Iberia Parish consultants recommend detention ponds and Far Canal cleanup in $12M flood‑mitigation plan

Iberia Parish officials and consultant engineers on Thursday outlined a planning‑level flood‑mitigation recommendation for the T‑Bayou watershed that combines multiple upstream detention ponds with cleaning and selective widening of Far Canal, a package consultants said would substantially reduce frequent flooding in parts of the watershed.

Parish President said the council chose a comprehensive study after last year’s damaging floods and is seeking funding partnerships to implement a large‑scale solution: "We're looking in the neighborhood of $12 million," the Parish President said, adding the project is intended to protect broad areas, not only individual houses.

Consultants described the work that informed the recommendation: updated topographic surveys and bridge inventories, higher‑resolution lidar and 2025 land‑cover inputs, and a switch from older DOTD rainfall values to NOAA Atlas 14 rainfall depths to reflect more intense modern storms. They also tested downstream tailwater conditions and reported no change was needed to the assumed downstream boundary for the model runs presented.

The study analyzed more than a dozen scenarios grouped into three types—channel improvements (widening or regrading), a diversion to Bayutesh near Emil Verrett, and upstream storage ponds—both alone and in combinations. The recommended package paired upstream ponds with cleaning of Far Canal; the consultants reported the evaluated ponds would provide more than 200 acre‑feet of storage across roughly 25 acres, and that the combined scenario would remove inundation over roughly 500 acres for a 10‑year storm. They also reported a maximum modeled local water‑surface reduction of about 14 inches at some upstream cross sections.

Consultants emphasized tradeoffs: widening channels can produce larger local reductions in some spots but is constrained by limited right‑of‑way, buried utilities and nearby property; ponds can be sited in open fields (including cane fields identified in the model) with smaller property impacts but require land acquisition and farmer cooperation. A feasibility‑level analysis, the consultants said, would refine pond footprints, control structures and outfall designs and would validate that any increased conveyance does not overload downstream systems.

Members of the public and one consultant who worked on earlier T‑Bayou work noted historical precedent: Dax, who identified himself as with Fence Maker, said earlier cleanings and detention ponds have reduced flooding in nearby Youngsville and argued the combined approach has proven benefits, while cautioning that ponds are not a "cure all" where subdivision‑scale drainage systems or clogged local pipes remain problematic.

Consultants and officials listed next steps: secure funding, perform feasibility and engineering design (including benefit‑cost and downstream impact checks), acquire property or servitudes where needed, update parish drainage ordinances and then proceed to construction if funding and feasibility are confirmed. Officials also said updated model results would be used to update FEMA base‑flood mapping, which can change local insurance premiums and construction guidance.

Cost, timing and limits

Consultants estimated the recommended ponds plus Far Canal cleaning package at roughly $12–12.5 million for the ponds and canal work; that estimate does not include any large‑scale work at Lake Dotrie or substantial downstream structural projects such as levees or major pumping installations. Speakers warned that larger regional measures—dredging or building levees—would be a separate, far costlier undertaking and that local projects would not eliminate risk in an extreme "perfect storm" or coastal‑driven tailwater event.

Questions from residents raised specific concerns about an S‑curve location that has repeatedly caused local flooding, the capacity of local road/ditch inlets and the presence of a force main and lift station near the channel. Consultants acknowledged those constraints and said design work must address utility conflicts and right‑of‑way acquisition; they also noted that dry detention ponds would store runoff temporarily and discharge it via low‑level outlets to relieve the channel during frequent storms.

What happens next

Officials said the parish will pursue funding and recommended the parish begin a feasibility level analysis and a drainage master plan to update ordinances and design standards. Consultants and officials will be available after the presentation for one‑on‑one questions, and staff indicated they would coordinate follow‑up briefings and the ordinance work needed to hold new development to updated drainage standards.

The meeting closed with thanks from the Parish President and an invitation for additional public comments during the open‑house portion.