FORT LAUDERDALE, Fla.—Along the canals that slice through downtown Fort Lauderdale, dozens of freshly razed lots sit ready for construction, many nestled next to historic riverfront mansions and yachts bobbing dockside. Cranes and half-built high-rises tower overhead. Everywhere, there are signs that this mid-size city of 170,000 is thinking big.

Mayor Jack Seiler says the goal is to turn Fort Lauderdale into "the city you never want to leave." The population is expected to grow by a third, more than 50,000 people, in the next 15 years. Nearly 5,500 apartments and condos are, or will soon be, under construction and developers are seeking to build another 2,400 units in the next few years. The city processed 26,000 building permits with a construction value of $1.8 billion last year alone.

But as the coastal city's skyline climbs upward, Fort Lauderdale—nicknamed the Venice of America for its 165 miles of canals—is slowly becoming an edifice of risk as climate change lays siege to its shores.

Already, water regularly creeps over sea walls, lapping against foundations every few weeks. When the earth, moon and sun align to drive waters as much as 18 inches above normal, the resulting King Tides inundate whole streets and neighborhoods. The city is racing to put climate resiliency measures in place, but they face a nearly impossible foe.

Mayor Seiler and his city typify the imminent risks much of South Florida faces from global warming.

"We are already experiencing the effects of a changing climate," a coalition of 15 South Florida municipal leaders wrote to Sen. Marco Rubio and former Gov. Jeb Bush last month, urging the state's two then-Republican presidential candidates to pledge firm steps against global warming.

"Sea levels off the coast of South Florida rose about eight inches in the twentieth century. As a result, we have seen more tidal flooding, more severe storm surges, and more saltwater intrusion into aquifers," they wrote. "By 2050, mean sea level around Florida is expected to rise about a foot, a shift which could wipe out as much as $4 billion in taxable real estate in the four-county region of Southeast Florida. At three feet of sea level rise, the loss could total $31 billion, with large sections of the Everglades, the Florida Keys and the Miami metropolitan region under water."

Scientists, city officials, planners and policymakers say that in the coming decades, climate change will impact nearly every aspect of life in Fort Lauderdale and the rest of South Florida, from the price of flood insurance to home values, drinking water supplies, infrastructure, the economy and health.

"There are winners and losers," said Keren Bolter, a climate scientist who grew up here and studies sea level rise. "But in a few decades, most waterfront properties in Fort Lauderdale will flood for days, weeks at a time."

Yet construction continues unabated, often without any thought of long-term climate impacts. The risks will be borne not only by developers splurging on the region's extraordinary building boom, but by millionaires already ensconced on prime lots lapped by high tides and on the working poor who inhabit the soggy areas along verdant inland canals.

"See that house right there—the white ranch-style one?" Bolter said one day in late November, during a balmy, sundrenched ride on a yellow water taxi through Fort Lauderdale's waterways. She glanced at her smartphone to consult a database compiled by her company, Coastal Risk Consulting. "That property flooded 11 days last year. By the late 2030s it could have water on its property 267 days per year."

OMINOUS TRENDS

Federal researchers estimate that sea levels in South Florida could rise another 2 feet by 2060 and nearly 6 or 7 feet by 2100. Heavy rainfalls could become more frequent and intense. The most intense hurricanes could form more frequently as well.

This all has dire implications for Fort Lauderdale. The 165 miles of waterways that give the city its charm now threaten its viability. These canals once functioned as the city's gravity-based drainage system. But rising seas and heavier deluges are rendering it useless—not just overtopping the defenses and eroding roads, bridges and seawalls, but undermining the city's defenses from below.

Nancy Gassman, assistant director of public works, and her colleague Marie Pierce, who manages the city's stormwater operations, described the problem during a recent tour of the town. A post-Thanksgiving storm had just dumped nearly 3 inches of rain, and the tide was running high. A woman sloshed by in knee-high rubber boots, walking her dog. Like buoys in pools of water, signs poked up from flooded roads advertising waterfront properties for sale and declaring that tax dollars were at work nearby on flood mitigation projects.

