History and Background

Description:  The BSF is the densely-packed salt remnants of an ancient lake bed formed over thousands of years.  Originally 96,000 acres in size, the unique geologic phenomenon in northwestern Utah has been reduced to about 30,000 acres.  The State of Utah nominated the BSF for inclusion on the National Register of Historic Places in 1973.  It was designated in 1975.   Besides sodium chloride (table salt), the BSF is composed of potassium, magnesium lithium and other minerals.  Water and wind shape the BSF throughout the year.  A shallow layer of standing water floods the surface during the cooler months (November-May).  The water slowly evaporates over the warmer spring and summer months while the wind acts to smooth the surface. 

Use:  Beyond its irreplaceable beauty, the BSF possesses rare physical qualities which make it a destination for land speed racing, filmmaking and sightseers.  The BSF has been used for racing since 1914 and countless land speed records have been set at the site.  For example, the 300, 400, 500, and 600 mile per hour land speed barriers were broken on its natural straightway.  The world-famous Speed Week dates back to 1949 and the BSF’s protected status recognize the importance of racing as a compatible use.

Management:  The BSF is managed by the U.S. Bureau of Land Management (BLM).  Beyond its placement on the National Historic Registry, the BLM issued the BSF Recreation Area Management Plan (Plan) in 1985 and established criteria for managing the lands as the “Bonneville Salt Flats Special Recreation Management Area” (SRMA) and as the “Area of Critical Environmental Concern” (ACEC).

Salt Laydown Project:  The BSF was once at least 5 feet thick near the center but it is now only inches thick. There is a demonstrated process to replenish the BSF salt crust.  In 1997, brine water was pumped onto the salt flats by the mining contractor at the rate of 1.5 million tons of salt each year for 5 years.  Over each winter, a high-quality brine (water and salt) was pumped to the north side of I-80 and discharged onto the southern portion of the BSF.  The salt flats are covered with water from rain and snow for much of the year.  The discharged brine dissolved and mixed in the transient pond and then spread across the salt basin.  The pond evaporates during the hot summer months, allowing the pumped salt to become part of the crust.  During the five-year program, the salt flats increased in thickness and hardness and the project significantly improved the aquifer which supports the salt crust volume.  A BLM commissioned study concluded that the laydown project “demonstrated that sodium chloride in brine removed from the BSF for mineral extraction can be replenished.  …The laydown project helped maintain the ion mass balance in the shallow-brine aquifer associated with the BSF by replacing 4.2 million tons of salt estimated to have been removed during the five-year project, while providing a net addition of 2 million tons of salt to the shallow brine aquifer.”  The salt laydown project is now ongoing.  Nearly 1.0 million tons of has salt were pumped onto the BSF during the 2011 and 2012 winter months.

Link to BLM Information: http://www.blm.gov/ut/st/en/fo/salt_lake/recreation/bonneville_salt_flats/Bonneville_Salt_Flats_History.html