"This isn't something that's coming," she later told a group of bay shore residents and officials. "It's here. We just happen to live in a place that will affect us sooner."
Wren lives on tiny Money Island - more a peninsula of bayfront land with about 40 small homes and trailers in Cumberland County.
Just visible across the grassy marsh is Gandys Beach with 80 homes. Farther south, Fortescue with 250 homes. All three are steadily disappearing.
On the Atlantic coast, beach replenishment masks the effects of sea-level rise. But along the low-lying bay shore, veined with creeks, the problems are striking.
With each nor'easter, more of the beachfronts erode. More of the streets and driveways flood. Septic systems, inundated with salt water, are failing.
"We're seeing beyond the normal damage," said Steve Eisenhauer, a regional director with the Natural Lands Trust, which has a 7,000-acre preserve in the area. "We see the problems getting worse."
In the last century, sea level in the bay has risen a foot, gauges show, partly because the warming ocean is expanding and polar ice is melting. Also, New Jersey is sinking.
All the while, humans have been pumping more and more greenhouse gases into the atmosphere. The planet's average temperature has increased.
"All those links are very strong," said Pennsylvania State University's Raymond Najjar Jr., an expert on climate change in Mid-Atlantic estuaries.
"The reason the sea is rising as fast as it is in the Delaware Bay is human-induced climate change," he said, echoing many experts.
Sea level is rising faster now than in the early 20th century, and scientists expect it to rise even faster in the future.
The three towns' beachfronts and marshes have always been nibbled away by ship wakes, storms, and more typical erosion - but sea-level rise, combined with more frequent and intense storms, makes them all worse.
Can these three communities, all within Downe Township, adapt to climate change?
Or is there a point beyond which no amount of money can stop the sea? Should everyone relocate?
It's been done. After a $1.8 million seawall in nearby Sea Breeze failed a year after being built, the state bought out the 23 remaining households three years ago for $3.3 million. Tiny Thompson's Beach and Moore's Beach are gone, too.
These are special places, where people look out their windows and see eagles soaring. The bay turns red at sunset. Salt marshes thick with aquatic life stretch for miles.
With marinas in Fortescue and Money Island, they are among the last places in South Jersey where people can access Delaware Bay - vital for generating support to preserve the rich habitat.
But, like Wren, residents sometimes see white caps in their driveways.
Downe officials have come up with a $50 million plan to not only shore up the shore, but also add amenities across the township to draw tourists who could revive the economy.
The plan, which would cost the equivalent of $31,500 per resident, calls for bulkheads and truckloads of sand, restrooms, picnic benches, nature-viewing areas, and a township visitor center.
Officials identified nearly 30 "potential" funders - from agencies to nonprofits. But many feel the project is a long shot.
Meanwhile, bumper stickers are plastered on homes: "No retreat. Save the Bayshore communities."
"I refuse to give up one house, one lot, one piece of land," said Robert Campbell, Downe's mayor. "These towns are 200 years old . . . It's a special place. We've got to preserve it."
Their survival is also fiscally crucial; they represent half of Downe's tax base.
He and others blame flooding not on sea-level rise but on the decline of dikes once used for salt hay farming; (Scientists say the dikes blocked the tides from naturally bolstering mashes with sediment.)
Campbell also blames the state for being too tough in issuing permits for bulkheads and jetties.
After Hurricane Irene struck in 2011, the town put up temporary bulkheads. The state issued violation notices.
Now, those structures need restoration, too.
'We can survive'
Before modern travel made all the Atlantic beaches so easily accessible, Delaware Bay was the shore that many Philadelphians went to.
In the late 1800s, Fortescue was the Cape May of the bay shore, with hotels and a boardwalk.
"We are so rich in our history," said Dennis Cook of Money Island, who specified in his will that his ashes be thrown off his pier. "We can survive."
Or at least they feel compelled to try. Many residents are retirees who have sunk their savings into their homes. Now that prices have fallen, they can't get out unless the state buys them out.
Nine Money Island property owners have already requested that.
One is Tony Novak, owner of the local marina. He wants to stay, and thinks he can for the near future, but "there is no doubt that the only reasonable, logical, long-term approach is strategic retreat."
"I have neighbors," he said, "and all they have left in the world is being washed away."
In October, Wren held a forum on what many consider the hot issue for the bay shore: "Rising Tides."
About 100 people went to the nearby hamlet of Bivalve on the Maurice River, and filled a chilly room in a historic shipyard shed owned by the nonprofit Bayshore Discovery Project, which Wren founded.
It owns New Jersey's tall ship, a historic oyster schooner called the A.J. Meerwald, and the walls of the room were lined with vintage oyster cans.
