From NBC4, where you can read the full story:

Ballou High School’s famous marching band played Pharrell Williams’ hit song “Happy” — and then the star himself walked through the door.

Pharrell and D.C. Mayor Muriel Bowser announced Tuesday that the Something in the Water festival will be held on Independence Avenue, on the National Mall, this Juneteenth weekend, June 17-19.

Bowser promised “three days of excitement” as festivals return to the District.

The eclectic festival lineup includes Pharrell, Chloe X Halle, Calvin Harris, Dave Matthews Band, Lil Baby, Lil Uzi Vert, Run the Jewels, T.I. and Usher. The go-go musicians Backyard Band, Rare Essence and Sound of the City also will perform.

There also will be “some people we can’t announce,” organizers said.

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