In this section
Clay-Putnam prevention/recovery strategy development process
Review the multi-year
list of water bodies targeted by the District for development of MFLs.
Blue Spring, Volusia County
Minimum flow regime
A portion of the pool at Blue Spring in western Volusia County, Florida.
- Approved action plan
- Approved memorandum of agreement
- Minimum flows and levels program
- History of Blue Spring minimum flow regime development
- Overview of the rulemaking process
- Background documents
- Analysis of Blue Spring discharge data
- Human use and ecological evaluation of the recommended minimum flow regime for Blue Spring
- Springs of the District ▸ Blue Spring page
- Questions and answers
Manatees seek refuge in the warmer waters of Blue Spring Run.
Blue Spring State Park is located in Volusia County, Fla., two miles west of Orange City and adjacent to the St. Johns River. The park encompasses 2,483 acres of land with a variety of ecological habitats, including Blue Spring and Blue Spring Run. The spring and run have an estimated area of four acres and a length of 2,336 feet from the upper edge of the spring boil pool to the point of confluence with the St. Johns River.
Blue Spring is a first magnitude spring, meaning that it has a long-term average flow of at least 100 cubic feet per second (cfs) or 65 million gallons per day (mgd). Blue Spring and Blue Spring Run are classified as Class III waters by the state of Florida, meaning their designated use is for public recreation and the propagation and maintenance of healthy populations of fish and wildlife. The spring and run are also designated as “Outstanding Florida Waters” because they are located within a state park.
Water quality in the spring and run is characteristic of its source, the Floridan aquifer, exhibiting high water clarity, high dissolved solids, little or no oxygen, and stable temperature. The spring water remains at a nearly constant temperature of 73° Fahrenheit (°F) or 23° Celsius (°C).
Blue Spring is internationally famous as a winter, warmwater refuge for the endangered West Indian manatee (Trichechus manatus latirostris). The manatee is a tropical to subtropical species adapted to warm water that, in Florida, is at the northern edge of its geographical range. Due to their low metabolism, manatees have difficulty withstanding cold conditions and, therefore, they need to find a warmwater refuge during cold weather. Blue Spring is the only large naturally occurring manatee warmwater refuge on Florida’s east coast for the St. Johns River manatee population. The United States Fish and Wildlife Service (USFWS) has designated the spring and run as critical manatee habitat.
Manatees seek refuge in the warmer waters of Blue Spring Run when the temperature of the river drops below 68°F (20°C). Manatees typically begin congregating in the spring run in November and leave in March. The period between November 1 and March 31 is referred to as the “manatee season.” Manatee use of Blue Spring Run as a winter, warmwater refuge has increased dramatically since 1978, when routine manatee counts began. Based on counts performed for daily surveys, the maximum number of manatees observed on a single day has increased nearly seven-fold, from 28 in 1978 to 182 during the 2005 manatee season.
During the manatee season, manatees congregate in the spring run immediately upstream of the point where the cold, dark St. Johns River water meets the warmer, clear spring water. Where the spring water mixes with the St. Johns River, water clarity drops due to the relatively high dissolved color (tannic acid) in the river. This interface is referred to as the dark water intrusion, and is easily seen by the casual observer.
The St. Johns River Water Management District (District), pursuant to its statutory responsibilities, has approved a minimum flow regime for Blue Spring and Blue Spring Run. To develop the regime, the District formed the Blue Spring Minimum Flow Interagency Working Group (MFIWG). This group, which consists of experts from various participating organizations, including the Florida Department of Environmental Protection (DEP) and the Florida Fish and Wildlife Conservation Commission (FWC), assisted the District in the formulation of the minimum flow regime. The USFWS and Save the Manatee Club, Inc., also participated in the MFIWG, primarily in reviewing and commenting on draft recommendations.
The research efforts that support the minimum flow regime are based on an analysis of the vast daily database of manatee occurrence at Blue Spring State Park, as well as spring flow records, and river stage and river temperature data, collected and compiled by the U.S. Geological Survey and the District.
A portion of Blue Spring Run
The District’s Minimum Flows and Levels (MFLs) Program, mandated by state law (Section 373.042, Florida Statutes, (F.S.)), establishes MFLs for lakes, streams and rivers, wetlands, and groundwater aquifers. The minimum flows for surface water courses define the limit at which further water withdrawals would be significantly harmful to the water resources or ecology of the area.
