A map drawn in 1949 by a Charleston lumber executive and city alderman is getting fresh attention from researchers and preservationists who say it still predicts, with uncanny accuracy, where the peninsula floods worst today. Alfred O. Halsey spent years tracing how Charleston's shoreline had shifted since the 1600s, and the resulting document now functions less like a historical curiosity and more like a flood-risk forecast for a city facing hundreds of millions of dollars in drainage and seawall work.
Halsey, who served as a Charleston city councilman while running a lumber company, produced his visually distinctive map of the peninsula in 1949, according to research published in a Springer journal. The map was first published in the November 27, 1949 issue of The News and Courier, per records held by the South Carolina Historical Society. Those same historical society records describe a Halsey map superimposed on a 1946 city engineers map drawn by Joseph Needle, while the Historic Charleston Foundation has separately stated that Halsey created his work, titled Historic Charleston on a Map, in 1939 — an account that differs from the historical society's dating. Whatever the precise timeline, Halsey is credited with having studied Charleston's development for roughly a decade before compiling the finished work, according to the 1949 article cited in the Springer research.
The map compared historic surveys dating back to 1680 against the city's footprint in 1949, outlining the pre-colonial boundary of the peninsula against its later, much larger shoreline. It shows where creeks had been filled, where battles were fought, and where history unfolded on ground that didn't always exist in Charleston's earliest days, the Springer research notes. Per that same research, the 1949 article reported that Halsey's map showed noticeable settlement already occurring in the filled areas, and Halsey himself observed that made land was likely to flood increasingly over time as it continued to settle.
Why So Much of the Peninsula Is Built on Fill
Charleston's original settlers built on the highest ground available — just 62 acres on an otherwise marsh-riddled peninsula, according to the Historic Charleston Foundation. Everything else was water, swamp or tidal marsh that generations of residents gradually filled in with ballast, trash and construction debris. Today, the foundation reports, at least a third of the peninsula sits on that made land.
Sarah Platt, an archaeologist at the College of Charleston, said the city has been caught in cycles of land filling and its consequences for a long time.
The city's own Hagood Avenue corridor illustrates the pattern starkly. Hagood Avenue and the areas west of it were constructed atop a former municipal dump that operated until the 1970s, ultimately absorbing an estimated 1.5 million tons of waste, according to the Post and Courier. Charleston filled roughly 1,000 acres of marsh along the Ashley River, and the area now includes Joseph P. Riley Jr. Park, the Charleston Police Department and the WestEdge development. The newspaper's reporting notes that fill-and-build zones like this one are now among the first and worst spots in Charleston to flood during king tides or heavy rain.
What the Map Leaves Out
Halsey's map isn't without blind spots, and researchers studying it are direct about what's missing. The map contains Lost Cause ideology, reframing the Civil War as a fight over states' rights rather than slavery, per the Springer research, and it omits local Black history altogether — even though much of Charleston's low-income housing was built during Halsey's own lifetime, often on the same made ground the map charts so carefully.
Doug Rivet, an urban geographer at the College of Charleston who leads the Spatial History of Charleston project, is working on what amounts to a modern counterpart to Halsey's work, one explicitly aimed at including the voices the original map left out. The project layers personal narratives, historical documents, census data and other material into a more complete picture of the city's past, drawing on an approach the Charleston Library Society describes as deep mapping — digital maps that integrate spatial, historical, cultural and environmental data for public use. Rivet has said the project is intended to endure beyond his own lifetime.
Anna-Catherine Alexander, director of advocacy initiatives for the Preservation Society of Charleston, said the Halsey map still effectively communicates modern climate risk and hazard vulnerability, even decades after it was drawn. She added that Charleston has made some progress in confronting its flood risk but still has farther to go. Historical precedent backs up the map's warnings: the 1886 Charleston earthquake prompted a U.S. Geological Survey report finding that destruction was generally greater on made ground than on the city's original higher elevations, with some exceptions.
Charleston's Flood Response
The city is pursuing projects to safeguard its most flood-vulnerable areas, many of them the same filled-in neighborhoods Halsey flagged generations ago. The largest piece is the Battery Extension, which could receive a sizeable portion of its funding from a county Transportation Sales Tax referendum if County Council approves sending the measure to voters in November, per the Post and Courier's reporting on the project's financing. The Army Corps of Engineers has awarded $6.2 million in design contracts for the project's two sections, which run from Adger's Wharf to Lockwood Drive along the Ashley River and are being engineered to keep stormwater off the peninsula while remaining usable for residents, workers and visitors, according to Live 5 News.
Closer to the old dump site, the Hagood Improvement Project is aimed at reducing corridor flooding, improving pedestrian and cyclist access, and adding new flood-controlling green space.
Charleston has a long history of filling creeks and holding back the ocean, alongside calls for residents to learn to live with water. The plan predicts sea levels will rise roughly one foot over the next 25 years, a projection that lines up with separate Post and Courier reporting showing Charleston's sea levels have already climbed about a foot over the past century, with another foot of surge forecast by 2050.
Middle-range projections cited by the newspaper put ocean rise at two to six feet by the end of the century, a range that frames just how high the stakes are for a city built largely on fill. Nearly eighty years after Halsey traced the contours of Charleston's filled creeks and settling marshland, his map keeps pointing planners back to the same vulnerable ground.
