ROBERT SIEGEL, HOST:
Earthquakes are common in central Italy. As we heard, an earthquake devastated the nearby city of L'Aquila back in 2009. That event prompted tougher building codes for new construction. But as NPR's Jon Hamilton reports, many beloved older buildings in the region remain vulnerable.
JON HAMILTON, BYLINE: Whenever a big earthquake shakes the mountainous spine of central Italy, old buildings collapse. Paolo Bazzurro, a professor of engineering at the university in Pavia, says this latest temblor is just one more example.
PAOLO BAZZURRO: This is not a surprise. It is sad to see that anytime it happens, we have a lot of casualties due to poor buildings essentially.
HAMILTON: Bazzurro says the most recent buildings made of reinforced concrete usually do fine.
BAZZURRO: But the old building stock, the buildings that have been there for tens of years or hundreds of years in this case - there is hardly anything you can do.
HAMILTON: Those buildings are usually unreinforced masonry structures, and Bazzurro says they were built long before any building codes existed.
BAZZURRO: We could of course in theory retrofit all the buildings, but that's more theoretical than practical.
HAMILTON: Engineers learned that after the 2009 earthquake in L'Aquila which killed more than 300 people and leveled the city's historic downtown. Since then there has been a lot of talk about reinforcing old structures that survived and restoring badly damaged buildings in a way that would protect them from future earthquakes. But Alessandro Martelli, president of the Italian Association on Anti-seismic Systems, says there hasn't been much progress.
ALESSANDRO MARTELLI: We are talking and talking and talking but not in a very useful way.
HAMILTON: Martelli says one big problem is cost. Most community simply aren't willing to invest in their historic structures to protect them from future earthquakes.
MARTELLI: When I'm talking about retrofitting existing buildings, the answer is usually, we have no money for that.
HAMILTON: Of course once a building has been damaged or destroyed, the cost is a lot higher. Martelli says that leaves communities like L'Aquila with a tough choice.
MARTELLI: They have to decide which structures should be saved, and the rest should be, my opinion, demolished. You cannot save everything.
HAMILTON: But many residents just can't accept that, and the result is not much happens. Mary Comerio is president of the Earthquake Engineering Research Institute and a professor at the University of California, Berkeley. She visited L'Aquila soon after the 2009 earthquake and has returned several times since then.
MARY COMERIO: One of the difficult lessons - and this is generally true in Italy - is that there's a lot of delay in any kind of recovery because of the kind of arguments over what to do with the historic structures.
HAMILTON: Comerio says she checked on the progress in L'Aquila just a couple of years ago.
COMERIO: They have just begun some rebuilding on really the furthermost outside streets of town, but the historic center is untouched. It's just empty and dead.
HAMILTON: Comerio says she hopes villages struck by this latest earthquake can find a better solution. Jon Hamilton, NPR News. Transcript provided by NPR, Copyright NPR.