South Haven was a resort town built on sunsets. The kind of place where the entire economy ran on people driving three hours to watch the sun go down over Lake Michigan and then buying fudge. It was charming. It was seasonal. It was exactly the kind of economy that does not survive climate destabilization, lake-level rise, and the collapse of the middle class that used to fund weekend getaways.

What South Haven became is harder to categorize. The old downtown -- what's left above water -- has been repurposed as an offshore recreation zone for mid-tier corporate workers from the GLMZ corridor. Tessera Leisure Holdings operates the beachfront, offering 'authentic lakeside experiences' to employees who earn enough to afford a weekend pass but not enough to access the elite resorts further north. The experience is manufactured nostalgia: reconstructed beach cottages, artisanal ice cream that costs more per scoop than the original shops charged per gallon, and sunset viewing decks with augmented reality overlays that filter out the cargo platform traffic on the horizon. It is a theme park version of a place that used to be real.

Below the tourist layer, the Undertow earns its name. The lake has risen nearly two meters since South Haven's resort heyday, and the lower sections of the old town are permanently flooded. This submerged district -- locally called the Undertow -- is where the people who actually live here year-round have settled. Houseboats, converted marina structures, and floating platform homes connected by walkways and rope bridges. The Undertow community is small, insular, and deeply suspicious of outsiders. They fish the lake, maintain their own power grid from wave-energy converters, and operate one of the most effective smuggling networks on the eastern shore. Cargo that enters the lake from offshore and needs to reach the inland corridor without passing through any checkpoint goes through the Undertow. The residents don't advertise this. They don't need to. Everyone who needs to know already does.