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Nonconforming uses and structures have been with us every since zoning first emerged in the 1920s. Since that time, they have represented the "Achilles heel" of planning and zoning. The root of the problem is that nonconformities reduce the effectiveness of what a community is trying to accomplish through its comprehensive plan, as implemented by its local zoning regulations. The continued existence of nonconforming uses, for example, undermines what a community is seeking to achieve when it establishes specific allowable uses for a zoning district.
At the same time, communities -- quite understandably -- have been reluctant to call for the removal of ongoing businesses and existing structures, reflecting substantial financial investments, just because they fail to comply with current zoning requirements. The "solution" has been to subject nonconforming uses and structures to a diverse assortment of restrictions, all intended to hasten the day when the particular use or structure either "disappears" or comes into compliance with the existing zoning regulations.
Nonconformities come in all shapes and sizes. But what they represent is simple enough to state: non-compliance with the relevant requirements of a particular zoning district or classification. ...
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