In Downtown Brooklyn, Fulton Street–the neighborhood’s commercial thoroughfare–is closed to cars. Technically, at least. Fulton is designated as a bus-only street, but around 3,000 cars each month use the corridor illegally. This creates issues for the buses and their 20,000 daily riders, which rely on clear lanes to make up time on their otherwise crowded routes, and for the pedestrians and cyclists that also depend on the road being car-free for a safer trip. A nonprofit in the area wanted to end the illegal car traffic on the street for a while but didn’t know where exactly the traffic was coming from. A startup called Numina helped them discover through data-gathering technology that most cars were illegally coming from Flatbush Avenue, which helped the nonprofit implement monitoring measures that have made sure the street stays car-free. Why does any of this really matter? Because it’s one of the first examples where “smart cities” technology is actually being used in a city. The issue with “smart cities” technology is that it can’t be proven useful until it gets up and running in the urban landscape. Now in Brooklyn, three startups are getting the chance to prove their technology can optimize the flow of the city and help city planners make better decisions. Have a look here how smart city tech is starting to pay dividends in Brooklyn.