The Florida Department of Environmental Protection (FDEP), in collaboration with the Suwannee River and St. Johns River Water Management Districts, is proposing a new Minimum Flow and Levels (MFL) rule for the Santa Fe and Ichetucknee Rivers and associated Priority Springs. MFLs are the water flow and level thresholds below which significant harm to water resources or ecology is deemed to occur. This rule could affect all water users, including agricultural producers. While it’s expected to be finalized by the 2026 Florida legislative session, stakeholders should stay informed and submit public comments by September 30th, 2024.
This rule impacts water withdrawals in the North Florida Regional Water Supply Partnership area, covering counties such as Alachua, Baker, Bradford, Clay, Columbia, Duval, Flagler, Gilchrist, Hamilton, Nassau, Putnam, St. Johns, Suwannee, and Union.
The proposed rule aims to update the MFLs for the Lower Santa Fe and Ichetucknee Rivers and associated Priority Springs. The updated MFLs will serve as the basis for regulating water withdrawals in the consumptive use permit process. Key aspects of the proposed rule include:
Modification of Existing Permits:
- Existing consumptive use permits in the North Florida Regional Water Supply Partnership area will be modified to meet the new MFLs, potentially leading to changes or reductions in permitted water allocations.
- The modification process will incorporate new conditions into existing permits, including requirements related to offsetting impacts and water conservation.
Impact Evaluation: The proposed rule requires a thorough evaluation of the impact of all water withdrawals on MFL compliance points. These three MFL compliance points are river gages located at the Santa Fe River near Fort White, Santa Fe River at US HWY 441 near High Springs and Ichetucknee River at HWY 27 near Hildreth. The first gage near Fort White currently meets the required MFLs, while the gages near High Springs and Hildreth are in recovery, indicating their flow levels are below the required MFLs.
Permit holders are responsible for addressing their contributions to any identified impacts. This includes demonstrating that their water use will not worsen conditions at recovering MFL compliance points. If a permittee impacts multiple MFL compliance points that are in a state of recovery, their offset requirements will be determined based on the compliance point where their impact is greatest.
Calculating Offset: A permittee’s offset is calculated by determining their proportionate share for the recovering MFL compliance point. This is done by dividing the permittee’s individual impact (Ip) by the total impact at the MFL compliance point (It), using baseline average water uses from 2014-2018, and then multiplying by the 2014-2018 Net Flow Deficit (Infd).
For example, if a permittee’s water use reduces the flow at a recovering MFL compliance point by 0.05 cubic feet per second (cfs), and the total impact from all water uses (baseline 2014-2018) is 10 cfs, with a Net Flow Deficit of 6.3 cfs, the permittee’s required offset would be calculated as follows:
Proportionate Share = (Individual Impact (Ip) / Total Impact (It)) × Net Flow Deficit of the recovering MFL compliance point (Infd).
Calculation: (0.05 cfs / 10 cfs) × 6.3 cfs = 0.0315 cfs.
This means the permittee must offset 0.0315 cfs to help recover the MFL compliance point.
Note: In this example, based on a 0.0315 cfs impact, a farm with a baseline water use of 12 acre-inches per acre annually for a 135-acre pivot (averaged from 2014 to 2018) would need to reduce its usage by approximately 2 acre-inches per acre per year. This reduction would leave the farm with 10 acre-inches per acre for future annual use.
Offsetting Impacts: Water users may be required to implement offset projects to mitigate any adverse effects their withdrawals have on recovering MFL compliance points.
- Permittees can implement various types of projects to offset impacts, including water resource or supply development projects, retirement of water use, or other means that increase flow to MFL compliance points. These projects are designed to counterbalance the effects of water withdrawals. These could be individual or regional offset projects. One example of a regional offset project is the Black Creek Water Resource Development Project managed by St. Johns River Water Management District.
- Offset Credits: Water users who successfully implement offset projects may receive offset credits. These credits are applied to their permits, allowing continued water use while ensuring that the overall impact on the recovering MFL compliance points is neutral or positive. However, if an offset project fails to deliver the anticipated benefits, the permit holder may need to provide an equivalent replacement offset or face a reduction in their water use.
- This offset must be implemented as soon as practicable, but no later than 20 years from the rule’s effective date. If you increase your water use beyond what was recorded during the base condition period, you will also need to offset the new impact.
Water Conservation Requirements:
Irrigation System Maintenance and Evaluation: Agricultural permittees must maintain their irrigation systems to meet specific minimum distribution uniformity (DU) standards, which vary by system type. Distribution uniformity measures how evenly water is applied across an irrigated area to ensure efficient water use. Micro-drip systems should achieve a DU of 80–90%, micro-spray systems 75–85%, low-pressure center pivot or lateral move systems 75–85%, standard center pivot systems with end guns 65–75%, and in-place overhead sprinklers 70–75%. Mobile Irrigation Labs typically estimate DU during free evaluations for growers. To ensure compliance with these standards, permittees must submit evaluations of their systems, and there is interest in establishing an additional mobile irrigation lab in the Suwannee Valley if needed to help agricultural producers comply.
Transition to More Efficient Systems: For irrigation methods like seepage irrigation, permittees must submit a plan to transition to more efficient systems within the duration of the permit. This transition plan should outline how and when the improvements will be made, ensuring that water use is minimized and efficiency is maximized.
Water Conservation Measures: The rule introduces a tiered system for water conservation practices, each offering varying levels of water-saving potential. Agricultural permittees must demonstrate that they are implementing high-level water conservation measures or propose alternative methods with similar effectiveness. Key practices include using advanced irrigation technologies like soil moisture sensors and automated systems, converting to more efficient irrigation methods, and implementing strategies like conservation tillage and tailwater recovery (which capture and reuse runoff water from irrigation), along with Alternative Water Supply projects, which are prioritized due to their potential for water savings.
Public Comment: The rule is still in the development phase, and there will be opportunities to provide input. A public comment period is open until September 30th, 2024.
You can submit comments via email to: OWP_rulemaking@floridadep.gov
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