Stormwater Special Assessment

Special assessments are used by many local governments throughout Florida to assure that this essential service is adequately funded. Unlike a tax, a special assessment must be developed to recover each property’s proportionate share of the costs and can only be used to fund those services.

Hardship assistance is available for eligible residents.

Stormwater Assessment Resolution and Supporting Documentation

Stormwater Assessment Rates and Assistance (as of Oct. 1, 2026)

Rate per 1 ERU (Equivalent Residential Unit): $150.65 (one ERU is the equivalent of 2,300 sq. ft. of impervious area)

Properties charged on a fixed-rate basis

  • Single-family: 1 ERU (plus 1 ERU per accessory dwelling unit/ADU)
  • Duplex: 2 ERUs
  • Mobile home: 0.6 ERU

Properties charged on a measured square-foot basis

  • General property (condominiums, apartments, commercial, mobile home parks, mixed-use)
  • Number of ERUs = total square feet divided by 2,300

Stormwater Assessment Frequently Asked Questions

What is the purpose of the special assessment for stormwater services?

It provides a dedicated and equitable funding source for the cost of providing stormwater services. Developed properties contribute stormwater runoff into the city’s stormwater system, which is comprised of a network of pipes, culverts, ditches, storm drains and detention basins designed to collect and treat stormwater runoff. It is estimated that the city will collect approximately $10,706,488 from the Stormwater Services Assessment.

How is the assessment calculated?

Each parcel of developed property is assessed based upon the estimated amount of stormwater runoff generated by impervious and semi-impervious area on the property. Impervious area includes buildings, parking lots, driveways, patios, decks, walkways, and athletic courts. Semi-impervious area includes land surfaces that partially restrict the penetration of water, such as porous concrete and asphalt pavements, gravel, lime rock and certain compacted soils.

What is an ERU?

The amount of impervious and semi-impervious area is expressed in terms of ERUs (equivalent residential unit). One (1) ERU is defined as 2,300 square feet of impervious area. Generally, the number of ERUs for each property is calculated by dividing the impervious area by 2,300 square feet.  However, certain property types are assigned a fixed rate regardless of how many square feet of impervious area they have.

What are the property types?

  • Fixed-rate classifications: Single-family, duplexes, mobile homes
  • Measured impervious area classifications: General property (condominiums, apartment complexes, mobile home parks, commercial and mixed-use)

Truth In Millage (TRIM)

The annual TRIM brochure is included in the mailed TRIM notices to property owners by the Alachua County Property Appraiser.

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