When the storms keep coming, when the land below your feet erodes and the industry that has sustained you starts to disappear, how do you stay in the place you call home? How do you leave—where do you even go?

Since Hurricane Katrina battered Louisiana in 2005, followed by a series of disasters linked to climate change and the Deepwater Horizon oil spill, these questions have plagued coastal parts of the state. In a sweeping plan released Wednesday, the state issued a blueprint for coping with the impacts of a warming planet, including a human migration that has already begun.

"Louisiana is in the midst of an existential crisis," the report says. "Its response to this crisis can either lead to a prosperous renaissance or to a continued and sustained cycle of disaster and recovery."

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The plan, Louisiana's Strategic Adaptations for Future Environments (LA SAFE), looks at future flood risks in six coastal parishes and recommends a series of policy changes that could help mitigate those risks—from enhanced transportation routes to elevated houses and new urban centers.

Climate change will only exacerbate the flood risks across the state, the report says. Louisiana's ability to adapt will dictate just how coastal communities are able to survive.

"There are ways for us to make coastal communities more livable, resilient and viable post-disaster, just by making the whole community more resilient ... so that businesses and government services can all get back to work more quickly after a disaster," said Pat Forbes, executive director of Louisiana's Office of Community Development, which produced the report along with the Foundation for Louisiana.

In other areas, people will have little choice but to leave as the water rises. The plan, in a departure from many adaptation reports, also focuses on how inland areas can prepare for an influx of new residents from the coasts.

"There's a sort of self-displacement that's occurring over the past 15 years or so," Forbes said. As large numbers of people move out of coastal communities, the shift is likely a sign that they are sick of flooding, worried about inability to get to schools or jobs or unable to pay rising flood insurance rates. "I'm sure it's a combination of all those things and more," he said.

After Hurricane Katrina, Alan Sessum rebuilt his home on a bayou near Venice, Louisiana. The hurricane had left nothing of his previous home, built on land accessible only by boat. Credit: Mario Tama/Getty

Those who are unable to leave, or choose not to, can find themselves faced with a host of new problems.

"Poverty rates increase, you've got lower capacity to fund risk reduction and mitigation activities, and a decline in social services," said Liz Williams Russell, the coastal and climate program director of the Foundation for Louisiana, a social justice organization that makes sure communities of color have a voice in disaster response and planning.

One of the parishes, for instance, has seen three schools shut down in the past 15 years. In another parish, residents have to drive an hour and a half to buy groceries.

Strategies for Climate Resilience — and Retreat

Louisiana is among the most flood-prone states in the nation. It has lost nearly 2,000 square miles of land since the 1930s, and could lose 4,000 square miles more over the next 50 years, according to the report. It's not just along the coast, either—every one of the 64 parishes in the state has flooded in the past five years.

With global warming fueling sea level rise, and land in the delta subsiding, local leaders need to be prepared to support "planned retreats from areas that are becoming unsustainable," the state plan says.

That means being prepared to offer safe, affordable housing, job training and other economic opportunities, as well as basic services. The plan also stresses the importance of addressing the "complex social and culture needs" of coastal communities and residents who are forced from their homes by rising water, and developing "a sense of place that helps build community."

The plan includes strategies for six at-risk parishes and $47 million to launch projects in each location.

In Plaquemines Parish, those plans include building a safe-harbor for the fishing vessels that are central to the local economy, and constructing a wetland park to help mitigate flood risk through better stormwater management.

In St. John the Baptist Parish, the plans include mixed-use housing developments to respond to residents' concerns about housing stock declines in quantity and quality as the population has moved away.

Shrimpers Watch Their Communities Disappear

Acy Cooper, Jr., a 58-year-old shrimper in Venice, Louisiana, has seen the changes described in LA SAFE first hand. Cooper comes from a family of shrimpers—his 83-year-old father is still at it, as are all three of Cooper's kids.

"We were all hopeless after Katrina—we lost everything," Cooper said. "We went back and rebuilt, but we have to prepare ourselves for the next time. There's gonna be a next time."

From 2000 to 2010, Venice lost half its population, according to the U.S. Census. Cooper has seen friends and family leave, and he bought a house further inland, too. But he plans to stay in Venice as long as he can.

The LA SAFE plan looked at the shrimping industry and found three options for shrimpers: sell their catch for more money, catch more shrimp, or find a new line of work.

Cooper, who is the president of the state's shrimp association, says the first two options are unlikely.

Over the past three decades, Cooper said, he's seen big changes to the industry, mostly due to competition from foreign-sourced shrimp. He expects more changes coming from climate change.

Coastal erosion in Louisiana has been causing the state to lose about a football field of land every hour and a half, on average. "We know that erosion will wind up taking a lot of the estuaries in the long term—we're starting to see it now," Cooper said. "Long-term, it'll eat up the marshlands and then there's nowhere for the shrimp to grow and breed."