What if the water you drink every day looks perfectly safe but contains contaminants that could affect your health for years?

Millions of people in India depend on groundwater for drinking water. Yet contaminants such as fluoride, arsenic and nitrate can pose serious health risks that are often difficult to detect without testing.

In this episode of The Water Data Podcast, Dr Sunderrajan Krishnan , Executive Director of the INREM Foundation joins host Veena Srinivasan to talk about India's drinking-water quality crisis and what it will take to address it.

Dr Sunderrajan Krishnan is the Executive Director of INREM Foundation, an organisation working on water quality and public-health issues in India. His work connects groundwater science, community engagement and water governance.

In the conversation, they explore why groundwater contamination often goes unnoticed, how decades of water-treatment interventions have struggled with maintenance and adoption, and why community-led water testing can make a difference.

The conversation also examines how contaminated water, food and nutritional deficiencies can compound health risks among vulnerable communities. They discuss the role of reverse osmosis (RO) systems, the importance of safe local water sources and the challenges of making Jal Jeevan Mission deliver reliable, safe drinking water.

Finally, Sunder makes the case for lifeline water: a guaranteed minimum supply of high-quality water for everyone's essential drinking and cooking needs.

The Water Data Podcast is a talk show on the science, systems, and stories of water, hosted by Veena Srinivasan and produced by WELL Labs.

For all references and further readings related to the episode, visit https://welllabs.org/wdp-suderrajan-krishnan/

Subscribe to The Water Data Podcast on your favourite podcast app—and catch video episodes on the WELL Labs YouTube channel @welllabs.

Subscription links: Youtube, Apple Podcasts, Spotify, YouTube Music, Amazon Music, Audible, Castbox, and wherever you get your podcasts!

Recording by Team On productions. Video editing by Srisabari Varaguna Pandian. Graphics and artwork by Kanishka Goyal. Audio mixing and mastering by Vijay Doiphode. Podcast production and management by Vraj Acharya, Nabina Chakraborty and Pavan Srinath.

How does water that looks perfectly clean contain dangerous levels of arsenic? Even after decades of research and treatment technologies, why does arsenic exposure remain a drinking-water problem?

In this episode of The Water Data Podcast, hydrogeologist Prof. Abhijit Mukherjee joins host Veena Srinivasan to trace the arsenic story across the Bengal and Ganga-Brahmaputra aquifer systems.

In the conversation, Veena and Abhijit explore how arsenic naturally occurs in sediments, why the geology and geochemistry of the Bengal Delta allow it to enter groundwater, and how microbial activity, iron minerals, and changing chemical conditions underground influence its mobilization.

The conversation also examines how large-scale pumping can change groundwater flow and potentially mix water between aquifer layers, making apparently simple rules about "safe" and "unsafe" groundwater much harder to apply.

Abhijit argues that arsenic treatment itself is not necessarily the biggest challenge. Filters need to be maintained, contaminated filter media must be safely disposed of, drinking-water sources must be monitored, and solutions have to work after researchers and engineers leave.

Veena and Abhijit also discuss arsenic in irrigated agriculture and the unequal vulnerability to exposure. This episode asks a larger question: when the science of a water problem is reasonably well understood, what prevents that knowledge from becoming safe water for everyone?

The Water Data Podcast is hosted by Veena Srinivasan and produced by WELL Labs.

The Water Data Podcast is a talk show on the science, systems, and stories of water, hosted by Veena Srinivasan.

For all references and further readings related to the episode, visit https://welllabs.org/wdp-abhijit-mukherjee/

Subscribe to The Water Data Podcast on your favourite podcast app—and catch video episodes on the WELL Labs YouTube channel @welllabs.

Subscription links: Youtube, Apple Podcasts, Spotify, YouTube Music, Amazon Music, Audible, Castbox, and wherever you get your podcasts!

Recording by Nabina Chakraborty and Nanditha Gogate. Video editing by Srisabari Varaguna Pandian. Graphics and artwork by Aparna Nambiar. Audio mixing and mastering by Vijay Doiphode. Podcast production and management by Nabina Chakraborty and Pavan Srinath.

Can we measure evapotranspiration from space? And when a satellite produces a map of crop water use, how certain are those numbers?

Dr. Gilles Boulet joins host Veena Srinivasan for a deep dive into one of the most important and difficult-to-measure components of the hydrological cycle: evapotranspiration.

Evapotranspiration, or ET, combines evaporation from soil with transpiration through vegetation. In many semi-arid landscapes, it accounts for most of the water leaving the land surface. However, measuring ET across individual farms, irrigation commands, and entire watersheds is remarkably difficult.

In this episode, Gilles and Veena unpack what satellites actually observe, from vegetation and radar signals to land-surface temperature. They also discuss how scientists turn those observations into estimates of evapotranspiration.

They explore the role of flux towers and scintillometers, why satellite ET products contain uncertainty, and the differences between contextual and physics-based modeling approaches.

The conversation also looks ahead to TRISHNA, the Indo-French thermal-infrared satellite mission that aims to provide much more frequent land-surface-temperature observations at field-relevant spatial scales.

Additionally, the conversation answers questions regarding how better ET observations could help irrigation departments and groundwater agencies understand where water is actually being consumed, and whether we are close to producing reliable, near-daily maps of agricultural water use.

Dr. Gilles Boulet is a senior scientist at IRD and works with the Indo-French Cell for Water Science at the Indian Institute of Science, Bengaluru. His research focuses on land-surface processes, remote sensing, evapotranspiration, and field instrumentation.

The Water Data Podcast is a talk show on the science, systems, and stories of water, hosted by Veena Srinivasan.

For all references and further readings related to the episode, visit https://welllabs.org/wdp-gilles-boulet/

Subscribe to The Water Data Podcast on your favourite podcast app—and catch video episodes on the WELL Labs YouTube channel @welllabs.

Subscription links: Youtube, Apple Podcasts, Spotify, YouTube Music, Amazon Music, Audible, Castbox, and wherever you get your podcasts!

Recording by Nabina Chakraborty, Vraj Acharya and Nanditha Gogate. Video editing by Srisabari Varaguna Pandian. Graphics and artwork by Aparna Nambiar and Kanishka Goyal. Audio mixing and mastering by Vijay Doiphode. Podcast production and management by Nabina Chakraborty and Pavan Srinath.