“If there is no water, there is no life. Civilizations began where people found water,” said Venkat Sridhar
“Water is the crux of everything,” Venkat Sridhar says.
It’s the lifeblood for agricultural production of the fertile land that rims the Chesapeake Bay. It’s the engine of an economic boom along the Mekong River where hydro dams are a growing issue. And it’s the elusive resource in Sridhar’s hometown in India, where people are grappling with “Day Zero,” when millions ran out of drinking water.
It was this complexity — compounded with the growing challenges of managing water in a world where competing interests are vying for the world’s most precious resource — that inspired Sridhar to become a water resources engineer and continues to drive his passion for improving water management around the world.
“If there is no water, there is no life. Civilizations began where people found water,” said Sridhar, an associate professor in the Department of Biological Systems Engineering, which is in both the Virginia Tech College of Agriculture and Life Sciences and the College of Engineering. “We need technologies to conserve and improve the management of water resources, which is what drove me to become an agricultural engineer.”
Using big data to create models to manage water in a changing global climate, he studies water resources all around the world, from India to Vietnam to right here in Virginia
Sridhar develops complex mathematical models that are built by layering and weaving together existing data sets on top of each other, with information gleaned from NASA, the National Oceanic and Atmospheric Administration, and others, to predict future precipitation, temperature, snowmelt, streamflow, soil moisture, droughts, and floods. Assembling the big datasets, which can be as large as 40 terabytes in size, can take up to two years for him and his graduate students to crunch, but the wait is worth it. Sridhar partners with Virginia Tech’s Advanced Research Computing program to do most of the analysis.
Sridhar has ongoing projects in 12 countries. He was a Fulbright Scholar in India, the co-leader on a NASA-funded project to study water use in Mekong Basin, and is an adjunct faculty in the prestigious Indian Institute of Technology Roorkee. He also serves as the American collaborator for the USAID Partnerships for Enhanced Engagement in Research project with Tamil Nadu Agricultural University to evaluate adaptation pathways for agricultural water management in the Bhavani Basin, India.
Although he works in places around the world, he also studies water resources in Virginia. His work on the Chesapeake Bay watershed involves looking at the availability of water in the region and how it changes over time. Sridhar is examining the entire water budget for the region, incorporating how much rain falls in certain parts of the sub-basin and how water use has changed the amount of water available to farmers in the area, who rely upon the streams and rivers of the Chesapeake Bay Watershed. Agriculture is the number one private economy in the state with an annual economic impact of more than $70 billion. Many of the farmers in the state rely upon the streams and rivers within the Chesapeake Bay watershed.
His models build a picture of what precipitation will look like in the future and allow water managers and farmers to adapt to the changing streamflow magnitudes and intensities. For instance, in the Norfolk region, an increase of up to 50 percent in flood magnitude is expected by the middle of this century. The Chesapeake Bay region might see increases in precipitation between 5 and 8 percent towards the second half of this century and streamflow up to 6.3 percent. Some regions within the Chesapeake Bay watershed also see decreases in precipitation and up to a decrease of 22 percent in stream flows. A lot is dependent on the location and model’s ability to capture historic climate but the accuracies are getting better in recent times.
On the other side of the world, Sridhar is using the same modeling principles to help residents of Chennai, India, deal with their water crisis.
The city sits on the eastern shore of India and has historically relied on seasonal monsoon rains as its water source. The region is one of the largest cities of the country but has been beset by a water emergency due to drought in recent years. Poor retention and storage, reduced recharge, and lack of water management policies have allowed the water to flow straight into the sea, rendering it unavailable for residents. This has led to the overuse of groundwater, depleting the already shrinking aquifers. Changing climate has compounded the issue, altering the flow of monsoon water that locals relied upon.
“This shift in rainfall and the problems that loom large are triggered by the climate crisis,” Sridhar said. “It’s all related – humans and livelihoods and science and engineering.”
This resulted in a crisis that made international headlines when officials this summer declared “Day Zero” because water no longer flowed from the taps.
Sridhar has been developing a model to predict how this confluence of events will play out in the future. This was part of the work he did when he was a Fulbright Scholar in India last year when he provided training to young researchers to evaluate climate change scenarios in the context of quantifying the exposure and sensitivity of rainfall and irrigated agricultural systems.
Water managers will be able to use this information to build better infrastructure to more adequately deal with the impacts of changing climate and water use.
Sridhar is a strong advocate for teaching others how to implement and use his water modeling techniques.
Two doctoral students came from Warangal, India, this winter to learn how to develop these models and implement them in India. Sridhar will be teaching a workshop on water management in collaboration with NIT Warangal and several other institutions in the state of Odisha.
Additionally, Sridhar is doing in the Mekong Region to study the water-energy-food nexus using a combination of models and large datasets. His team of post-doctorate and graduate students are investigating drought, salinity, and water management and the role of human activities in compounding these problems for in the Mekong River basin
“Our very future depends on having clean, reliable water sources,” Sridhar said. “I believe we can use big data and modeling to help us ensure we have the water we all need.”
Written by Zeke Barlow