permits, and helps them buy a new, safer type of gear called deep-set buoy gear.

All but four fishing boat captains in Southern California have begun the transition - and those four will have to follow if the bill becomes law.

Opponents of the bill, referring primarily to its provisions on manufacturing, say it is not tough enough on China.

Enticknap noted that it also would ban the sale of shark fins in the United States.

"We've already prohibited shark fins in California and Oregon and Washington," said Enticknap. "And this kind of takes that same approach that's already been passed by a number of states and makes it national."

A version of the COMPETES Act already has passed the U.S. Senate. Now the two have to be reconciled and passed again in both chambers before the final version can go to President Joe Biden's desk.

SAN DIEGUITO LAGOO, Calif. - Coastal protection groups are pressing California to prioritize so-called "blue carbon" ecosystems in the fight against climate change.

Dozens of groups have sent a letter to the head of the California Natural Resources Agency - asking for action to protect existing wetlands and near-shore areas, and restore those that have been degraded.

Gilly Lyons, an officer with the Conserving Marine Life in the United States program of The Pew Charitable Trusts, is among those who signed the letter.

"The request from the signers is to protect biodiversity, to store and sequester carbon, and to mitigate the effects of climate change that we're already living with," said Lyons, "things like ocean acidification, storm surges, coastal flooding, etc."

The letter comes during the public comment period for a draft of the CNRA's new "Natural and Working Lands Climate Smart Strategy," to be finalized early next year.

Last year, Gov. Gavin Newsom issued an executive order requiring state agencies to act to accelerate the natural removal of carbon and build climate resilience, especially in lower-income communities.

Angela Kemsley is conservation and communication manager at the group WILDCOAST, which is currently restoring two lagoons in San Diego County. She said natural features like eelgrass beds are important tools in climate mitigation.

"They're actually much more efficient at storing this carbon than land-based plants," said Kemsley. "And so, they're able to take a bunch of carbon out of the atmosphere, store it in the soil - and that helps to fight climate change."

According to the U.S. Fish and Wildlife Service, 90% of California's historic wetlands have been drained for agriculture and development over the past century.