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Updated: Jul 5, 2026
12:44
Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
Using heat to characterize streambed water flux variability in four stream reaches
Hedeff I Essaid1, Celia M Zamora, Kathleen A McCarthy
1U.S. Geological Survey, 345 Middlefield Rd., Menlo Park, CA 94025, USA. hiessaid@usgs.gov
Journal of Environmental Quality
|May 6, 2008
Summary
Streambed water flux, crucial for understanding stream chemistry, was studied using heat as a tracer in agricultural watersheds. Humid regions showed significantly higher water flow through streambeds compared to arid regions.
Area of Science:
- Environmental Science
- Hydrology
- Geophysics
Background:
- Streambed water flux is essential for interpreting stream chemistry and subsurface reactions.
- Understanding temporal and spatial variability of streambed flux is critical for watershed management.
Purpose of the Study:
- To estimate streambed water flux using heat as a tracer.
- To compare heat tracer estimates with synoptic methods.
- To investigate the influence of physical heterogeneity and water level variability on flux.
Main Methods:
- Continuous temperature and head monitoring in four agricultural watersheds.
- Utilizing heat as a tracer to study water flux variability.
- Modeling one-dimensional vertical flow and heat transport with VS2DH.
- Comparison with synoptic methods like seepage meters and differential discharge measurements.
Main Results:
- Water flux was influenced by stream channel heterogeneity and temporal water level changes.
- Upward flux through streambeds was dominant for most of the study period.
- High-stage events caused flow reversals, leading to surface water infiltration.
- Humid basins exhibited an order of magnitude greater streambed water flow than arid basins.
- Seasonal flux variability and downward flux post-high streamflow were most pronounced in humid regions.
Conclusions:
- Heat tracing provides a viable method for estimating streambed water flux.
- Streambed flux is highly variable in time and space, influenced by watershed characteristics.
- Humid regions experience greater streambed water exchange than arid regions, with significant seasonal patterns.
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