Ridgeland's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Ridgeland is Category C. Moderate seismic hazard. Code adds irregular-building restrictions and requires bracing of some nonstructural components (e.g. tall shelving, water heaters) in addition to structural detailing. Rank it against the rest of the country and Ridgeland sits at the 67th percentile for seismic hazard among 4,875 US cities.

Where Ridgeland sits in Mississippi

USGS's underlying values for Ridgeland: 0.07g peak ground acceleration, 0.146g at short period, 0.086g at 1 second. Within Mississippi alone, Ridgeland ranks 33 of 61 cities by seismic hazard - the 47th percentile in-state. Ridgeland has a population of about 24,576.

Retrofit economics for Ridgeland

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by Mississippi specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in Mississippi.

Insuring against this, not just retrofitting

A Ridgeland homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where Ridgeland's figures come from

Ridgeland's Category C and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category C does and doesn't tell you about Ridgeland.