"This isn't even King Tide flooding," said Pierce.

The Public Works Department has installed 59 one-way valves, at a cost of up to $25,000 each, on drainage pipes across the city to keep high tides from backflooding into streets. The city has plans to install another 110 valves in the next year.

But the problem, Pierce and Gassman explained, is that if rain floods the street or if canal levels top seawalls during high tide, the valves won't open and the water would sit temporarily in roads and lawns, even spilling into homes. Street signs warn drivers to slow down lest they push waves through cracks under front doors: "No Wake."

Fort Lauderdale has considered installing pump systems to carry floodwater out to sea, but that is expensive, requires a lot of maintenance and generates greenhouse gas emissions, said Gassman. "We're going to use passive systems as much as we can," she said.

Fort Lauderdale can't take the simpler approach of cities like New Orleans or Amsterdam of keeping floods at bay with levees and seawalls. Like most of South Florida, its porous limestone bedrock lets water creep under and through the foundations of any defense, said Hal Wanless, a climate scientist at the University of Miami.

"As someone else once said, we're basically doing a lot of rearranging of deck chairs on the Titanic. As people look at how high they will have to go, and how much it will cost, it becomes clear that at a certain point some parts of these communities will no longer be able to maintain the infrastructure," he said. "There's no running from the fact that this is becoming an increasingly challenging place to live."

Ahead of last fall's record-breaking King Tides, city employees spent days deploying tiger dams (plastic tubes filled with water), building sandbag walls and manually plugging dozens of individual storm drains to keep the water back. Workers also put out "No Wake" signs. Vacuum trucks sucked up water from roads. These efforts kept some sections of the city dry, but hundreds of homes and streets still flooded.

UNEVEN IMPACTS

None of that work—at least not yet—has been done in the inland, lower-income communities. Gassman explained the city is prioritizing its work based on who is immediately at risk, not by income level. Wealthy neighborhoods closest to the ocean have the worst flooding right now, she said.

Environmental justice activist Audrey Peterman stands next to her boat in Fort Lauderdale.

But as the city's canals wind inland along the edges of minority and low-income neighborhoods, the seawalls disappear. Only a thin line of vegetation protects homes as river levels rise and water bubbles up through the bedrock. It won't take much sea level rise to put these communities at risk. Black and Hispanics make up nearly 45 percent of Fort Lauderdale's population.

"Doesn't it feel just like the Everglades?" said Audrey Peterman, an environmental justice activist, as she stood on the edge of a small wooden pier in Fort Lauderdale's New River. It is early December. Dense stands of mangroves and pond apple trees lined the riverbanks while murky brackish water meandered downstream.

"It is hard to remember we are in the middle of Fort Lauderdale," she said. "That those plants are all that stand between the water and the city's historically black neighborhood."

The good news is that much of Fort Lauderdale's historically black neighborhood, known as Sistrunk, sits on a small hill a few feet higher in elevation than the wealthy oceanfront areas, said Peterman. But environmental justice advocates worry that even if these communities are spared the worst of sea level rise, they could still lose their homes as wealthier families look to relocate to higher ground.

"It is climate gentrification," said Nicole Hernandez Hammer, an expert for the Union of Concerned Scientists on how climate change impacts Latinos in Southeastern states. But in South Florida, with the ocean to east, the Everglades to the west, and sea level rise bubbling up through the bedrock, there will be nowhere else for these communities to go.

"These are the people who have the hardest time rebounding from disaster, and they are getting the least protection," said Hernandez Hammer.

RESILIENCY AND RISK

Despite Florida being one of the most at-risk states, its politicians have made climate change a taboo topic. Its governor, Rick Scott, has eliminated nearly all of the state's climate programs and banned government employees from using climate-related terms in official business. Bush, who dropped out of the presidential race last month, and Rubio, who remains one of the Republican Party's White House contenders, deny the climate is changing because of human activity. Their rejection of the science is particularly pertinent considering Florida's prominent role in American politics. With 19.8 million people and 29 electoral votes, it is a crucial swing state that has successfully predicted the presidential election outcome nine out of the last 10 cycles, dating back to 1976.

