If you’re looking up into the valley skies this week and see a large, oddly shaped device hanging from a helicopter, don’t worry.
This is part of a research project to map underground water reserves.
Beginning Monday, overflights are expected in areas west and south of Fresno – including Fowler, Kingsburg, Lemon Cove, Orange Cove, Orosi, Parlier, Piedra, Reedley, Sanger, Selma, Woodlake.
This high-flying technique has already been used in California and has been shown to provide useful information that can be used to better manage natural resources.
Why target the Central Valley?
Stanford researchers are leading the project. The goal is to better understand how groundwater systems in the Central Valley receive water from the Sierra Nevada mountains.
The specific question of interest in their work: Where are the recharge pathways – areas of coarse, permeable material – along the eastern edge of the Central Valley, which can move surface water and/or groundwater from the Sierras into the groundwater systems of The valley ?
The warm colors show the regions where there are coarse-grained sands and gravels. These materials can retain a large amount of water and displace a large amount of water. These are the colors the researchers are looking for in the new study – hoping to find the sand and gravel pathways of the Sierras that carry water from great depths down the valley. (Courtesy of gemcenter.stanford.edu/research)
“Spider Web” electromagnet array
The scientific equipment is suspended about 100 feet below the helicopter in a “spider’s web” network and is designed to map geological structures and groundwater resources down to about 900 feet below ground.
The helicopter will be flown by specially trained low-flying pilots and their flight path is designed to obtain the best available underground data.
Researchers have successfully used the airborne electromagnetic method in the past in the area.
The helicopter strategy has been used all over the world. (Photos courtesy of SkyTEM)
No data collection on residential areas
Since data can only be collected on open spaces, no data collection will be conducted on residential areas, livestock feeding operations or other buildings.
After the flights, Stanford University will use the data to develop a better understanding of recharge in the region. An update of their work will be available at https://gemcenter.stanford.edu/research-projects.