BROOKLYN - The New York City Department of Environmental Protection (DEP) has launched its "Water-on-the-Go" program again for the summer.

The program, which promotes hydration, will place portable water fountains at 20 different locations throughout the city.

The DEP also created an iPhone app to locate the fountains and says that people who check in using Foursquare will be entered to win a water bottle.

Official say that last year, 200,000 people used the portable fountains.