Water Stewardship

Phosphate mining

Water is a key component in Mosaic's phosphate mining and fertilizer production processes, and we monitor our water use very carefully. All Mosaic groundwater use in Florida is pursuant to a permit issued by the Southwest Florida Water Management District (SWFWMD). We report our usage every month to SWFWMD, ensuring our usage remains below each facility's permitted limits. Any water that leaves our Florida facilities must be sampled to ensure compliance with stringent water quality standards.

Phosphate, as it occurs in nature, is incorporated into a matrix of clay and sand and must be separated to yield a usable fertilizer ingredient. In the mining process, water is used as a separation tool, beginning with washing the clay and sand from the phosphate rock. Water is also used to transport slurry to the beneficiation plants for further processing and to transport clay to storage areas and sand to reclamation sites. Mosaic manages this water to maximize recycling and keep the need for new water at a minimum.

Water Stewardship

Mosaic's Water Stewardship Program:

  • Uses recycled water for grinding rock in ball mills — saving 2,131,200 gallons of freshwater per day
  • Uses treated water instead of fresh water for plant wash downs — saving 604,800 gallons of freshwater per day
  • Improves seals on pumps — saving 218,900 gallons of freshwater per day
  • Recycles water previously treated as waste — saving 1,008,000 gallons of freshwater per day
  • Uses reverse osmosis units to feed demineralization systems — saving 162,400 gallons of freshwater per day
  • Reduces water used to transport matrix in the field — saving 5,040,000 gallons of freshwater per day

*All savings estimates are based on full production rates


As such, about 95% of the water used at our phosphate mines is recycled through our recirculation systems. These systems must also handle annual rainfall — that can vary from 30 to 70 inches per year — and safely and efficiently release excess rainfall back into the adjacent rivers and streams through National Pollutant Discharge Elimination System (NPDES) outfalls. The volume of water that leaves our mine sites on an annual basis tends to approximate the volume of water that would leave the area through runoff if our mines were not present.

Water quality monitoring and containment around our mine sites are important tools to ensure that water released is only through NPDES outfalls and that it meets stringent water quality standards. We recognize that several of the major creeks and rivers that flow through our property are significant sources of drinking water for downstream communities. These creeks and rivers also contribute to important ecosystems that are not only important for the role they play in the region's environmental health, but also contribute to the recreational and economic vitality of southwest Florida.

To ensure that our operations are not adversely impacting the quantity or quality of water in our areas of operation, Mosaic works with the Peace River Manasota Regional Water Supply Authority and its member governments in the Horse Creek Stewardship Program.

This program has been a valuable addition to our sustainability program. It encourages public review of our mining activities and promotes transparency. Mosaic plans to build on this important work — in the coming year we will launch the Peace River Stewardship Program. The Peace River is a critical part of life in southwest Florida.