Water Control Structures

Your Questions Answered

May 2020

The Southwest Florida Water Management District maintains and operates 86 water control structures throughout the District’s 16-county region. The Southwest Florida Water Management District’s Structure Operations Manager Mike Bartlett explains how these structures help provide flood protection, manage lake water levels and prevent salt water from flowing up freshwater streams and creeks.

Q: What is a water control structure?
A: The primary purpose of the Southwest Florida Water Management District’s (District) water control structures is to manage the flow of water. Water control structures vary greatly in size and are used for multiple purposes. The District’s water control structures can be classified into three main categories: flood control, salinity barriers and water conservation structures. These structures allow the District to provide flood control, water conservation and water supply protection, as well as preserve water quality and environmental assets.

Q: What is a flood control structure?
A: The District has 18 structures that are designated for flood control. Flood control structures are permanent structures that are specifically designed and used for reducing flood impact in local areas. Flood control structures and their corresponding canals are designed to handle large volumes of water for a sustained period of time. The District has guidelines which provide guidance when to operate the flood control structures.

Q: What is the largest flood control structure system in the District?
A: The largest flood control structure system in the District is the Lower Hillsborough Flood Detention Area (LHFDA) and Tampa Bypass Canal (TBC) used to divert floodwaters from the Hillsborough River around the cities of Tampa and Temple Terrace. Floodwaters diverted from the river are routed through the TBC and discharged into McKay Bay. The TBC also protects the City of Tampa’s Hillsborough River Dam and reservoir, which is the major source of drinking water for the City of Tampa and surrounding areas.

Q: How are the structures operated?
A: Water control structures can be operated remotely or manually. All the District’s mission-critical water control structures, including the 18 flood control structures, are operated remotely by staff using a computer. This allows staff to operate structures 24 hours a day, seven days a week from any location where there is internet access. Approximately half of the District’s water control structures must be manually operated, with staff having to be physically present at the location to operate the structure.

Q: What is a water conservation structure?
A: Most of the District’s structures are water conservation structures, used to conserve water or hold water in lakes during dry times. These structures are operated during rain events to assist in maintaining water levels. Their primary purpose is to protect and maintain natural systems. Water conservation structures are not designed for flood control and do not have the ability to move large volumes of water caused by intense rainfall events.

Q: What is a salinity barrier?
A:  The primary purpose of a salinity barrier is to prevent salt water from penetrating inland into freshwater channels and lakes. An example of this would be Structure 551 (S-551), a salinity barrier located on Lake Tarpon in Pinellas County. The structure keeps saltwater from intruding into Lake Tarpon from Tampa Bay. The S-551 structure is a dual-purpose structure as it is also designated a flood control structure.

Q:  With hurricane season right around the corner, how does the District prepare structures for possible severe weather?
A:  To prepare for hurricane season, staff conducts annual hurricane readiness checks of all the District’s structures to ensure they are working properly. This includes making sure all structure gates are functioning correctly and that each emergency generator is working and fully fueled.

Mike Bartlett
Structure Operations Manager
Southwest Florida Water Management District