There were a few librarians working on answering this question. The following are their answers, listed by number.

1. I checked US Code on GPO Access, using "Emergency ADJ Personnel," came up with documents relating to disaster relief, but nothing addressing the issue of entry into private homes.

2. Looked at Lousiana State Law found the following: it suggests that there are times that the authorities can go as far as taking property if they "need" it. anyone out there a law librarian?

RS 29:726
§726. Office of homeland security and emergency preparedness; authority and responsibilities

A. The Military Department, office of homeland security and emergency preparedness, under the governor and the adjutant general, shall be responsible for homeland security and emergency preparedness in the state. In order to perform the duties and functions required under this Chapter, the department may establish and maintain office of homeland security and emergency preparedness operations centers. The department may obtain immovable property for such operations centers by sale, transfer, grant, donation, lease, exchange, or any other means, including interagency transfers of property and cooperative endeavors.

3. Got this from another listserv.

"Dear Friends:

Thanks to you many who are working with the Katrina
evacuees. Here is a resource for law of LA and TX
for basic rights. Please forward this on to pro bono
efforts, legal services lawyers, and any person or
group who is reaching out in solidarity with all of us
in need."

From: http://law.loyno.edu/probono/clinic/