With almost no leadership coming from the capitol, Florida communities concerned about global warming have largely had to fend for themselves. In 2009, the four southernmost counties in the state—Broward (which includes Fort Lauderdale), Miami-Dade, Monroe and Palm Beach—created the Southeast Florida Climate Compact to coordinate global warming mitigation and resiliency work on a regional scale.

Fort Lauderdale adopted a climate resiliency strategy in 2013 as part of the city's 30-year development plan. The ultimate aim is to make the city "the most resilient community in the United States" to the impacts of climate change, according to the plan, known as Fast Forward Fort Lauderdale.

It launched the nation's first mandatory climate training program for all city employees, educating everyone from firefighters to administrative assistants on climate science and how global warming will impact Fort Lauderdale. More than 1,700 workers have gone through the program so far.

High water in Fort Lauderdale

It has also designated 16 neighborhoods as Adaptation Action Areas in a pilot program to test climate resiliency measures. Projects are set for low- and high-income neighborhoods, and include updating stormwater management systems, fixing sea walls, replenishing beaches and converting stretches of concrete into rain gardens that funnel floodwater underground.

Fort Lauderdale officials have been vocal about the enormity of these challenges. The city plays a lead role in the Southeast Florida Climate Compact. It is considered by many to be the leader in climate change work in the state, even more so than higher-profiled Miami to the south.

Until some of its largest projects are finished, however, Fort Lauderdale's public works' staff will continue its Herculean task of fighting flooding street by street, storm by storm and high tide by high tide.

All this is complicated by Fort Lauderdale, like most U.S. cities, being a puzzle of private, local, county and state-run roads.

"We can fix a bunch of storm drains, but to protect the neighborhood you might have to get the state and county to fix their infrastructure, too," said Gassman, the public works official. "It often falls on the local jurisdiction to get them to do that."

Despite the city's many aggressive resiliency efforts, it has been reluctant to take steps that might imperil its real estate growth, which added more than $329 million in taxes in 2015.

Florida building code requires new construction, except one- and two-family dwellings, be elevated one foot above the current floodplain. Fort Lauderdale follows that code, and hasn't required anything stricter except to include single family and duplex homes. Most of Florida's strictest building codes are designed to prevent hurricane wind damage, not flood damage.

The city also caps seawalls at 6 feet for aesthetic reasons, which prevents homeowners or developers from building in higher defenses even if they wanted to.

Some developers are starting to think about climate risks, but most aren't, said Peter Zalewski, a real estate expert who closely tracks South Florida's building boom. Preventative measures are expensive and buyers aren't demanding them, so developers don't consider the extra cost worth it.

Construction cranes loom high over Fort Lauderdale.

Jenni Morejon, the director of Fort Lauderdale's department of sustainable development, said the city couldn't make huge changes to its building code without "direct and dramatic economic impact... It wouldn't be palatable to developers." Instead, the plan is to introduce stricter building standards gradually over the next half-century as climate projections, technology and construction methods improve, she said.

"But yes, that means you'll have some buildings built in the last five years that likely won't make it in next 30 to 40 years," said Morejon.

Realtors aren't disclosing those risks when selling properties, Zalewski and other experts said. Bolter said her company, Coastal Risk Consulting, contacted the online real estate company Zillow about including their property-level flood risk projections into their website, but Zillow declined. This is despite the fact that its site shows data for things like projected home value and mortgage payments.

"All of South Florida is building like crazy, like there is no tomorrow, which is true, unfortunately," said Wanless, the University of Miami scientist. "The plan is to build these homes and sell them to the Iowa pig farmer who has worked all his life to retire here, or get a nice investment for his grandchildren. They are being hoodwinked."

This leaves homeowners and banks on the hook for countless dollars in lost property values.

"If we follow the federal government's estimates, we could be at 6.6 feet by the end of the century," Wanless continued. "That curve puts us at 2 feet by 2048. That's barely a mortgage cycle away."

Photos by Katherine Bagley