Marion County holds first public hearing on proposed Land Development Code amendments focusing on stormwater, flood mapping and landscaping

Marion County officials held the first of two public hearings Wednesday on proposed amendments to the county’s Land Development Code that would change stormwater management rules, update flood-mapping references and add landscaping requirements for drainage retention areas.

The package, presented by County Engineer Steven Cahoon and stormwater engineer Jason Cambry, would exempt certain single-family residences and bona fide agricultural uses from the major site plan process, add permitting steps for driveway culverts, reduce required berm widths from 12 feet to 5 feet in some cases and expand flood-related mapping to include county flood-prone data as well as FEMA maps. Cahoon said the changes also aim to improve the county’s Community Rating System, “a huge benefit to citizens that have to buy flood insurance in the county.”

Jason Cambry, the county’s stormwater engineer, summarized several technical changes: “We have added new categories to exempt single family residents and farms from the major site plan,” and he said the amendments would require an additional inspection when a culvert is installed for a driveway connection. Cambry also said the stormwater quantity standard for open basins would change from a 25-year, 24-hour event to a 100-year, 24-hour event and that the county would adopt NOAA Atlas 14 rainfall data in place of legacy FDOT curves.

David Tillman, chair of the Land Development Regulation Committee, described the package as largely “cleanup language” that formalizes practices staff had been granting waivers for and said several changes were meant to align with water management district criteria. He warned, however, that parts of the landscaping and grading language could conflict with state legislation, saying, “the argument against Senate Bill 180 is that this is something giving you guidance on how to do something properly that didn't exist before.”

A contested item among commissioners was a grading criterion that applies to lots 75 feet wide or less. Tillman said that threshold came from the draft language and from correlation with R-4 zoning and typical building footprints; a commissioner asked staff to review whether 75 feet should be increased to better target problem subdivisions such as some with 80- to 82-foot lots. Cahoon and Tillman acknowledged the threshold may need refinement and directed staff to revisit the number before the next hearing.

A substantial portion of the presentation covered drainage retention areas, or DRAs. Staff sampled a 4.4-acre DRA on Southeast 90 Second Loop and estimated a full code-compliant planting and curb design would cost about $67,000 to construct and establish. Cambry and Cahoon presented three scaled landscaping options for new DRAs or future projects: a high-intensity code-compliant design (roughly 36 shade trees along frontage for the sample site), a medium option (about 9 trees and reduced bed sizes, estimated around $64,000 for the sample) and a low-intensity option (about 9 trees with even smaller beds and wider spacing, estimated at about $33,000). Cahoon noted the Office of the County Engineer currently has no budget to retrofit the county’s roughly 2,500 existing DRAs and that the county engineer could be given waiver authority for site constraints or acquisition limits.

Commissioners asked staff for illustrative overlays and examples showing how the landscaping options would look on actual DRAs and suggested using lower-maintenance species where possible. Commissioner Salic requested that staff work with a county landscape architect to produce overlays and emphasized that in places where right-of-way is wide and unconstrained, modest plantings can improve appearance without large maintenance burdens.

Multiple speakers, including Tillman, cautioned that recent state legislation (referred to repeatedly as Senate Bill 180) limits some local tree-protection and landscaping requirements; commissioners directed staff to continue evaluating the proposed language and to forward the draft amendments to the board for further direction, even if parts may later be revised for legal compliance.

There were no public comments at the hearing. The board announced the second public hearing on the ordinance amendments will be held Sept. 3, 2025, at 5:30 p.m. at the McPherson Campus Auditorium. No formal vote or adoption occurred at the August 13 hearing; staff will revise language and return for the second hearing.