Outside, docks built in the early 1900s still exist, and old-timers notice that the tide comes up higher than it used to.
On the serpentine Maurice River, erosion - a natural process worsened by sea-level rise - has almost cut through the bend at Bivalve. If it occurs, the docks might end up high and dry, and land to the east will flood.
Toward the bay are "ghost forests" - skeletons of trees killed by saltwater intrusion.
Upstream, a quarter century of bird counts shows that black vultures, a Southern species, are becoming more numerous.
In decline are American black ducks, which depend on a freshwater wild rice that is being depleted as saltier water moves up the Maurice River.
"The coast is changing," Jennifer Adkins told the group in Bivalve that night.
The executive director of the Partnership for the Delaware Estuary, she cited research showing the dramatic loss of the bay's wetlands. Nearly 5,000 football fields' worth vanished from 1996 to 2006 alone, mostly from sea-level rise and erosion.
Wetlands protect coastal areas by absorbing water from storm surges, so losing these natural buffers makes the bay shore communities more vulnerable.
And then Matt Blake, then with the American Littoral Society, raised the topic few wanted to hear.
"Strategic retreat," he said. "The questions of whether to pull back or reinforce are going to come up again and again."
He didn't claim to have an answer. But he said solutions should be based on research, not emotion. "We'll never have enough resources to defend every community. Before we start spending on new roads and bridges and pipes, we have to run a cost-benefit analysis."
But Campbell wouldn't hear of it. "There seems to be a double standard between the Atlantic coast communities and the Delaware Bay," the mayor said when he got to the lectern. A murmur of assent rose from the audience.
"I don't hear anybody talking about retreat in Atlantic City," he said. Or "moving the casinos back to Absecon."
Still, he handed out a summary of township problems: collapsed pavement, eroded road shoulders, failing seawalls.
"Downe Township is just one hurricane away from becoming a bayfront statistic" like the three other abandoned towns.
Eleven days later, Hurricane Sandy hit.
Bayfront houses were undermined, the sand washing out from under them. Front steps hung in the air. Decks and front rooms were gone.
Campbell said damage along the bay front totaled $20 million; about 30 homes were destroyed.
"Sandy focused everybody's attention," Wren said. "You can't just quietly ignore [the rising ocean] anymore."
Remote and little clout
The bay shore, unlike the Atlantic coast, is ill equipped to respond.
Cumberland County is remote, rural, and economically depressed, the poorest county in the state.
"They don't have the population. They don't have the tax base. They don't have the votes," said the trust's Eisenhauer. "They don't have the clout to get the funding they get on the Atlantic coast."
Yet the area is hugely vulnerable. About 12 percent of the county's population lives in a floodplain, according to a federal analysis. Ditto 6 percent of the schools, police stations, and other "critical facilities." Plus 10 percent of the road miles.
Local leaders feel they aren't getting much help.
Across the bay, Delaware has a climate-change action plan and a sea-level rise advisory group. It has listed strategies for its bay shore and analyzed the costs and benefits.
"The first step is to have rock-solid science and good economics," said the state's environmental head, Collin O'Mara.
In New Jersey, Gov. Christie closed the Office of Climate Change, although a spokesman said several agencies deal with the issue, and many efforts have been launched since Sandy.
Department of Environmental Protection spokesman Larry Hajna said officials visited Downe "to see what we can do."
"Sea-level rise is clearly one of the biggest concerns along the bay," he said. "But at this point there aren't any long-term answers." Federal, state, and local entities would have to get involved, he said.
Ultimately, the question may not be how to keep the waterfront intact but how to get to the towns in the first place.
A new sea-level rise mapping tool from Rutgers University shows that with one more foot of rise - easily possible before century's end - the roads through the marshes would be underwater at high tide.
Wren thought she would have more time.
She imagined that the changes "would be far enough in the future that I could figure out how to manage it" - maybe by working from home during floods. Not anymore.
She and her husband, Jesse Briggs, subscribe to an alert system for when higher-than-usual tides are predicted.
But in December, an alert went out at 3 a.m. When Wren woke up, it was already too late. Her Prius was swamped. Now, she drives a hybrid SUV that is six inches higher.
She thinks it was hubris for humans to build on the shore. And "it seems like folly to be trying to control nature" now.
But she's lived on the water her whole life. Briggs is captain of the A.J. Meerwald. They named their son Delbay - for Delaware Bay.
"I can kind of see it from all sides," Wren said of the debate over Money Island and its neighbors. So far, it comes down to this: "If the township decides to keep the infrastructure, I'm committed to keeping my house."
Contact Sandy Bauers at 215-854-5147, firstname.lastname@example.org, or @sbauers on Twitter. Her blog is at inquirer.com/greenliving.