Xylem’s YSI introduces groundbreaking technology for continuous nitrate monitoring

Xylem’s YSI introduces groundbreaking technology for continuous nitrate monitoring

New NitraLED solution requires 98% less power than traditional systems
Nitrate pollution in water can have far-reaching negative impacts on public health, the environment and the economy. Traditional methods for measuring nitrogen, however, are expensive, resource and energy intensive, and only allow periodic measurements that don’t give a full picture. Xylem’s YSI brand is helping change this with its groundbreaking and affordable EXO NitraLED technology.

EXO NitraLED is the world’s most accessible UV nitrate sensor, built with state-of-the-art LED technology, for long-term nutrient monitoring. With seamless integration into any EXO Sonde from YSI, this sensor simplifies and dramatically reduces the cost of unattended nitrate monitoring for point and non-point source pollution in freshwater environments.

The new UV nitrate sensor requires 98 percent less power than traditional lamp-based systems, and it has been designed by Xylem engineers to be small enough to fit into the palm of your hand.
To put Xylem’s new EXO NitraLED technology in context, we spoke with three experts at YSI to learn about the importance of nitrate monitoring, the current challenges in collecting nitrate data, and how Xylem’s technology is breaking new ground to solve them.

Why monitoring for nitrogen is important

The three main sources of nutrient pollution are agriculture, animal manure and effluent discharge from wastewater treatment facilities. While nutrients and fertilizers are essential for an abundant food supply, crops take up only 40 percent of the nitrogen supplied each season, leaving the rest to drain downstream.
“One of the most critical water quality parameters that we can measure is our nutrient levels because of the drastic impact they can have downstream,” says Lisa Landry, Technical Sales Representative, YSI. “These nutrients, primarily nitrogen and phosphorus, are fundamental components of living organisms. However, too much nitrogen and phosphorus can dramatically alter aquatic environments.”
Landry says that one of the biggest problems with high nutrient loads and high nitrate levels is eutrophication, when bodies of water become enriched with nutrients, leading to harmful algal blooms, dead zones and fish kills. The EPA in the United States has shown that excessive nutrients impair over 15,000 water bodies. And over 100,000 miles of streams have a high nutrient load. It’s also a global problem. Over 65 percent of the Atlantic coast of Europe has symptoms of eutrophication and high nutrient or high nitrate levels.
“It’s a huge environmental issue,” says Landry. “These high levels can drive the growth of harmful algal blooms, which will have a significant impact on both ecosystems and economics. We also can't ignore the health impacts high nitrate levels can lead to in our drinking water. Whether our drinking water is from source water reservoirs or groundwater, high nitrate levels can undoubtedly impact our overall health.”

Current challenges with collecting nitrate data

“With all of these terrible environmental events happening around us, scientists want to tackle this nutrient pollution issue head-on more than ever before – but doing so involves many complexities,” says Kerry Caslow, Outdoor Water Monitoring Specialist, YSI. “While phosphorus tends to bind to sediment, nitrate is completely soluble in water, making the challenge of nitrate control a lot more complicated than that of phosphorus. So, while we all want to get our chemistry sets out and create something to fix this problem, at the end of the day, we're just not able to for a few reasons.”
Some of these reasons, Caslow says, include shrinking budgets for water monitoring and the large geographical areas that need to be covered. Monitoring groups often don’t have enough personnel or equipment, leading to weekly or monthly sampling of data instead of continuous monitoring. Equipment costs are another critical issue, as well the challenge of setting up monitoring sites.
“Nutrient monitoring can be costly,” Caslow says. “There’s no doubt at all about that. Lamp-based nitrate instruments currently available can cost nearly the same as a new car – or more! And other components also must be purchased to make these continuous monitoring instruments work. Many of these systems run off of an external battery, which means you need a shelter to store it all in. Plus, you're going to need a solar panel and a regulator, a way to record and transmit that nitrate data, and much more."

The future of nitrate monitoring programs

“We know that tons of funding are spent each year to reduce nutrient loads and pollution in our watersheds,” says Lisa Landry, Technical Sales Representative, YSI. “Having an expansive network of continuous nitrate sensors would allow us to guide and implement these projects and validate if they're working and what we could do better.”
Landy says that improved nutrient load estimates and enhanced coastal monitoring are also needed to better understand the relationship between eutrophication and harmful algal blooms in our coastal waters.
“Can we prevent fish kills and dead zones, or at least shrink the affected area? Possibly, if we had more data! This would also decrease the socioeconomic impacts caused by these events.”

Groundbreaking nitrate monitoring technology

With the state-of-the-art EXO NitraLED technology, Xylem’s YSI engineers have developed a way to make continuous nitrate monitoring affordable. One way this has been achieved is by seamlessly integrating the new UV nitrate sensor with YSI’s EXO Sondes. EXO is YSI’s industry-leading multiparameter sonde, with tens of thousands of systems deployed worldwide.
“Combined with an EXO Sonde, this sensor simplifies and dramatically reduces the cost of long-term unattended nutrient monitoring for point and nonpoint source pollution in freshwater environments,” says Zack Henderson, EXO Product Manager for Environmental Monitoring Systems, YSI. “This is not a new sonde. Instead, this is a sensor designed to work with all existing EXO Sonde models.”
The sensor’s seamless integration and affordable price point allows organizations to easily upgrade their water quality monitoring sites to collect continuous nitrate data, say Henderson.
“Most other UV nitrate sensor manufacturers have taken a laboratory spectrophotometer and retrofitted it for use in the field,” says Henderson. “And with that, you see the increased prices. Our sensor has been designed from the ground up for field monitoring, not ‘frankensteined’ from previous technology.”
EXO NitraLED is purpose-built for outdoor freshwater monitoring and thus operates much more efficiently than existing UV sensors using xenon or deuterium lamps, which suffer from high power requirements and are bulky and expensive. Xylem’s new UV nitrate sensor requires 98% less power than traditional lamp-based systems.
“Recent advances in UV LED technology have enabled our Xylem engineers to miniaturize the light source, thus mitigating shortcomings associated with traditional lamp-based instruments commercially available in the past. Thanks to the truly innovative use of UV LEDs, YSI has been able to produce an optical nitrate sensor that fits in the palm of your hand.”
“We’re committed to expanding the EXO platform, and EXO NitraLED is no doubt our most exciting development to date!” says Henderson. “Now, thousands of EXO monitoring sites around the world can be equipped with optical nitrate sensing. EXO NitraLED can help monitoring groups lower costs while continuously collecting accurate and reliable data.”

Commitment to sustainability

The new EXO NitraLED sensor is one example of Xylem’s overall commitment to sustainability. Learn more about how Xylem is helping strengthen the environment, the global economy and society in our Sustainability Report.