ROCKLIN, Calif. -- An agreement has been reached to help preserve sacred Native American ground near Rocklin, the city and organizations close to the plan said Thursday.

The United Auburn Indian Community said it has contracted to buy 154 lots in Clover Valley, according to the city of Rocklin and Clover Valley Partners.

The area would protect sacred sites from development.

The Wildlife Heritage Foundation helped negotiate a long-term open space management contract, the organizations said, which will increase open space in Clover Valley to 406 acres.

"The Conservation Easement will ensure that the sites protected by the approved project, and deemed sacred by the United Auburn Indian Community, will be retained forever in their scenic natural valley setting," Jessica Tavares, chairwoman of the United Auburn Indian Community, said. "In addition, our tribe will also construct a cultural center where people of all ages will be able to gain a greater understanding of the rich cultural history of the area."

Last February, Rocklin voters approved the development of more than 500 homes in Clover Valley.

Measure H passed with 52.85 percent of the vote.

The United Auburn Indian Community said before the election that it planned to buy about 65 acres in Clover Valley if the development was approved.

Clover Valley is a historic, underdeveloped area between Rocklin and Loomis.