Lake Jackson in north Tallahassee is experiencing a dry down event, during which part of the lake drains into a sinkhole. The sinkhole area, which was recently inundated with water from seasonal rains, is now exposed again as of July 11, 2021 during a secondary draining. The dry down is attracting many visitors who are curious to see this natural phenomenon. If you are planning to visit Lake Jackson, please take precautions and stay safe. DEP also has created an FAQ about the dry down.
Foot traffic is permitted, however, visitors to Faulk Landing and the sinkhole area should use caution. Smaller sinkholes (swallets) are unmarked and footing is unpredictable on the soft mud and vegetation throughout the lake bottom. Visitors should not go down into the sinkhole or remaining pools - the sediment may collapse along the sinkhole walls and the lake bottom sediments are unstable.
All fishing, hunting and boating regulations are still in effect, and are administered and enforced by the Florida Fish & Wildlife Conservation Commission (FWC). Fishing is allowed in the remaining water bodies of the lake and launching vessels is permitted at designated public boat landings, with the exception of Faulk Landing.
Lake-bottom driving with any motorized vehicle is prohibited and strictly enforced. All biological, cultural and historical resources are protected on sovereign submerged state lands. State and local managing government agencies will work together on research, monitoring, management and outreach as the dry down event progresses.
Porter Hole Sink, located approximately 650 feet (200 meters) north of Faulk Landing in Lake Jackson, drained its remaining water from June 4-7, 2021, refilled, and then drained again July 7-11, 2021. Lake levels have been trending downward since 2019 due in part to long-term regional drought conditions and lack of heavy, localized precipitation events within the lake’s basin that are needed to sustain lake levels. “Full pool” water level conditions are considered at approximately 86 feet above sea level (referenced to NAVD88). As of June 9, the lake level at the Miller Landing gauge read 78.8 feet NAVD88.
During Sunday, June 6, remaining pooled water disappeared into the roughly 28-foot deep hole through the limestone and clay lake bottom. Several streams and seepage from the sink’s slopes continued drain to the portion of the lake near Faulk Drive over the next few days, eventually isolating the sub-basin. Currently, five of the six dry down sub-basins within Lake Jackson are holding varying amounts of water, providing refuge for wildlife (i.e. US-27/Miller Landing, Church Cove, Crowder Landing, Meginnis Arm, and north of the Cattle Gap). Porter Hole Sink was drained for about two weeks (June 7-21), refilled again from June 24 - July 6, and is currently drained again and visible from Faulk Landing. Conditions change rapidly at the sinkhole with precipitation. Porter Hole drained most recently in 1999, 2006 and 2012. Lime Sink, the other major sinkhole, last drained in 2000, but does not appear to be active currently.
Lake Jackson is internationally known for its unique hydrology and trophy largemouth bass, and as an outstanding habitat for wading birds, waterfowl and a diversity of other wetland species.
Lake Jackson is located within the northern boundaries of the Tallahassee Hills physiographic region. This region covers a 25-mile-wide strip of upland formations spanning five counties in northwest Florida from the Withlacoochee River to the Apalachicola River. The topography surrounding the lake has an elevation of 200 to 230 feet above sea level, and thus, the steep hills form the sub-basins that give Lake Jackson its shape.
Lake Jackson is a shallow-water body that has an average depth of 6 feet except for two major sinkholes - Porter Hole Sink and Lime Sink - that have a localized depth of about 28 feet. The lake was formed through the dissolution of limestone over time causing the collapse of the overlaying sediment and forming the lake basin. Bottom leakage, sinkholes and swallets, long-term drought and a lack of recent, heavy rainfall events can create conditions that contribute to low lake levels and slow draining. In the last stages of a sinkhole draining, though, it can appear as if the lake dries within hours or days. Although the sinkholes are likely draining constantly, they can be partially or completely plugged with sediments and organic matter. The limestone, clay or organic matter plugs can collapse unpredictably when groundwater levels drop. As a result, lake water can funnel into the aquifer and dramatically lower the water level. The lake can also fill up just as quickly as it had disappeared after large rainfall events because the lake lies within a hydrologically closed basin (42 square miles) and is directly impacted by precipitation.
