The purpose of this rulemaking is to establish minimum flows pursuant to Section 373.042, F.S., for the Rainbow River System located in Marion County. The effect of the rule is to support the District’s water supply planning, water use permitting, ...

 

WATER MANAGEMENT DISTRICTS

Southwest Florida Water Management District

RULE NO.:RULE TITLE:

40D-8.041Minimum Flows

PURPOSE AND EFFECT: The purpose of this rulemaking is to establish minimum flows pursuant to Section 373.042, F.S., for the Rainbow River System located in Marion County. The effect of the rule is to support the District’s water supply planning, water use permitting, and environmental resource permitting programs.

SUMMARY: Section 373.042, F.S., requires the District to establish minimum flows and levels for water bodies located within the District’s boundaries. This rulemaking is necessary to establish a regular rule setting minimum flows for the Rainbow River System and associated springs in southwestern Marion County. Currently, an emergency rule to this effect exists. The establishment and periodic evaluation of minimum flows is required by statute to ensure that the minimum hydrologic requirements of the water resources and ecology of this spring group are maintained. The establishment of minimum flows for the Rainbow River System are being developed using previously peer-reviewed, Governing Board adopted methods.

SUMMARY OF STATEMENT OF ESTIMATED REGULATORY COSTS AND LEGISLATIVE RATIFICATION:

The Agency has determined that this will not have an adverse impact on small business or likely increase directly or indirectly regulatory costs in excess of $200,000 in the aggregate within one year after the implementation of the rule. A SERC has not been prepared by the Agency.

The Agency has determined that the proposed rule is not expected to require legislative ratification based on the statement of estimated regulatory costs or if no SERC is required, the information expressly relied upon and described herein: The District conducted an economic review of the revisions to the rule and determined that the impact or regulatory cost, if any, of the revisions will not exceed any one of the economic analysis criteria in a SERC as set forth in Section 120.541(2)(a), F.S. The revised minimum levels for this spring run is unlikely to constitute an additional significant regulatory constraint on groundwater or surface water withdrawals in the area due to existing resource conditions and regulatory constraints in the basin.

Any person who wishes to provide information regarding a statement of estimated regulatory costs, or provide a proposal for a lower cost regulatory alternative must do so in writing within 21 days of this notice.

RULEMAKING AUTHORITY: 373.044, 373.113, 373.171, FS

LAW IMPLEMENTED: 373.036, 373.042, 373.0421, 373.086, 373.709, FS.

IF REQUESTED WITHIN 21 DAYS OF THE DATE OF THIS NOTICE, A HEARING WILL BE SCHEDULED AND ANNOUNCED IN THE FAR.

THE PERSON TO BE CONTACTED REGARDING THE PROPOSED RULE IS: Doug Leeper, MFL Program Lead, 2379 Broad Street, Brooksville, FL 34604, [e-mail], (352)96-7211 or 1(800)423-1476 (FL Only) ext. 4272

 

THE FULL TEXT OF THE PROPOSED RULE IS:

 

40D-8.041 Minimum Flows.

(1) through (21) No change.

(22) Minimum Flow for the Rainbow River System.

(a) For purposes of this rule, the Rainbow River System includes the watercourse from the Rainbow Springs Group headsprings to the Withlacoochee River, including contributing tributaries, and all named and unnamed springs that discharge to the river.

(b) The Minimum Flow for the Rainbow River System is 95% of the natural flow as measured at the United States Geological Survey Rainbow River at Dunnellon, FL Gage No. 02313100. Natural flow is defined for the purpose of this rule as the flow that would exist in the absence of water withdrawal impacts. The Minimum Flow is based on a 5% reduction from the natural flow of 683 cubic feet per second, which was adjusted for groundwater withdrawals using hydrologic modeling for the period of record from 1965­–2015 at the United States Geological Survey Rainbow River at Dunnellon, FL Gage No. 02313100.

(c) Status assessments of the Minimum Flow for the Rainbow River System will be completed to determine whether the flow is below or projected to fall below the Minimum Flow. Each status assessment is independent from and not a determination of water use permit compliance or environmental resource permit compliance. Permit compliance is a regulatory function that is not within the scope of this subsection. As part of each status assessment, the District will use the following approach:

1. The District will evaluate the Minimum Flow annually to determine the extent to which the flow of the Rainbow River System has been reduced due to withdrawals as of the date of each status assessment at the United States Geological Survey Rainbow River at Dunnellon, FL Gage No. 02313100. The annual evaluation will be completed through a review of:

(a) flow data;

(b) water withdrawals;

(c) aquifer water levels;

(d) rainfall data; and

(e) hydrologic modeling.

2. The District will also evaluate the Minimum Flow every five years as part of the regional water supply planning process. This evaluation will include the use of hydrologic modeling.

3. If the Minimum Flow is being met based on the annual evaluation or the evaluation performed as a part of the regional water supply planning process, then no further actions are required beyond continued monitoring.

4. If the annual evaluation indicates the flow is below the Minimum Flow, or if the flow is projected to fall below the Minimum Flow within 20 years based on the evaluation performed as a part of the regional water supply planning process, the District will conduct a causation analysis to evaluate the potential causes of impacts on the Rainbow River System. 

5. Based on the causation analysis, the District will re-evaluate the Minimum Flow for the Rainbow River System, or adopt a recovery or prevention strategy consistent with the provisions of Section 373.0421(2), F.S.

(d) The District will re-evaluate the Minimum Flow by December 2027.

Rulemaking Authority 373.044, 373.113, 373.171 FS. Law Implemented 373.036, 373.042, 373.0421 FS. History–New 10-5-74, Amended 12-31-74, Formerly 16J-0.15, 40D-1.601, Amended 10-1-84, 8-7-00, 2-6-06, 4-6-06, 1-1-07, 11-25-07, 2-18-08, 3-2-08, 5-12-08, 5-10-09, 3-23-10, 3-28-10, 7-12-10, 8-2-10 (8), 8-2-10 (15), 10-16-12, 3-20-13(16), 3-20-13(17), 6-20-16, 3-15-18, 6-19-18, __.

 

NAME OF PERSON ORIGINATING PROPOSED RULE: Southwest Florida Water Management District

NAME OF AGENCY HEAD WHO APPROVED THE PROPOSED RULE: Southwest Florida Water Management District Governing Board

DATE PROPOSED RULE APPROVED BY AGENCY HEAD: March 26, 2019

DATE NOTICE OF PROPOSED RULE DEVELOPMENT PUBLISHED IN FAR: March 11, 2019