We manage stormwater systems for the common good of the community by repairing and maintaining public stormwater facilities

Hillsborough County’s Stormwater Program provides for the maintenance, rehabilitation, and construction of the public stormwater movement 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.

What is Stormwater? - Video

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 fee 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 current assessment structure will utilize an “Equivalent Residential Unit”, or ERU, as the basis for most assessments. The average single-family residence in the County includes 4,267 square feet of impervious surface (roofed, paved, or similar surface), which equals one ERU.
  • The 2024 assessment for one ERU is $86.49

Program for help with paying the fee

Visit the Stormwater Management Program Hardship Exemption page to learn about the assistance program that helps eligible homeowners pay their annual stormwater fee on their tax bill.

Fee schedule

Assessments for specific parcels are based on either an assigned ERU or the actual impervious square footage, as shown in the chart below:

Calendar Years 2023 & 2024 (Resolution No. R-23-068)

Property Classification

Building Footprint (total gross area in square feet)

Assigned ERU

2024 Annual Stormwater Assessment

Single Family - Small

100 - 1,500

0.55 per dwelling unit


Single Family - Medium

1,501 - 3,200

1.00 per dwelling unit


Single Family - Large

3,201 - 5,700

1.53 per dwelling unit


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


Mobile Home Park or RV Park

Flat rate

0.33 per space



Actual impervious area

Actual impervious area

$0.0203 per square foot (2)

Agricultural (Exempt) 




(1) Minimum assessment of $132.33 per parcel
(2) Minimum assessment of $86.49 per parcel

Stormwater and stormwater fee FAQs

Stormwater & the Stormwater System
Stormwater Annual Assessment


Contact the Property Appraiser office if there are any discrepancies regarding the number of dwellings for which you are being charged. Questions regarding the assessment can be addressed with Hillsborough County at (813) 635-5400.

Last Modified: 4/30/2024, 4:51:07 PM

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