Preliminary plans to develop one of Orono’s biggest remaining parcels of open land were approved Monday.

The City Council voted for preliminary plat approval to build 11 houses on a 93-acre estate that Doug Dayton, the grandson of Dayton’s department store founder George D. Dayton, bought 50 years ago. Doug Dayton, uncle of Gov. Mark Dayton, also was the company executive credited with launching Target.

When he died in 2013, his widow, Wendy Dayton, vowed that the land wouldn’t be sold to developers, and plans were announced last year for an 83-acre conservation easement to preserve prairies and land that her husband had restored. About a year later, though, plans have changed, with a state tax law alteration having made the situation more complex.

Developer George Stickney’s Mooney Lake Preserve calls for leaving nearly 50 of the 90 acres undeveloped and most of the rest of the land subdivided into 11 3-acre lots, some of which will have rules to protect wetlands and trees.

In June, the city’s Planning Commission recommended approval, and the City Council agreed July 13 in a 4-1 vote to draft a resolution for preliminary plat approval, which drew unanimous approval Monday.

Now, the city says the plans need approval from Hennepin County and the Minnehaha Creek Watershed District as well as final approval from the Orono City Council, expected at the end of August or in early September. If the plans are OK’d, construction could start this fall.