District Deactivates Lower Hillsborough Flood Detention Area, Returns to Normal Operating Conditions

News Release

The Southwest Florida Water Management District (District) has deactivated the Lower Hillsborough Flood Detention Area (LHFDA), reopening the S-155 structure and allowing boat traffic to resume along that portion of the Hillsborough River. High water levels caused by Hurricane Irma have receded, allowing the Hillsborough River to return to its natural flow pattern.

In September, the Hillsborough River reached an elevation of 25 feet above sea level, which triggered the Army Corps of Engineers activation level of the Lower Hillsborough Flood Detention Area (LHFDA). This involved stopping the flow of the Hillsborough River, before it reached the City of Temple Terrace and City of Tampa, and redirected the water into the LHFDA, which was instrumental in preventing flooding from the Hillsborough River in Temple Terrace and the City of Tampa.

District staff redirected the flow of the river by closing the S-155 structure. The S-155 structure is located north of Morris Bridge Road and east of I-75 and can be seen from I-75 as you cross the Hillsborough River.

The Tampa Bypass Canal system was constructed in response to massive flooding caused by Hurricane Donna in 1960. The system is designed to divert flood waters from the Hillsborough River into the 16,000-acre LHFDA. As the detention area fills with water from the river and the surrounding 450-square-mile area, the flows then enter the Tampa Bypass Canal and are safely diverted to McKay Bay, bypassing the cities of Temple Terrace and Tampa.

The system is made up of five flood control structures located along the 15.7-mile canal. In addition to providing flood control, the Tampa Bypass Canal also serves as a water supply source to help meet the drinking water needs of the Tampa Bay area.