CAVE CREEK - Cave Creek built a water storage tank partly on land it doesn't own and now plans to buy the property for $1.2 million.

The town had consent from the property owner to build a "small portion" of the 1.1-million-gallon tank outside its boundaries, said Town Utilities Manager Jessica Marlow.

Herb Thompson and his wife, Julie Kennedy-Thompson, acquired the acre lot last year on Hidden Valley Drive south of Cave Creek Road.

In exchange with the Thompsons, the town paid Arizona Public Service Co. to relocate a power line, removing a 20-foot easement that cut the property in half, Marlow said.

Calls to the Thompsons were not immediately returned.

The tank is scheduled to be in operation by May 1, Marlow said.

The lot surrounding the water tank will be used as a storage yard for the public works and utilities departments, replacing a town-leased site near the Cave Creek American Legion, Marlow said.

The Thompsons also own adjoining property.

The Cave Creek Town Council will consider the land acquisition at a special meeting 7 p.m. Monday. The Maricopa County Assessor's Office lists the full cash value of the property at about $1 million for the 2009 tax year. For the 2008 tax year the value was $560,000.