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Heat Source is a 1D model used to simulate stream thermodynamics and hydrology. Simulation of water temperature and flow dynamics over various scales (i.e. reach, watershed to basin scales) is made possible with high resolution spatially continuous data, coupled with deterministic modeling of hydrologic and landscape processes. Modules (executables) include simulation of effective shade, comprehensive heat and mass transfer and water temperature.

Geographic Location

Developed in Oregon. Used widely by ODEQ across Oregon. Some routines are used in Washington.


Surface water: continuous temperature data, USGS gage flow data, instantaneous temperature and flow data, channel morphological data, effective shade samples, stream corridor vegetation information, longitudinal thermal infrared data and meteorological data. Optional: LiDAR


Time series and longitudinal hydraulic, solar radiation, effective shade, temperature and energy flux profiles

Linkage to Other Models

Heat Source uses the output from Ttools.

Level of Effort

An intensive monitoring effort is required for the entire the model period. The model is simple to use, although requires understanding of basic modeling principles.

Basin Scale Opportunity Assesment