Groundwater flow is now better monitored following new study

Accurate measurement of water flow has been for years difficult to perform, not to mention prediction of the water's path which is easily altered by the smallest soil details. Very fine details diverging the groundwater's flow from the straight sequential line is a phenomenon also referred to as "preferential flow" and may deadly affect crops that depend on moisture, as well as chemical spills requiring containment. The new study deals with some important obstacles in the monitoring of the "preferential flow".

The study on preferential flow was conducted in the Department of Ecosystem Science and Management of the Pennsylvania State University with Prof. Henry Lin as the lead researcher. When referring to preferential flow, Lin specifically says "Water bypasses a portion of the soil...and leads to faster and deeper water flow (in other areas) than what might be typically expected". This water flow actually affects and controls a variety of physical, chemical and biological functions of the soil, hence affecting the environment in many different ways. 

On a microscopic level, preferential flow may determine the amount of water, nutrients and various agricultural chemicals that are stored within the soil, as well as the soil's filtering capacity and landscape stability. Macroscopically, preferential flow may affect the entire water cycle, topography and vegetation. Lin's research comes to deal with important technological restraints in the measurement of preferential flow by using moisture sensors and a computer-monitored network. 

The moisture sensors were installed at different locations and depths from the ground level all the way to the bedrock. Initially, automatic periodic measurements were taken over a time span of 3 years, 175 precipitation events and 10 locations. Currently, data are gathered from 412 events over 6.5 years and 25 sites, allowing the team to perform a more detailed comparison of the seasonal data. Data processing revealed specific water patterns depending on small-scale elements, whereas according to Lin water flow patterns seem to depend on location, topography and time. With future research being crucial to the improvement of the study's findings, Lin hopes researchers worldwide will use these techniques, in order to better understand flow of water across different landscapes.