Water supply

The St. Johns River as a water supply source

In many areas of the St. Johns River Water Management District, groundwater supplies have reached their sustainable limit, or will reach these limits in the near future and the traditional water source — fresh groundwater from the Floridan aquifer — will not be able to meet all future needs.

Water conservation will continue to play a vitally important role in sustaining Florida’s water supply. Increasing water conservation may defer the need for more expensive and challenging alternative water supply solutions. While water conservation alone won’t solve all of our future water supply problems, it will have a direct bearing on the size, scope and timing of alternative water supply projects that will ultimately need to be developed.

Sunrise near Lake Jesup in Seminole County

Alternative sources may include seawater, brackish (slightly salty) groundwater, reclaimed water, and surface water from our rivers.

As mandated by the Florida Legislature and as part of its water supply planning program, the District must identify potential water sources and investigate if and to what extent alternative water supply sources can be developed and used without harming the environment. Legislation passed in 1997 required the state’s water management districts to complete specific water supply planning activities and initiate water resource development projects.

Proposals to permit the use of a limited quantity of water from the St. Johns River and/or the Ocklawaha River have generated significant public interest and discussion. The proposals call for diverting limited quantities of water from these rivers while maintaining minimum flows and levels (MFLs) that have been established by the District, or will be established in the near future. The purpose of the MFLs is to protect the water resources and ecology of the area. That is, natural systems needs as defined by minimum flows and levels are satisfied first before any water supply withdrawal is allowed. MFLs address the entire flow regime of the river (high flow, moderate flow and low flow) and any proposed water supply withdrawal must demonstrate compliance with all established MFLs before a consumptive use permit is issued. If required to ensure compliance with MFLs, specific projects can be designed to withdraw water during times of moderate to high flow so that no water is withdrawn during periods of low flow.

Scenes from the Middle St. Johns River Basin