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Wireless Sensor Network Monitoring of Post-Wildfire
          Debris Flow Initiation: Joel P. Johnson
Project Title: Wireless Sensor Network Monitoring of Post-Wildfire Debris Flow Initiation
Mendenhall Fellow: Joel P. Johnson, (650) 329-4919,
Duty Station: Menlo Park, CA
Start Date: November 13, 2007
Education: Ph.D. (Geomorphology), MIT, 2007
Research Advisors: Daniel Malmon, (650) 329-4934,

Project Description: A wireless sensor network (WSN) is being developed for environmental monitoring capable of resolving changes in active hillslope hydrology at high spatial and temporal resolutions.  Sensors that measure precipitation, soil moisture, overland flow and imagery will be integrated to monitor the hydrologic responses of hillslopes and first-order channels.  This work is being done in collaboration with computer scientists at the University of California Berkeley and Stanford University (Joe Hellerstein, Philip Levis, Kevin Klues, and David Chu).

The primary scientific question that will be explored with the hydrological WSN is this:  how do runoff and infiltration characteristics of the ground surface change with multiple precipitation events as fire related materials (wood ash cover, loose sediment, hydrophobic soils) are stripped off of the landscape?  It is precisely these hydrologic controls that dictate whether (1) debris flows will be triggered by bulking up from wood ash and surficial sediment, (2) discrete hillslopes will fail due to oversaturation (triggering landslides and possibly debris flows), or (3) flooding alone will occur.  The hydrological WSN will be used to monitor environmental conditions in the headwaters (hillslopes and first-order channel) of a recently burned small steep basin where debris flows are likely to be triggered.  The monitoring results will be combined with detailed surveys of landscape form and surface properties (for example, ash cover, sediment size) to understand the transport of water (subsurface and surface) and sediment.  This project will quantify aspects of how the risks of hydrological hazards change over several months following a wildfire. In addition, other applications of wireless sensor monitoring are being explored, including arroyo incision, interactions of vegetation, flow and infiltration, and embedding sensors into “smart rocks” that can be transported in natural and laboratory flows. 

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Last modified: 16:08:29 Thu 13 Dec 2012