Seminole County commissioners on Jan. 13 accepted final basin study reports for Lake Monroe/Lockhart Smith Canal and the Big and Little Econahatchee basins, after staff described updated hydrologic modeling that increases the county's mapped 100‑year floodplain in those basins.

Joseph Fafaso, chief design engineer for Seminole County Public Works, said the updated modeling raises the Lake Monroe 100‑year inundation mapping from 6.9 square miles (based on older FEMA maps) to 8.7 square miles—an increase of 26%—and increases the combined Big and Little Econahatchee modeled 100‑year floodplain from 15.9 to 23.3 square miles, an increase of 47%. Fafaso said the differences reflect updated data and model improvements; he noted the current FEMA maps are dated (2007 maps based on 2001 or earlier data) and that the county’s new models identify flood‑prone areas not currently on FEMA maps.

Staff presented conceptual improvement projects derived from the basin studies: the Lake Monroe study identified 15 project concepts (four of which have water‑quality benefits) and the Econahatchee work identified 16 concepts. Fafaso said the basin projects will be scored and then amalgamated into a countywide stormwater master plan and re‑ranked for prioritization and the five‑year work program.

The board moved, seconded and unanimously approved staff’s recommendation to accept the two basin studies into county service. As next steps, staff will provide the models to development review as the latest available data and will submit the final approved studies to FEMA for potential FIRM map updates. Commissioners asked about coordination with cities; staff said Oviedo and Winter Springs have largely completed their city‑level studies and the county has coordinated with municipal staff but has not yet initiated joint construction projects.

No funding decisions were made at the meeting; acceptance is a planning action that allows the county to use the models for permitting, prioritization and FEMA submissions.