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Updated: Jun 22, 2026
09:49
Visualizing Hyporheic Flow Through Bedforms Using Dye Experiments and Simulation
Published on: November 18, 2015
Exchange flow in a shallow lake embayment.
Sveinn O Pálmarsson1, S Geoffrey Schladow
1Department of Civil and Environmental Engineering, University of California, Davis, California 95616, USA.
Summary
Convectively driven currents in lakes transport materials and contaminants like mercury away from the shore. These flows help reduce particle accumulation in shallow littoral zones, moving them offshore for potential burial or further transport.
Area of Science:
- Environmental Science
- Limnology
- Fluid Dynamics
Background:
- Littoral zones of lakes are susceptible to convectively driven currents.
- These currents are caused by differential heating or cooling of shallow waters.
- Such flows can result in surface or bottom return flows.
Purpose of the Study:
- To investigate the presence and characteristics of convectively driven currents in a lake's littoral zone.
- To determine the magnitude and transport potential of these flows.
- To assess the impact of these currents on particle and contaminant distribution.
Main Methods:
- Field measurements were conducted in a shallow embayment of Clear Lake, California.
- Observations covered a variety of summer conditions.
- Flow patterns and transport phenomena were analyzed.
Main Results:
- Both types of convectively driven flows (surface and bottom return) were observed.
- These flows have sufficient magnitude to transport materials up to 0.5 km.
- Evidence of advection and dispersion processes was noted.
Conclusions:
- Convectively driven currents play a significant role in sediment and contaminant transport in lake littoral zones.
- These flows can mitigate the accumulation of particles and associated contaminants, such as mercury.
- Offshore transport facilitates permanent burial or further movement of materials.
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