GONZALES — The Ascension Parish Council has enacted up to a six-month ban on the use of dirt to raise new homes and businesses across more than 70 percent of the low-lying parish.

Parish officials said the resolution, passed Thursday, takes effect immediately. It will exist only until the parish finishes drafting and adopting a new floodplain management ordinance that has been under development by a closed-door committee for several weeks, and for a period no longer than six months if an ordinance isn't adopted.

Council Chairwoman Teri Casso told her fellow council members Thursday night that the current schedule for the new ordinance would have it on track for a possible final vote Sept. 5.

"All of you know that I have never supported a moratorium of any kind, any shape in Ascension Parish. Tonight, I am," said Casso, a businesswoman and former restaurateur.

Casso said the moratorium was needed to protect the parish's "fragile floodplain" while the ordinance is finished. Other council members who supported a stronger fill ordinance have called for the moratorium to force the council to act on the politically difficult measure. 

Called for by Parish President Kenny Matassa, the floodplain ordinance committee has been meeting in secret since June, shortly after the council sustained his veto of an earlier version of the ordinance in late May.

That ordinance proposed absolute limits on fill with mitigation, with mitigation exceptions for smaller lots, and proposed raising the minimum height to which new homes, business and other structures must be built.

The upshot of those rules was that many homes in the lowest areas would likely have to be built on piers, a prospect builders said would raise costs prohibitively and run against market preferences for slab homes. 

On Thursday, Matassa read the council a letter that said the committee has been "invaluable in helping to determine a critical component in the future development of Ascension."

While Matassa stated his preferences for the future ordinance that required only mitigation of fill in all but the very lowest areas — the coastal zone — he also committed not to veto what the council passes and to work to enforce that law once it passes.

"I will support any decision made by the Council regarding the minimum height above BFE (base flood elevation) and the maximum amount of fill," Matassa said. "I have also directed my administration to create a fill permit that adheres to all of the requirements of the flood management ordinance."

The base flood elevation is the projected height of water in a 100-year flood and is a benchmark figure in the nation's flood insurance program.

Ascension now requires that homes be built 1 foot higher than the base flood elevation, but the flood ordinance Matassa vetoed called for new structures to be 2 feet higher.

The new moratorium applies to all land that is not in the "X" flood zone on the Federal Emergency Management Agency's flood insurance rate maps. The land affected includes all property in any of the "A" flood zones, or those deemed the most at risk of flooding by FEMA.

These are the properties subject to the 100-year flood or floods with an even more prevalent risk. A 100-year flood has a 1% chance of happening in a given year. 

In Ascension, more than 70% the land in the parish falls in this category, according to the Amite River Basin Commission. The areas along the Amite River and near the swamps that feed the Blind River fall heavily in this category, including in the Sorrento, St. Amant and Lake areas but also parts of Prairieville and Gonzales.

The "X" flood zone applies primarily to land subject the 500-year flood or even lower risk floods. A 500-year flood has a 0.2 percent chance of happening in a given year.

The moratorium and apparent momentum on a new fill ordinance comes as the council and administration have been responding to renewed scrutiny of their fill practices since the August 2016 flood.

Homeowners complained new neighborhoods raised up on several feet of dirt to meet federal and parish elevation requirements were pushing water on their older, lower homes. Builders and their engineers countered that their use of detention ponds to mitigate the effect of the piled up dirt was not making flooding worse on neighboring properties.

The proposed ordinance has been a point of contention in the parish for more than a year after the parish's paid consultants, HNTB, brought forward recommendations in mid-2018 that called for limits on fill.

Councilman Randy Clouatre, whose low-lying St. Amant district flooded heavily in 2016 but also has many homeowners using fill, crystallized on Thursday how the political conflict plays out for council members, as he called for the administration to enforce the moratorium fairly.

"I represent the person that's digging the pond (to gather dirt and raise the land) and I represent his neighbor that thinks he's flooding him," Clouatre said. "Alright, so we need something laid out, even, across the board."

Matassa promised as much and said he would direct the parish's many crews on the road daily to be on the lookout for new fill once the moratorium is in effect.

Some council members have been more ardent supporters of stricter limits on fill and asserted the fill ban would be temporary, not interfere with commerce and not prevent people from building on or selling their land. 

"Failing to approve this temporary ban and a subsequent fill ordinance will send a clear message to some homeowners that their right not to be flooded by future development is secondary to those that wish to allow development without regard for their neighbors," Councilman Aaron Lawler, who has pushed for fill moratoria in the past, said in a statement.

What exactly will come out of the secret committee is not yet clear.

In his letter, Matassa advocated for the standards he supported in his veto message: no fill limits in any areas outside the coastal zone with zero net-fill mitigation, but a ban on fill inside the coastal zone.

The zone falls inside the 100-year flood plain but covers lightly populated lowlands closest to the Amite River and inside the McElroy Swamp. He said a permanent fill ban in that area was a consensus reached by the committee.

Parish engineers are expected to make presentation to the council Aug. 1.

Email David J. Mitchell at dmitchell@theadvocate.com

Follow David J. Mitchell on Twitter, @NewsieDave.