Mayfly DIY Water Quality Monitoring

Mayfly Sensor Stations provide real-time stream data at low cost

Mayfly water-quality logger
Mayfly water-quality logger

Scientists, anglers and interested public throughout the country rely on USGS gaging stations for real-time streamflow and water quality data. Often these stations are located near the mouth of larger rivers, so may not characterize what is happening in smaller coldwater trout streams. Now, rapidly emerging technologies in open-source electronics are allowing volunteer groups to collect valuable real-time water data. Developed by Stroud Water Research Center, the Mayfly Sensor Station is a low-cost, easy-to-use water monitoring station designed to collect continuous data, often taking measurements every five minutes. Data are then uploaded to an online database via cellular signal for real-time access to current stream conditions.

Though the stations have not been vetted for USGS-caliber data, stations co-located with USGS stations track closely and provide data that is highly useful for the typical needs of TU and our partners.

The Mayfly Sensor Stations are solar powered and can be connected to a variety of environmental sensors. TU has deployed stations measuring temperature, depth, conductivity and turbidity. Data are sent from the station to an online database via 4G cellular signal, though there are other data communication methods that can be explored in areas without 4G availability.

Mayfly logger station, installed with sensors and staff gauge. Stroud WRC photo

This effort is part of EnviroDIY, a community of do-it-yourself environmental monitoring. Founded by Stroud, the community collaborates on the development of open-source hardware and software solutions for observing the environment, with a focus on water monitoring. The group is working to support an explosion of real-time monitoring by creating monitoring resources that are low-cost, easy to learn and easy to use.

TU is now building the necessary capacity to be a key service provider, bringing this technological capacity to our chapters and partners throughout the country. This includes building the stations in-house and providing training and technical support to volunteer groups adopting the technology. Once volunteers have received training on the requirements for station installation and ongoing maintenance, the Mayfly Sensor Stations have the potential to dramatically expand the availability of quality real-time water data, and TU is poised play a key role in identifying areas where there is a need for this type of data and supporting groups to adopt and deploy stations. Contact Jake Lemon, TU Eastern Angler Science Coordinator at or Matt Barney, TU Senior Programmer at with questions regarding this program.