Assessing age of groundwater to determine resource availability
Groundwater discharge that flows into the Upper Colorado River Basin varies in response to drought, which is likely due to aquifer systems that contain relatively young groundwater, according to a new U.S. Geological Survey study published in Hydrogeology Journal.
Spring sampling location along Little Sandy River in southern Wyoming. Groundwater discharge that flows into the Upper Colorado River Basin varies in response to drought, which is likely due to aquifer systems that contain relatively young groundwater, according to a new US Geological Survey study.
The Colorado River and its tributaries provide water to more than 40 million people in seven states, irrigate more than 5.5 million acres of land, and support hydropower facilities. More than half of the total streamflow in the UCRB originates from groundwater. Reductions in groundwater recharge associated with climate variability or increased water demand will likely reduce groundwater discharge to streams.
This is the first study that examines the short-term response of groundwater systems to climate stresses at a regional scale by assessing groundwater age. USGS scientists determined the age of groundwater by sampling the water flowing from nineteen springs in the UCRB.
Age-tracing techniques can assess how long it takes groundwater to travel from the time it enters the aquifer system as precipitation to when the groundwater exits to springs and streams. Scientists compared eight of the springs with historical discharge and precipitation records with the groundwater age to better understand how aquifers have responded to drought. These findings helped scientists understand the variability and timing of groundwater discharge associated with drought.
"About half of the springs analyzed in the Upper Colorado River Basin contained young groundwater, which was surprising," said USGS scientist and lead author of the study John Solder. "These findings suggest that shallow aquifers, which are more responsive to drought than deeper systems, may be significant contributors to streamflow in the region."
Results show that if springs contain mostly older water, groundwater discharge is less variable over time and takes longer to respond to drought conditions. Springs that contain predominately young water, around 80 years old or less, are more likely to vary seasonally and respond rapidly to drought conditions. These results indicate that young groundwater resources are responsive to short-term climate variability.
"Sampling 19 springs in a very large basin is just the start, and further studies are needed to better understand the groundwater resources of this specific region," said Solder. "Determining groundwater age has promise in predicting how these systems will respond in the future and allows us to assess resource vulnerability where no historical records are available."
This study was funded by the USGS National Water Census, a research program focusing on national water availability and use at the regional and national scales. Research is designed to build decision support capacity for water management agencies and other natural resource managers.
Jennifer LaVista | EurekAlert!
NASA examines Peru's deadly rainfall
24.03.2017 | NASA/Goddard Space Flight Center
Steep rise of the Bernese Alps
24.03.2017 | Universität Bern
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy