Since the release of Pokémon GO in 2016, developer Niantic organizes special events to get more players out into the world, such as this year’s Earth Day Cleanup event. An organization inspired by the game found a way to use the concept of having people explore their areas in order to monitor streams.

Stream Tracker is a project conducted by citizen scientists who are trying to map out streams across the country. Maps will show the location of larger streams that constantly flow, but there are other smaller waterways that become streams when it rains. The project’s goal is to fill in the gaps not shown in maps in order to predict streamflow forecasting to prevent any risk to water supply or flooding, as well as give more information about an area for future land use. The idea for the project came when two hydrologists in Colorado saw people walking around playing Pokémon GO.

“There [were] all these people walking around with mobile phones looking for Pokémons and we were trying to understand streams,” hydrologist Stephanie Kampf told NPR Friday. “We thought, ‘Wouldn’t it be great if those people walking around were actually collecting data that would be useful?’”

Kampf and fellow hydrologist Kira Puntenney-Desmond requested funding from NASA for the Stream Tracker project. Those who want to participate need to simply join the project, download the Maps.Me navigation app and the CitSci app, and go out into the field to look for streams. The project’s website has a file that will give points of interest to the navigation app. Once a stream is found, the CitSci app can be used to record basic info such as weather conditions and whether there is a flow or not.

Stream Tracker started last year and has more than 100 volunteers who completed thousands of observations on hundreds of sites. So far, the project has people in California, Utah, Colorado, Arizona, West Virginia, Maryland, and Pennsylvania.

This is not the first time the popular Pokémon catching mobile game was an inspiration source. An app in China used augmented reality to have users find virtual packages in the real world, and an episode of The Simpsons had a scene featuring the game.