N-4 Rockland Mine

UNNAMED CREEK· Polk, Florida· Earth· 40 ft tall
Significant Hazard Tailings Private

Key Takeaway

N-4 Rockland Mine is classified as significant hazard in Florida. Its primary use is tailings. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 40 ft (taller than 79.9% in FL)
Dam Length0 ft
Dam TypeEarth
Max Storage17.0K acre-ft
Normal Storage15.4K acre-ft
Surface Area440 acres
Drainage Area0 sq mi
Max Discharge0 cfs
NID IDFL00622

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: No
State Regulated: Yes
Regulatory Agency: FDEP

Ownership

THE MOSAIC COMPANY

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of N-4 Rockland Mine?

N-4 Rockland Mine 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 N-4 Rockland Mine?

N-4 Rockland Mine is owned by THE MOSAIC COMPANY (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

What is the primary purpose of N-4 Rockland Mine?

N-4 Rockland Mine 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 N-4 Rockland Mine?

N-4 Rockland Mine has a dam height of 40 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.

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.