Long Island Sound, NY/CT · $95B (proposal)
LIS-3 · Long Island Sound East-End Ingress Block
A pylon-and-shear-pin barrier between Orient Point and Plum Island that would block high-velocity Atlantic surges from racing down the Sound, while letting normal tides pass. The idea is to turn the Sound's narrow eastern throat into a shock absorber.
Pros
- The chokepoint geography is ideal — a short span does the work of a much longer barrier elsewhere.
- Pre-cast concrete pylons are a mature, well-understood technology with decades of marine track record.
- Protects the entire Connecticut and Long Island north-shore coastline with a single intervention.
Cons
- Seasonal North Atlantic storms would repeatedly halt barge work, stretching construction timelines.
- Two million tons of titanium shear pins is an absurd materials spec — titanium at that scale has no supply chain.
- Blocking surge energy at one end redirects it; the physics of where that energy goes needs serious modeling.
Feasibility: The concept is sound but the materials spec is fantasy. Real surge barriers use steel and concrete, not millions of tons of titanium — global titanium production is under 10 million tons per year, nearly all committed to aerospace. Re-spec with conventional materials and the price drops dramatically, but the proposal as written can't be built.
Aerial mock-up: A stark linear wall visible only as low-profile reinforced concrete caps connecting the two landmasses, allowing normal tidal exchange while blocking sheer wave velocity.
