Coronet No. 4

ALAFIA RIVER (ENGLISH CREEK)· Hillsborough, Florida· Built 1930· Earth· 9 ft tall
Significant Hazard Tailings Private

Key Takeaway

Coronet No. 4 is classified as significant hazard in Florida. It was completed in 1930 and is 96 years old. Its primary use is tailings. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 9 ft (taller than 10.3% in FL)
Dam Length8,000 ft
Dam TypeEarth
Max Storage1.1K acre-ft
Normal Storage900 acre-ft
Surface Area131 acres
Drainage Area1 sq mi
Max Discharge20 cfs
Year Completed1930 (96 years old)
Year Modified1950
NID IDFL12002

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: July 24, 2003
State Regulated: Yes
Regulatory Agency: FDEP

Ownership

THE MOSAIC COMPANY

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Coronet No. 4?

Coronet No. 4 is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Coronet No. 4?

Coronet No. 4 is owned by THE MOSAIC COMPANY (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Coronet No. 4 built?

Coronet No. 4 was completed in 1930, making it 96 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Coronet No. 4?

Coronet No. 4 serves the following purposes: Tailings. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Coronet No. 4?

Coronet No. 4 has a dam height of 9 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was Coronet No. 4 last inspected?

Coronet No. 4 was last inspected on July 24, 2003. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.