The activists also protested the latest deadline for evicting about 5,000 residents living in FEMA trailers, the McClatchy News Service reported.
"The people of the Gulf Coast don't want FEMA trailers," Michele Roberts of the Advocates for Environmental Human Rights said Monday. "They want to rebuild homes."
FEMA backed off the May 30 eviction deadline while one protester said, "A dry roof over a toxic trailer beats no roof at all," referencing the discovery that FEMA trailers were laced with formaldehyde.
"FEMA is continuing to work with federal, state and local partners to help area residents make the transition to long-term housing," FEMA spokesman Clark Stevens said. "New options are being finalized in the next few days, and no one will face eviction from a temporary unit while transition measures are implemented."
The coalition challenged President Barack Obama's administration to make improvements by Aug. 29, the fourth anniversary of Katrina's devastating march through Louisiana and Mississippi, McClatchy reported.
"This is President Obama's Gulf Coast now, and nothing has been done yet to remedy the government's failures," Roberts said.