Overlay Districts
In Brief
An overlay district is a common tool for establishing development restrictions, or extending development incentives, on land within a defined geographic area or characterized by specific physical features or site conditions. Adopted as part of a zoning bylaw, overlay districts are superimposed over one or more underlying conventional zoning districts in order to address areas of community interest that warrant special consideration such as historic preservation, or protection of a particular resource.
Summary
Vermont planning statutes (§4414(2)) specifically authorize municipalities to adopt overlay districts to “supplement or modify the zoning requirements otherwise applicable in underlying districts in order to provide supplementary provisions for areas such as shorelands and floodplains, aquifer and source protection areas, ridgelines and scenic features, highway intersection, bypass, and interchange areas, or other features described in section 4411 of this title.”
- Floodplains and riparian areas are often protected with overlay districts.
The most common application of overlay districts in Vermont are flood hazard districts, where certain types of land use and development are required to comply with site and building standards if the property is located within a mapped flood hazard area. Other common types of overlay districts include:
- Natural Resource – often utilized to protect hillside development, farmland, watershed protection and stream corridors.
- Historic Preservation – examples include historic district design standards.
- Design Review – utilized to ensure new development fits into the existing community character. Examples include highway corridors and central business districts.
- Public Safety – often associated with airport hazard zones, fire safety zones and geologic hazard zones.
- Development Incentives – examples include parking districts, that reduce parking requirements in compact, mixed use areas, or Transit Oriented Development (TOD) Overlay Districts that grant incentives for compact, mixed use development within walking distance of transit stops.
There are many possible uses of overlay districts to achieve smart growth policies. In Vermont, overlay districts have been used to ensure that buildings within a historic district is compatible with the historic character of the area, to protect farmland and scenic viewsheds, and to avoid impacts to ecologically sensitive areas.
Related Issues
Related Case Studies
Resources
Well Grounded: Using Local Land Use Authority to Achieve Smart Growth, by John R. Nolan.
Vermont Planning Statutes. This link provides the legal framework for overlay districts as referenced in the Vermont Planning Statutes
