By Robert L. Knight
March 2016
The Suwannee River Water Management District is home to more than 300 artesian springs and aptly named the “springs heartland” of Florida. These springs discharge groundwater into the Suwannee, Santa Fe, Ichetucknee, and Withlacoochee Rivers.
Under pre-development conditions, these springs provided from 50 to nearly 100 percent of the average daily flows to these four interconnected rivers. Their combined flows, measured in billions of gallons per day, were the lifeblood of Florida’s Nature Coast, nourishing the Lower Suwannee River National Wildlife Refuge and supporting coastal fisheries.
Twenty four of these springs border the lower Suwannee River below its confluence with the Santa Fe River. The two largest springs in this reach, Fanning and Manatee springs, are in state parks established to protect them from development and over-exploitation. Four smaller springs along the Lower Suwannee River are located in county parks, and other springs are on land owned and managed by the Suwannee River district.
In response to long-term flow declines, the district in 2007 established minimum flows and levels (MFLs) for the lower Suwannee River and for Fanning and Manatee springs. These MFLs allow groundwater withdrawals to cause up to a 20 percent reduction in average spring and river flows.
In spite of these MFLs, flows in the lower Suwannee River continue to decline, and based on recent analysis, the MFLs for Fanning and Manatee springs are not being achieved. In fact, Fanning Springs has been down-listed from a first to a second magnitude spring. Spring flow reductions are being caused by excessive groundwater pumping for agricultural, industrial, and urban water uses.
In 2008 the Florida Department of Environmental Protection concluded that the Suwannee and Santa Fe rivers were impaired due to elevated nitrogen concentrations, resulting primarily from agricultural sources. In other words, these rivers and the springs feeding them were polluted and had been above the numeric nitrogen water quality standard for more than 20 years.
The department adopted a basin management action plan (BMAP) for the Santa Fe River in 2012. This nutrient reduction plan calls for a 50 percent cut in nitrogen loading to the Santa Fe River and springs. Unfortunately, the Santa Fe River BMAP does not provide a reasonable deadline for recovery or have the regulatory clout needed to actually effect the required water quality improvements.
Exploitation of North Florida’s abundant groundwater resources is weakening the heartbeat of the Suwannee River basin, including its tributaries and coastal estuaries. Groundwater that was once plentiful and clean is now depleted and polluted.
Groundwater depletion results in declining flows to North Florida’s spring-fed rivers. Current average flows in the Suwannee River are less than one half of historic flows, and more than 5,000 tons of nitrogen (a 90 percent increase) is now flowing out of the lower Suwannee River into the Gulf of Mexico every year. This excessive nitrogen load is resulting in a rising frequency of toxic red tide events at the mouth of the river, and in turn, killing off the live bottom that supports coastal fisheries.
Spring flows are truly the lifeblood of North Florida’s heartland. With a depleted and polluted aquifer, and with drying spring-fed rivers, the North Florida landscape is becoming more arid — an over-drained landscape, increasingly dominated by drought-tolerant plants and animals, and algae-infested springs.
The good news is that these human-caused impairments can be reversed. Spring flows can be restored to protective rates by reducing groundwater pumping from the Floridan Aquifer. Loading rates of nitrogen in the form of fertilizer and animal/human wastewater can be reduced in the springshed by implementing advanced best management practices for agriculture; advanced nitrogen removal for human wastewater disposal systems; and reducing the intensity of livestock feeding operations.
In response to the continued declining health of the springs along the Suwannee River, the Howard T. Odum Florida Springs Institute has prepared a comprehensive restoration strategy (www.floridaspringsinstitute.org/restoration-plans). This plan is different from previous efforts by the Department of Environmental Protection and water management district in that it outlines a holistic approach to restoration of the Suwannee’s springs and river resources by defining effective strategies to simultaneously restore both spring flows and water quality.
Existing laws are already in place to protect the springs heartland in perpetuity. What our springs need now are leaders with the vision and will to enforce those laws and achieve a sustainable future.