Withlacoochee River Flooding

Your Questions Answered

September 2018

Q:  Why is the Withlacoochee River experiencing flooding again this year?
Throughout the spring and summer, above average rainfall has saturated soils and filled wetlands and swamps that are no longer able to store additional rainfall.

Q:  Is river flooding a normal occurrence?
The Withlacoochee River naturally floods when it’s watershed is saturated and continues to receive high rainfall.

Q:  Can water be diverted to the Hillsborough River?
Flows from the Green Swamp primarily occur north to the Withlacoochee River. When water levels in the Green Swamp are high enough, flow also occurs south to the Hillsborough River. There are no structures or dams in the Green Swamp that control flow to either the Withlacoochee or Hillsborough rivers. Currently, the river is naturally draining to both the Withlacoochee and Hillsborough rivers.

Q:  Are there any structures or dams along the Withlacoochee River and what are their purpose?
The Wysong Structure is located between Citrus and Sumter County just downstream of Lake Panasoffkee. During times of low to normal flow, Wysong is used to conserve water upstream along the river and in Lake Panasoffkee. During high flows, such as now, Wysong is fully lowered and has no impact on the flow of the river. The Inglis Dam, located on Lake Rousseau, is used to divert excess flow to the Gulf of Mexico.

Q:  Can the Wysong Structure be opened to help lower water levels upstream?
The Wysong Structure has been completely lowered since early August and currently has no effect on water levels or flows along the Withlacoochee River.

Q:  How far upstream does the Inglis Dam affect river levels?
The Inglis Dam on Lake Rousseau has been opened since July, sending excess river flow to the Gulf of Mexico and helping to keep Dunnellon below flood stage. The Inglis Dam has no effect on river levels upstream from Dunnellon or in Lake Panasoffkee.

Mark Fulkerson, Ph.D., P.E.
Senior Professional Engineer
Southwest Florida Water Management District