Stormwater Program

Hillsborough County’s Stormwater Program provides for the maintenance, rehabilitation, and construction of the public stormwater conveyance and storage systems to address:

  • Safety – elimination of flooding on County roadways based on a 25 year storm event. These projects include the replacement of failed pipes and improved roadway drainage systems by cleaning/grading, adding pipes, and rerouting drainage.
  • Asset Preservation – routine inspections, maintenance, rehabilitation and replacement of infrastructure; repair of structures, replacement of failing pipes, slip-lining and routine cleaning.
  • Regulatory Compliance – response to Federal and State requirements and standards by maintenance and system improvements in surface water detention and retention, treatment, education/outreach, inspections and monitoring/reporting; includes programs such as Adopt-a-Pond, Adopt-a-Stream, outreach to schools and other organizations.

Our residents benefit by having reduced flooding of roadways and improved surface water quality. In addition to reduction of flooding, projects implemented through the County’s stormwater program directly contribute to improved water quality in fresh water wetlands and the improved water quality of Tampa Bay.

Stormwater Program Funding

The Stormwater Program relies on two primary sources of revenue: 

  • the Unincorporated Ad Valorem Assessment, utilized for maintenance and operations, 
  • the Stormwater Utility Assessment (Stormwater Fee), used to fund capital projects and respond to regulatory activities.

Historically, the Ad Valorem and Stormwater Assessments have been leveraged with non-reoccurring supplemental funding to include:

  • Community Development Block Grants (CDBG)
  • Cooperative Funding Agreements with the Southwest Florida Water Management District (SWFWMD)
  • Florida Department of Environmental Protection Grants
  • Federal Emergency Management Agency Grants
  • Community Investment Tax (CIT)

Stormwater Fee

The Stormwater Utility Assessment (Stormwater Fee) that all property owners in unincorporated Hillsborough County pay annually funds drainage projects to improve shared public facilities. These projects include the replacement of failed pipes, improvement to roadways drainage systems, and water quality improvement projects and programs.

The Stormwater Utility Assessment period is January 1 through December 31 (calendar year) and is assessed in arrears (toward the end of the calendar year the assessment covers).

The assessment varies depending on the type of property. See below for current rates:

Calendar Year 2023 (Resolution No. R-23-068)

Property Classification Building Footprint (total gross area in square feet) Assigned ERU 2023 Annual Stormwater Assessment
Single Family
100 - 1,500 0.55 per dwelling unit $47.57
Single Family
1,501 - 3,200 1.00 per dwelling unit $86.49
Single Family
3,201 - 5,700 1.53 per dwelling unit $132.33
Single Family
Very Large
> 5,700 Actual Impervious Area $0.0203 per square foot (1)
Multi Family
Apt., Condo, Townhome, Co-op
Flat Rate 0.33 per dwelling unit $28.54
Mobile Home Park or RV Park Flat Rate 0.33 per space $28.54
Non-Residential Actual Impervious Area Actual Impervious Area $0.0203 per square foot (2)
Agricultural (Exempt)    0
(1) Minimum assessment of $132.33 (1.53 ERU) per parcel
(2) Minimum assessment of $86.49 per parcel

2024 Proposed Stormwater Fee

Hillsborough County is considering an increase to the annual stormwater fee. Find out the details on the proposed fee and a list of frequently asked questions by clicking the button below:

2024 Proposed Stormwater Fee

Need assistance?

The Stormwater Management Program Hardship Exemption is an assistance program that helps eligible homeowners pay their annual Stormwater Utility Assessment (Stormwater Fee). Learn more.


Contact the Property Appraiser office if there are any discrepancies regarding the number of dwellings for which you are being charged.