The lake is best explored by paddlecraft and boats or a spotting scope from one of the many landings. Outboard motorboats, mud motors and air boats are all used, depending on lake level. There are nine boat landings that provide access to the aquatic preserve. Kiosks at each access point provide information and maps.
Lake Jackson has served as an important natural resource to communities long before its designation as an aquatic preserve in 1973. The Fort Walton Culture of 1200 to 1500 A.D. thrived in the early environmental setting of the aquatic preserve and surrounding areas. The remains of their ritualistic culture can be found at Lake Jackson Archaeological Mounds State Park. The Southeastern Ceremonial Complex located in the park is evidence of an advanced community structure that existed around 1200 A.D. near Lake Jackson. The earthen mounds have been preserved to offer visitors the opportunity to look back through time into the area's rich cultural history.
Clastic upland lakes are generally characterized as shallow to relatively deep, irregular-shaped depressions or basins occurring in uplands. They have surface inflows but are often without significant outflows. Water is generally dissipated through evaporation and transpiration, but it may also disappear through sinks that connect with the aquifer, especially during prolonged droughts.
The karst topography of North Florida produces numerous sinkholes from the dissolution of the underlying limestone. Lake Jackson has small- to medium-size sinkholes scattered across the bottom. The lake's natural dry down and refill cycles are determined by the activity of these sinks and the amount of rainfall in the area. The sinkholes are important to the lake's ecosystem because natural periodic draining creates a cleansing effect for the lake, reducing invasive aquatic vegetation and exposing organic sediments that eventually decompose, revealing sand bottom habitat.
Wet prairies are communities of non-woody vegetation found on continuously wet but not inundated soils on flat gentle slopes. They are dominated by a mixture of grasses and sedges in the wetter portions. Wet prairies in North Florida are some of the most diverse communities in the U.S. with an average of more than 20 species per square meter. These communities are very sensitive to alterations to the soil surface that can alter the hydrology. Wet prairies are prevalent in the northern section of Lake Jackson near the "cattle gap."
The fluctuating water levels within the aquatic preserve prevent the domination of any one invasive species, but also creates enough disturbance for some infestations to thrive. The lake's main threats are from hydrilla, water hyacinth, Cuban bulrush, and Chinese tallowtree. Management is achieved by working closely with FWC’s Invasive Plant Management Section to mitigate their populations in both aquatic and riparian zones. Hydrilla is managed by herbicide treatment and sterile grass carp stocking. Natural dry down events also knock back hydrilla populations in shallow areas, but infestations usually remain in the lake's deeper sections. Waterfowl also use hydrilla as a food source in winter. Other aquatic exotics are treated with appropriate types and amounts of herbicide. Chinese tallowtree infests lake buffer - or riparian - areas and is resilient to varying water levels once established. Intensive management of this exotic tree was initiated in 2020-2021, targeting dense stands of mature trees with selective herbicide application. Long-term goals include replacing tallowtree areas with native tree canopy for increased nesting and foraging habitat for wading bird species.
The exotic island apple snail - originally from South America and a favorite food of the limpkin - is present in the lake and its population varies with lake levels. The snail’s impact on the native communities is currently unknown. Future monitoring and research projects are being considered to learn more about the snail’s population status in the aquatic preserve and potential management options.
Lake Jackson Aquatic Preserve staff coordinate all management and outreach with help from partners, including the City of Tallahassee, Leon County, FWC, Northwest Florida Water Management District, Friends of Lake Jackson, regional universities, lake landowners and volunteers. Aquatic preserve programming includes a seminar series and lake cleanups, attending local festivals and schools, landowner initiatives (such as the Adopt-A-Buffer Program, 2020) and land management guides, and providing lake-conservation information on kiosks, brochures and signage. The public can participate in a citizen science monitoring project by submitting photos at two Chronolog stations featured on the lake at Jackson View and Sunset landings. Time-lapse photos of lake level, vegetation, wildlife and recreation contributed by the public can be viewed at https://www.chronolog.io/project/Lake-Jackson-Aquatic-Preserve.
July 12, 2021 - 12:01pm
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The Florida Department of Environmental Protection is the state’s lead agency for environmental management and stewardship – protecting our air, water and land. The vision of the Florida Department of Environmental Protection is to create strong community partnerships, safeguard Florida’s natural resources and enhance its ecosystems.