Final Biennial Assessment 2022-2024 Study List and Study List Removals

Final Biennial Assessment 2022-2024 Study List and Study List Removals

(August 19, 2024)

The Watershed Assessment Section announces the Biennial Assessment 2022-2024 final assessment lists of waterbodies and water segments proposed for addition to the Study List and Study List Removals. The FINAL assessment lists were developed pursuant to Chapter 62-303, Florida Administrative Code, and include all 29 basins in the state. In addition to the final assessment lists in spreadsheet format, an interactive map titled "Biennial Assessment 2022-2024 Final Lists" is available that shows the geographic location of the waterbodies and waterbody segments by WBID that are proposed for addition to the Verified List, Delist List, Study List, or Study List Removals. These assessment lists were produced with water quality and biological data included in the IWR Run 64 Database that has been received by the department as of July 13, 2022. They also incorporate station-WBID assignment updates, WBID classification updates and/or data exclusions based on a preliminary evaluation by department staff.  

For best results, print on legal size paper (8.5 x 14).

2022-2024 Final Study List and Study List Removals

A Class I, II, III, or Class III-Limited water shall be placed on the Study List in assessment category 4d if:

• A waterbody with a statistically-significant (at the 95 percent confidence level) increasing temporal trend in annual geometric means for TN, TP, nitrate-nitrite, or chlorophyll a and there is a reasonable expectation that the water will become impaired within 10 years.
• A waterbody that does not achieve the Biological Health Assessment provisions in Rule 62-303.430, F.A.C., but a cause has not been identified.
• A waterbody verified as not meeting the dissolved oxygen criterion pursuant to the verified list requirements, but a cause has not been identified.
• For streams meeting the definition in subsection 62-302.200(36), F.A.C., that do not have a site specific numeric interpretation of the narrative nutrient criterion, the nutrient thresholds in subparagraph 62-302.531(2)(c)2., F.A.C., are exceeded based on data from the last 7.5 years and insufficient Biological Health Assessment, chlorophyll a, or other response variable data are available to fully assess achievement of the nutrient provisions in paragraph 62-302.531(2)(c), F.A.C.
• There are fewer than twenty samples for a bacteriological water quality criterion, but there are five or more samples that do not meet an applicable water quality criterion based on data from at least five temporally independent sampling events;
• A waterbody segment is verified as not meeting the bacteriological water quality criterion pursuant to Part IV of this Chapter, but the department determines that additional study is needed to evaluate whether the exceedances are due to natural sources given the predominance of natural land uses in the watershed or based on information submitted to the department; or
• A waterbody exceeds a generally applicable criteria, but the department receives a SSAC petition pursuant to Rule 62-302.800, F.A.C., and additional time is needed to review and process the petition.

A Class I, II, III, or Class III-Limited water shall be placed on the Study List in assessment category 4e if:

• A waterbody where pollution control mechanisms are in place or planned that meet the requirements of subsections 62-303.600(1) and (3), F.A.C., except that there is uncertainty when water quality standards will be attained and the waterbody segment requires additional study;

Waterbodies placed into assessment category 4d will be targeted for strategic monitoring before the next cycle of assessments for that waterbody.  For waterbodies placed into assessment category 4e, the department shall evaluate progress towards attainment of water quality standards. Please note that the department will submit waterbodies included on the Study List to EPA Region IV as water quality limited segments for inclusion on Florida’s 303(d) list in accordance with the Clean Water Act. 

Waterbody-parameter combinations that no longer meet the listing requirements for the Study List, as identified in Rule 62-303.390, F.A.C. are submitted to EPA for removal from the 303(d) List. There are several reasons for requesting removal from the 303(d) List including, but not limited to, more recent or accurate data, flaws in the original analysis, site specific data or information to support natural conditions, and changes in water quality conditions.