Most of the time, the windowless building with the dome-shaped roof will be a typical high school gymnasium filled with cheering fans watching basketball and volleyball games.

But come hurricane season, the structure that resembles a miniature version of the famed Houston Astrodome will double as a hurricane shelter, part of an ambitious storm defence system that is taking shape along the Texas Gulf Coast.

Its brawny design — including double-layer cinder-block walls reinforced by heavy duty steel bars and cement piers that plunge nine metres into the ground — should allow it to withstand winds up to 320 km/h.

"There is nothing standard" about the building, said Bob Wells, superintendent of the Edna school district, as he stood inside the $2.5 million US gym, which is set to be completed by March. "The only standard stuff is going to be the stuff we do inside."

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The Edna dome is one of 28 such buildings planned to protect sick, elderly and special-needs residents who might be unable to evacuate ahead of a hurricane. First responders and local leaders will also be able to take refuge in the domes, allowing them to begin recovery efforts faster after a storm has passed.

Storm defence structures are getting increased attention in the aftermath of Hurricane Sandy, which inflicted heavy damage on the East Coast in October. The city of New York, for instance, is considering a multi-billion-dollar system of sea barriers.

Multi-purpose use of domes

For Texas, a state always in danger during hurricane season, the domes offer the extra benefit of serving as recreation or community centres when not needed as shelters. They are being erected with help from the U.S. Emergency Management Agency.

"I think it's good for FEMA, and I think it's good for us. And I think it's good for the taxpayers," Wells said.

The gym in Edna, a town of 5,500 people southwest of Houston, is the second hurricane dome in Texas. The first was built in 2011 in Woodsboro, near Corpus Christi. Most of the domes will be around 1,850 square metres.

The plan calls for structures in 11 counties in the Rio Grande Valley, around Corpus Christi and along the coast from Victoria to Newton counties, said Tom Vinger, a spokesman for the Texas Department of Public Safety.

The $2.5-million US Edna hurricane dome, which will also double as a high school gym, is one of 28 structures being built in Texas to shelter residents in the event of a major storm. (David J. Phillip/Associated Press)

So far, $34.5 million has been awarded. This month, FEMA approved funds for a hurricane dome that will serve as a community centre in Brownsville, one that will serve as a wellness centre and physical rehabilitation facility in Bay City and two that will serve as multi-purpose training centres in Kingsville.

Inside the gym in Edna, Wells' voice echoed as he pointed to the ceiling, which has layers of sprayed-on concrete, insulation and rebar, all of which are under a heavy duty fabric that gives the structure its distinctive wind-resistant shape.

The doorways are covered by awnings of heavy gauge metal and supported by concrete girders that go 4.5 metres into the ground.

FEMA helps fund structures

FEMA is paying for 75 per cent of the dome structures, with local communities picking up the remaining cost.

The funding is part of the agency's initiative to help homeowners and communities build hardened shelters that provide protection from extreme weather.

Nationwide, more than $683 million has been awarded in 18 states, including Texas, Alabama, Michigan and South Carolina.

Walking around the gym, Wells said it reminded him of when, as a teenager, he first walked into the Astrodome after it opened in 1965.

"It was like, 'Oh, wow, this is so cool,"' he said. "I'm still kind of in the 'oh, wow' stage with this."