Providing daily letter grades from A to F, Heal the Bay’s Beach Report Card app makes it easy for California beachgoers to plan their visits. Most west coast beaches sample the water once a week which, when combined with 24 to 48 hour turn-around time for test results, makes the data almost immediately out of date.

Unsafe levels of water-borne bacteria often clear up within a day, which is why Heal the Bay believes its “nowcasts” are so important. Bacteria can cause skin rashes, ear and chest infections and stomach bugs. Developed by UCLA, Stanford University and Heal the Bay, the app currently covers five beaches along the west coast of the United States between April and October. Heal the Bay plans to continue expanding the numbers of beaches covered by the app each summer.

Crowdsourcing is an efficient way to gather data from large public spaces, and crowdsourced water management projects are becoming more common. Jellyfish sightings can be logged with this app, and surfers are able to gather climate change data via smart board fins. How could crowdsourcing combine with scientific analysis to strengthen local apps?