Lady GaGa has joined a campaign to urge Californians to conserve water during the state's worst drought in decades.

In a new video for the Save Our Water campaign, the Poker Face singer reveals she learned all about California's water shortage during a recent trip to the state.

She concludes her message by stating, "Do your part to save water."

The video comes six months after Governor Jerry Brown called for a 20 per cent cut in water usage. Updated results suggest conservation fell short of that figure.