Powder River Basin Recharge Estimation Project

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Soil Moisture

Measurements of soil moisture were made by utilizing the ECHO-TE probes manufactured by Decagon. The ECHO probes measure the dielectric constant of the soil via capacitance methods which can then be converted into volumetric water content values. ECHO probes generally do not require any site specific calibration provided unless there is a significant solute presence. We chose to measure the soil moisture states using the ECHO at the two field sites (Padlock Ranch and Forks Ranch). At each of theses locations a soil pit was dug about 45 inches deep.  A total of five probes were inserted at depth of 2", 4", 8", 20", and 40". The soil pit was then backfilled with care to approximate the natural soil density. Unfortunately, it was impossible in practice to place the sensors at equal depths across all soil pits.
Soil Pit at Padlock Ranch site   
echo te sensor
ECHO-TE sensors
compaction 1
Refilling and compaction
compaction 2
Refilling and compaction   
Data logger
soil pit
Soil Pit at approximate natural soil density    
Additional soil moisture measurements were made using Time Domain Reflectometry (TDR) and Water Content Reflectometer (WCR) probes manufactured by Campbell Scientific. A total of five TDR probes were inserted at depth of 2", 4", 8", 20", and 40" at the Forks Ranch site. Four WCR were placed at 2", 4", 20", and 40" at the Forks Ranch, while a single WCR was placed at the Padlock Ranch at 8".
Soil Pit at Forks Ranch site
TDR probes
ECHO-TE  probes
WCR probes
Compaction process
Burying sensors
forks soil
Restoring natural vegetation
final site
Final Site

Updated: 10/09/2006 (FLO, KAP).

Site Description

Eddy Covariance

Soil Moisture




UW College of Engineering

Dept. of Civil & Architectural Engineering

Univ. of Wyoming Ruckelshaus Institute of Environment and Natural Resources

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