Port Jefferson, NY: what USGS's seismic model says

Under the seismic model IBC and ASCE 7 use for new construction, Port Jefferson is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Nationally, Port Jefferson ranks above 58% of the 4,875 cities in this dataset for seismic hazard - the 58th percentile.

Port Jefferson by the numbers

The raw figures: peak ground acceleration 0.109g, short-period spectral response 0.194g, 1-second spectral response 0.051g. Among 170 New York cities in this dataset, Port Jefferson ranks 100 for seismic hazard, the 41th percentile within the state. About 8,189 people live in Port Jefferson, New York.

Retrofit economics for Port Jefferson

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for New York. A typical retrofit still runs $5,000-$10,000 nationally, about $7,000 for a common single-family job.

What this means for insurance

Outside California, earthquake coverage is typically sold as an endorsement added to a standard homeowners policy, not a separate product - worth asking about directly when getting a home-insurance quote for a Port Jefferson address.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced Port Jefferson's numbers. The guide to what a Seismic Design Category actually means covers why a category is never a substitute for an engineer's assessment of one specific house.