The severe rainstorms that flooded homes and businesses in south Louisiana last week might not have caused enough damage to trigger federal aid, said homeland security officials from several parishes.

Damage assessments are still underway, but there has to be at least $6 million in damage statewide to meet Federal Emergency Management Agency thresholds for public assistance, which helps local governments repair damaged public buildings and pays for debris removal.

“I’m not very confident that we’re going to meet that threshold to get … federal assistance,” Rick Webre, Ascension Parish’s homeland security director, told East Ascension drainage officials Monday.

The band of storms that ripped across south Louisiana last week dumped double-digit rainfall in a 24-hour period, causing flash flooding and inundating homes, schools and businesses. While floodwater has receded, waterways remained closed in Ascension, St. James and Livingston parishes at least until Thursday morning.

In Ascension, rainfall between 10 p.m. May 27 and 3 p.m. May 28 was 10 to 15 inches, parish officials said. The totals approached or exceeded a 100-year event for rain in a 24-hour period in Ascension, according to Natural Resources Conservation Service standards.

Communities like Aben and St. Jude on Ascension’s west bank and Darrow, including the Astroland subdivision, on the east bank were hit especially hard.

In St. James Parish, Lutcher, Gramercy and Paulina had house and business flooding while, in northern Assumption, Belle Rose, Paincourtville and Plattenville received the worst rain.

FEMA requires minimum damage levels at the parish and statewide levels for an event to prompt public assistance. Some parish officials said they were confident the threshold for damage would be met at the parish level but were uncertain whether the threshold would be met for statewide damage.

Webre said the damage in Ascension will greatly exceed the $327,000 threshold for that parish, although it is far from certain that the statewide threshold of $6 million would be met.

Homeland security officials in St. James and Assumption parishes offered similar assessments.

“I know for a fact we definitely will meet the parish threshold number,” said Eric Deroche, St. James Parish director of Homeland Security and Emergency Preparedness. “The question is between us and Ascension and all, will we have enough to meet the (state) threshold number.”

Mike Steele, Governor’s Office of Homeland Security and Emergency Preparedness spokesman, said the agency will have a better idea about federal help at the end of the week.

“We’re working with FEMA to determine exactly what assistance will be available,” Steele said.

While parish homeland security officials are not expecting federal aid to help with cleanup and repairing damaged public buildings, the potential for federal aid to individuals for rental, lodging and other expenses is less clear.

In Ascension, early estimates put the number of homes, businesses and other buildings flooded or damaged at 90 to 120. In St. James, the number of flooded homes and businesses is about 130 while in Assumption the number was about 25, emergency officials said.

Webre said he is working with United Way and local nonprofit group Volunteer Ascension for a grant to help people.

“It’s not going to be a very big grant, but they’re going to do the best we can.”

In Ascension, the flooding and the government response have angered residents, exposed problems in the parish drainage system and led to calls for improvements big and small, including a new seventh pump at the Marvin J. Braud Pumping Station in McElroy Swamp.

Brittany resident Ronnie Bourgeois complained the parish should clear blockages on a bridge that serves his home and crosses Bayou Conway, a key drainage route.

“I think it’s time we break open our piggy bank somewhere and get the permit,” Bourgeois told East Ascension drainage officials Monday.

The Marvin Braud station, which drains a 76-square-mile swath of St. Amant, Gonzales and Prairieville within the Ascension Parish levee system, ran all six of its pumps for 74 hours straight and handled the 15 inches of rain that fell in drainage area. The sixth pump was finished just a year ago in a $13.3 million project on the station first completed in early 1990s.

There were calls this week for a seventh Marvin Braud pump.

“If one of those (six) pumps would have went down, we would have really had a problem with rising elevation within our levee system,” Bill Roux, East Ascension drainage director, told officials Monday.

Follow David J. Mitchell on Twitter at @NewsieDave.