Open space refers to land that is either undeveloped or not intensely developed for residential, commercial, industrial or institutional uses. In addition to natural beauty, open space can provide important recreational, environmental and cultural benefits to communities. Westchester County's Planning Department inventoried and mapped open space in 2006 and developed an updated interactive map in 2022. The latter is part of an ongoing initiative to develop an updated inventory of open spaces, increase public awareness of them, and improve access to those open to the public.

In 2022, the County inventoried about 760 square miles of permanently protected open space, up from 705 square miles in 2006. A little more than 1,000 square miles of land was not permanently protected but still contributed to open space character in 2022 (e.g., private recreation facilities, farms, land along utility lines). This was similar to the County's 2006 count. Water supply lands represented the single largest category, at nearly 350 square miles. County parks was the second largest, at nearly 300 square miles, followed by state parks, local parks, and private institutions.

The County recorded a net loss of about 60 square miles of farmland, stables or nurseries between 2006 and 2022. There also were decreases in private recreation sites and land for public institutions other than parks. The County gained permanently protected open space in state parks, nature preserves, and county and local parks. The County added a new category in 2022 for land held by homeowners' associations, which amounted to a little more than 75 square miles.

Homeowners Associations and Common Lands is a new category added in 2022. The data set is a work in progress and Westchester County continues to make updates based on feedback from local governments and land trusts. There are no immediate plans for when a comprehensive update might be conducted. For more information, visit https://planning.westchestergov.com/initiatives/open-space.