Project Osmium is a Microsoft cloud – or perhaps more technically a cloud-computing data center – that is sure to be a rainmaker for the city of West Des Moines. The project will open 5,000 acres to development, could double the size of a rural school district and add millions in valuation to a county that is confronting a courthouse crisis.

West Des Moines Mayor Steve Gaer said during a news conference Friday that revealed details about Microsoft’s third data center project for the city that annual property tax revenues in his city alone will increase by $12 million a year.

The reason: Microsoft and the city have agreed to an annual valuation of $307 million a year for a project that will span 200 acres, add an estimated 1.7 million square feet of structures and generate a total investment of up to $2 billion when the project is completed in 2022.