Thousands of U.S. citizens have been left homeless in the wake of Hurricane Katrina's deadly wrath. There are many potential housing solutions for the evacuees, but one architect's plans go back in time several centuries.

At the Cal-Earth Institute in Heserpia, California, the houses are made of mud. Nails and wood are nowhere to be found. The houses -- using dirt, water and some barbed wire -- are essentially built from the earth. The Cal-Earth Institute is the brainchild of architect Nader Khalili.

"It can be built anywhere in the world by using the earth right under your feet."

The houses are built by placing earth into long bags, winding them into a coil and them bonding them with barbed wire. The structures are then pounded into place.

architect Nader Khalili

Khalili has received some interest from the gulf region where Hurricane Katrina has left thousands homeless. His structures could provide immediate shelter for evacuees.

"A structure like this is an emergency shelter that could be put together in one day or two days," he says.

The dome shaped structures are also very stable. They passed California's seismic codes and Khalili believes they could easily survive a hurricane.

The group has also built larger structures meant for long-term housing by adding a little cement to the mixture. Khalili says these structures would last for centuries.

Khalili has not heard from FEMA [Federal Emergency Management Agency] about building shelters for the Hurricane Katrina victims, but he questions a traditional rebuilding process.

"Building all that area, the whole forest would have to be cut to build those wooden houses again; that just like matchsticks would fall apart again in the next hurricane."

The National Aeronautics and Space Administration (NASA) and the United Nations have also expressed interest in Khalili's work.