A gated community and golf resort developed by Don Panoz, in May 1990, the Patterson city council received preliminary plans for Diablo Grande.

[5] In response to these claims, Diablo Grande created the Western Hills Water District to serve the community.

[4][6] Developer Donald Panoz envisioned Diablo Grande to consist of 5,000 to 10,000 homes, a resort hotel and spa, six golf courses, an equestrian center, vineyards, a winery and commercial properties, including a high-tech research park.

[7][8][9] After investing $120 million into Diablo Grande and the financial crisis of 2007–08 occurring, the investors of the community filed for chapter 11 bankruptcy on March 10, 2008.

[11] Diablo Grande's Legends golf course, designed by Jack Nicklaus and Gene Sarazen, was closed in March 2014 due to the drought in California.

[13] Also, instead of building homes spread along the hillsides, residential areas will be grouped together, leaving more open terrain and walking trails.

[14] It was also revealed that World International has outstanding tax bills on about half of its 340 parcels at Diablo Grande, totaling more than $6 million, and is looking for a new owner.

[18][19][20] According to the United States Census Bureau, the CDP covers an area of 5.1 square miles (13.2 km2), 99.99% of it land and 0.01% of it water.