Work is already underway to double the size of the Mayo Clinic campus to more than 3 million square feet near Loop 101 and 56^th Street in north Phoenix. Now, Mayo is looking to expand again.

In December 2021, Mayo bought nearly 228- acres of land next to its existing campus. That’s where it wants to create what’s being called “Discovery Oasis.” Phoenix Economic Development Director Chris Mackay said it would be similar to “Discovery Square” across from Mayo’s original campus in Rochester, Minnesota.

“It’s about 16 blocks of life sciences, businesses and partners to Mayor and other types of amenities and industries related to Mayo,” she said. “Mayo is proposing to build a minimum of half a million square feet, not less than $250 million in capital investment and creating 2,000 high wage jobs on this expansion site.”

Mackay said the site would be home to early and later stage health care, life sciences and technology companies that support Mayo’s work. If the City Council approves, Phoenix will reimburse Mayo up to $40 million for installing new public infrastructure and drainage work.

A report from the city’s economic development department said: “Mayo has been a strategic partner of the City of Phoenix as it works to attract life science and health technology leaders, and jobs, to the community. The creation of Discovery Oasis will further accelerate these efforts as companies are attracted to being co-located with Mayo as a top-ranked research and patient care organization.”

The report lists the following public infrastructure improvements and drainage solutions estimated to cost $40 million that will need to be installed by Mayo:

• Construction of the north half of Mayo Boulevard along project frontage including streets, curb, gutter, sidewalk, and landscaping;
• Construction of the east half street of 56th Street frontage including street, curb, gutter, sidewalk, and landscaping;
• Reconstruction of the interim traffic signal located at the intersection of Mayo Boulevard and 64th Street, unless developed sooner by others;
• Additional public street improvements and traffic signal infrastructure as required by the approved traffic impact analysis;
• Construction or redevelopment of roadway striping or resurfacing to accommodate the restriping;
• Contribution of $4.7 million toward the construction of the 64th Street improvements, including the bridge over the Reach;
• 16-inch water main extension within Mayo Boulevard, from 56th to 64th streets;
• Distribution water main extension along 64th Street north of Mayo Boulevard;
• Connection of the main within 64th Street connecting to the existing 12-inch main within Mayo Boulevard;
• Construction of water main extensions within the new public right-of-way adjacent to, or incorporated in, the project;
• Construction of new fire hydrants located in the public right-of-way;
• Construction of new sewer mains or upsizing of existing sewer mains located in public right-of-way;
• Improvements related to public transit including bus stops, bus shelters and enhanced street improvements to accommodate for public transit; and
• Construction of the ultimate 100-year storm event box culverts along both Mayo Boulevard and 64th Street.