Xylem report shows how sensors are helping water sector blaze carbon-cutting path

With some 80 water and wastewater utilities worldwide setting net-zero and climate-neutrality targets, a new report suggests that the water sector could become one of the fastest to decarbonize, using existing technologies at low cost.

In its report, Net Zero: The Race We All Win, global water technology company, Xylem, highlights success stories about water managers worldwide reducing emissions and making infrastructure more resilient to climate change, while also providing a roadmap for utilities that may still need a pragmatic plan for action.

“This paper and action show how leading water utility managers are delivering real progress toward net-zero goals,” announced Patrick Decker, president and CEO of Xylem, in a statement. “And these examples show how quickly and affordably they are doing it, while optimizing their overall operations. The technology exists to address these challenges, and the time to make a difference is now,” he added.

Water infrastructure accounts for approximately 2% of global greenhouse gas (GHG) emissions — nearly the same as the global shipping industry, the report states. A medium-size water utility offering both clean water and wastewater services can produce the equivalent of 42,000 tons of CO₂ emissions annually from energy usage alone — the same as 150 commercial flights from Paris to New York City.

To reduce this impact, Xylem has found that more and more water utilities are taking steps such as realistic, measurable GHG reduction targets; optimizing energy and resources across networks; embedding net-zero goals in capital planning; and moving from treatment to resource recovery.

Among the success stories highlighted in the new report is that of South Bend, Indiana, where the sewage system had struggled in the face of major weather events. The city installed a real-time monitoring system of more than 120 sensors located throughout its urban watershed, and then expanded the sensor network to be part of a system that controlled the pumping system and valve actuators to react in real time.

Using Xylem Wastewater Network Optimization, the city reduced combined sewer overflow volume by more than 80%. The city avoided building new grey infrastructure and eliminated the embedded carbon, delivering system performance, capacity utilization, and environmental gains more than a decade ahead of schedule.

Now, South Bend’s network adapts to sudden wet-weather events by shifting excess flows to underutilized parts of the network.

“While the headline figure of our work was that the city has saved approximately $500 million in capital work savings, the impact on our carbon footprint should not be overlooked,” South Bend Public Works Representative Kieran Fahey explained in the report. “By avoiding a large construction project and prolonging the life of our infrastructure through smart technology, we have made a major impact in reducing our carbon footprint.”

The report also highlights the work of one of Germany’s largest wastewater companies, EWE WASSER GmbH, which serves some 400,000 customers. The company learned that aeration accounts for more than 50% of its annual energy use, so it developed virtual sensors to estimate incoming carbon, nitrogen, and phosphorus loads, optimizing aeration and chemical inputs at each point of the process. Xylem provided a real-time digital twin of the entire plant so that each process receives optimal aeration and chemical inputs to match the needed chemical and biological oxygen demand.

The treatment plant has since shown a 30% reduction in aeration energy usage, corresponding to 1.1 million kWh annually, or enough energy to power some 275 homes for a year.