Read more in the Promising Prototypes of 2025
Photo: Whitney Knopp / Virridy
The presence of E. coli in water suggests fecal contamination and could be a sign that water treatment measures have stopped working properly. The startup Virridy is developing an autonomous, Internet-connected sensor called Lume that detects the bacterium and immediately send alerts when it has a positive result. Virridy spun out of the University of Colorado Boulder and is supported by the US National Science Foundation and Blues wireless.
“We anticipate that it can be used for risk monitoring of drinking water and recreational water use,” Whitney Knopp at Virridy told E4C by email. “The water quality data gathered by the Lume
sensor provides insight into the effectiveness of chlorination and treatment for drinking water, ensuring that communities are consuming water of adequate quality. In the future, it
will also act as an indicator of system functionality, identifying when boreholes are not operating and may need repairs.”
The Virridy team is testing the sensor in Boulder Creek near the campus where it originated, and in drinking water supplies in Rwanda and Kenya, with further testing planned in Oregon in collaboration with the US Environmental Protection Agency and Oregon State University.
In Isiolo, a community in northern Kenya, Virridy’s team has installed the sensors in the distribution system of a borehole supplying chlorinated drinking water. The startup has also installed the sensors in drinking water supplies treated by Lifestraw filters that provide clean drinking water to school children in Rwanda. The sensors monitor the untreated water for contamination.
“The next steps are to continue testing to strengthen the device’s sensitivity and refine the design of the hardware. We estimate that it may be ready for commercial use in two to three years,” Ms. Knopp says.
There is competition in the E. coli sensor market, but Lume differentiates itself. These devices are built for long-term, continuous remote use. They adapt to conditions over time through a machine learning model, reducing the need for maintenance and cleaning. And they are inexpensive, using low-cost components such as LEDs and silicon photomultipliers, the Lume team said in a group email to E4C.
“The Lume possesses a unique capacity to provide beneficial insights on water quality to stakeholders including those engaged in land and water conservation, citizen scientists, and operators of rural drinking water systems. We envision deployment globally, expanding to a large network of water quality monitoring,” Ms. Knopp says.
Virridy tries to keep the sensor’s cost down through decisions about design and materials, but its cost may also be offset by carbon credits. Providing safe drinking water is one way to generate carbon credit revenue.
Virridy is seeking Lume beta testers.
For more, see Virridy’s Website: virridy.com