MFLs are determined using the best available information and must also consider non-consumptive uses of water, such as fish and wildlife habitat, recreation, and water quality. Rule 62-40.310(4)(a), Florida Administrative Code (F.A.C.), directs the establishment of MFLs that seek to protect water resources, considering the environmental values associated with marine, estuarine, freshwater, and wetlands ecology.
Generally, MFLs designate a minimum range of water levels and/or flows (hydrologic conditions) that prevent significant harm to the water resources and above which water is available for reasonable-beneficial use. MFLs take into account the ability of most wetlands and aquatic communities to remain healthy with some change in water levels and/or flows. Therefore, MFLs may allow for some change to occur relative to the existing water levels and/or flows.
MFL determinations may be based on a wide variety of existing information, including biological, soils and topographical information collected at the study site; wetland and soils maps; aerial photography; scientific literature; water levels and/or flow data; and output from computer simulation models.
Water bodies for which the District has adopted MFLs include
Surface water courses
- Wekiva River at SR 46 bridge
- Black Water Creek at SR 44 bridge
- St. Johns River, 1.5 miles downstream of Lake Washington Weir
- Taylor Creek, 1.7 miles downstream of structure S-164
- St. Johns River at SR 44 near DeLand, Volusia County
- 100 lakes
- Seven wetlands
- Eight springs in the Wekiva River Basin (minimum spring flow and a level in the aquifer at each springhead)
The MFLs for these water bodies are contained in Chapter 40C-8, F.A.C.
Blue Spring Run where it discharges into the St. Johns River
- Initiated Blue Spring minimum flow regime studies
- Developed recommended minimum average annual flow of 134 cfs and supporting documentation
- Conducted independent scientific peer review, data analyses, and interagency discussions
- Formed the Blue Spring “Minimum Flow Interagency Working Group” (MFIWG) composed of staff from USFWS, FWC, DEP, Save the Manatee Club, Inc., and the District
- Held MFIWG meetings to direct and review studies
- Developed recommendations for the Blue Spring minimum flow regime
- Conducted and completed additional interagency discussions, analyses, and independent scientific peer review
- Completed reports to document process, incorporate additional analyses and peer review comments
- Held Public Workshops (March 23, 2004, April 20, 2004, and December 6, 2005)
- Published Notice of Proposed Rule (May 19, 2006)
- Opened Public Hearing (August 8, 2006)
- Published a Notice of Continuation of Public Hearing (September 15, 2006)
- Approved proposed rule as amended (October 10, 2006)
- Rule effective date is December 3, 2006
MFLs are adopted by rule. Chapter 120, F.S., governs the District’s rulemaking process. Generally, this process includes publishing, in the Florida Administrative Weekly (F.A.W.), a Notice of Proposed Rule Development, Notice of Workshops, and a Notice of Proposed Rule. After publishing the Notice of Proposed Rule, a rule adoption hearing is held before the District’s Governing Board, and the rule is then filed for adoption with the Department of State.
With regard to the Blue Spring Minimum Flow rulemaking effort, the District published a Notice of Proposed Rule Development on November 21, 2003, and again on November 23, 2005. The District held public workshops in Deltona, Fla. on March 23, 2004, April 20, 2004, and December 6, 2005. The workshops were held to inform the public about the rule development, answer questions, and receive public comments. In response to comments received at the workshops and in writing, along with comments from DEP, USFWS, FWC, and Save the Manatee Club, Inc., the District revised the draft rule. District staff obtained authorization from the District’s Governing Board to publish a Notice of Proposed Rule at the District’s May 9, 2006, Governing Board meeting. The Notice of Proposed Rule was published on May 19, 2006.
The Governing Board held a rule adoption hearing on August 8, 2006, and continued the Public Hearing until October 10, 2006. At the October 10, 2006, Governing Board meeting, District staff proposed an amendment to the proposed rule that reflects the incorporation of the most recent manatee season data into the rule. The Governing Board, by a vote of seven to one, approved the proposed rule as amended. A notice of change reflecting the amendment to the proposed rule was published on October 20, 2006. The rule effective date is December 3, 2006.