Current Conditions

The Great Salt Lake’s water level is influenced by precipitation, temperature, evaporation and runoff. It is a terminal basin, meaning it has no outlet, and once water arrives in the lake, it stays until it evaporates. So less water reaching the lake will, over time, ensure a smaller lake. Drought and warmer temperatures may also speed up the lake’s decline.

Runoff from the Uinta, Wasatch and Bear River ranges provides the primary water source for the lake. This runoff feeds the lake’s largest tributaries: the Bear River, the Jordan River and the Weber River. Combined, these sources supply nearly 70% of the lake’s water. The majority of the remaining water comes from direct precipitation on the lake, groundwater and intermittent streams in the West Desert.

The tools below present data that reflect current conditions impacting the lake.

Great Salt Lake Shoreline historical fluctuation

Great Salt Lake Levels

Graph showing Great Salt Lake Elevations
Screenshot of USGS Hydromapper tool zoomed into Great Salt Lake and Utah Lake.

USGS Hydromapper

Interactive site with real-time lake levels, salinity and groundwater data.

Screenshot: USGS National Water Dashboard Mapping tool zoomed in on Great Salt Lake.

USGS Streamflow

Daily streamflow conditions show how much water is flowing and how fast and high.

Reservoir Levels

Snow Water Equivalent (SWE)

SWE data reflects the amount of water in the snow if it melted.

Soil Moisture

Soil moisture impacts runoff efficiency. Dry soils soak up water before it refills reservoirs and lakes.

Great Salt Lake Salinity Converter

This tool converts between concentration, percent salinity, and density. It uses the number of grams of salt in a liter (almost a quart) or the weight of salt compared to the weight of water and salt (salinity percent by weight), or how heavy the salt and water are (density) and can convert to the other data types.

Brine Temperature

Brine Mass Concentration (Salinity)
Brine Mass Percentage (% Salinity)
Brine Density


* Cannot be used to derive concentration from a refractometer percentage.