Government owns 10 to 30 percent of the footprint of most cities, and the public sector is the nation's largest property owner. But property management is hardly a core function of government, so it's not surprising that many jurisdictions don't even have an accurate inventory of their own property. The data is often scattered across the various agencies in charge of different parcels.
Much public land is underutilized and expensive for taxpayers. The Office of Management and Budget estimates, for example, that it costs about $1.7 billion per year to maintain and secure underutilized federal properties. For municipal governments, there's also foregone property tax revenue and wasted opportunities to use the land to support local economic development.