Colorado Basin Surface Water Supply Index with Historical Comparisons

SWSI values for Colorado's major river basins compare current water volume to historical records for the same month. The dataset includes monthly reports with year-over-year and month-over-month changes for each basin. Data is provided by the Colorado Division of Water Resources via data.colorado.gov, with reports updated as of March 2026.

Use Cases

• Forecast drought severity by analyzing trends in the SWSI column across the Report Month and Report Year time series.
• Assess basin-specific water stress by comparing the Change from Previous Year and Change from Previous Month columns across different Basin entries.
• Model reservoir operations by correlating SWSI values, which incorporate reservoir storage, with the NEP (Normal Exceedance Probability) metric.
• Benchmark current water supply against historical conditions using the SWSI Previous Year and SWSI Previous Month columns for anomaly detection.

Strengths

• Provides a standardized drought index (SWSI) calculated for multiple river basins.
• Includes comparative metrics like Change from Previous Year and Change from Previous Month for trend analysis.
• Data is updated regularly, with a last updated date in March 2026.

Limitations

• The total number of rows and historical depth of the time series are unknown.
• Geographic coverage is limited to the state of Colorado's basins.
• Sample data is unavailable to verify data distributions or potential null values.

Provenance

Source

Colorado Division of Water Resources (DWR), published via data.colorado.gov.

Collection Method

Calculated by comparing total water volume (streamflow, forecasts, reservoir storage) in a basin to historical volumes for the same month.

Time Range

null

Freshness

Updated as of March 2026; specific update frequency is not stated.

Geography

River basins and sub-basins within the state of Colorado, USA.