Vista Inflow Forecast Ready to go Operational at Southern California Edison

Inflow Vista has been implemented for long-term and short-term forecasting of inflow to the Big Creek hydroelectric facilities, located on the San Joaquin River, in the Sierra Nevada mountains of central California.

The Big Creek development was America's first large scale integrated hydroelectric project. Construction began in 1911 on what is referred to as the South Fork of the San Joaquin. The total drainage area above the Big Creek 4 hydro plant is about 1200 mi².

The topography of the basin covers a wide range of elevations, from 1,200 to over 13,000 feet above mean sea level, with over fifty percent of the area above 7500 feet. The area receives much more precipitation than most other parts of California -- annual precipitation in excess of 50 inches per year is typical of the west slope of the Sierra Nevada. Most of the annual precipitation falls in the form of snow. Snow remains on the ground for an appreciable length of time each winter above elevation of 4000 feet.

The Vista set-up included twelve sub-watersheds, and due to elevation range, several watersheds were sub-divided into 2 layers to better capture the snow accumulation and melt processes. A database with 20 years of climatic and hydrometric data was compiled and used to calibrate the model. Calibration and verification results demonstrated that the model is capable of capturing the runoff dynamics, as seen here.