Pop superstar Lady Gaga is helping to promote and preserve California's Hearst Castle by donating $250,000 (£156,250) to the estate's foundation in exchange for the chance to film an art project at the architectural landmark.

The Poker Face hitmaker will take over the former home of media mogul William Randolph Hearst, which is now a state park, for three days this week (begs10Feb14) for the secret shoot.

Details of the project have been kept under wraps, but generous Gaga has agreed to use her time at the venue to record a public service announcement for the Hearst Castle Preservation Foundation, educating fans about the importance of water conservation.

She has also signed up to cover the costs for a $25,000 (£15,625) water stabilisation study to allow officials at the luxury home to explore ways to improve the property's water supply system.

Hearst Castle was donated to California state officials in 1957, six years after tycoon Hearst's death, and has since been preserved as a National and California Historical Landmark.