Large Lot Zoning
Large lot zoning establishes a large minimum lot size requirement to limit development densities in districts where the preservation of rural character, agriculture, forestry or environmentally sensitive areas is a goal. While in Vermont these minimum lot sizes are generally 25 acres, in other parts of the country lot sizes are 80+ acres in these districts. Several concerns including increased land consumption, leap-frogging development, increased infrastructure needs and the potential for rural sprawl have all been raised and should be considered by a community when thinking about implementing this tool.
Many communities in Vermont struggle with ways to keep large tracts of land open for farming and forestry, protect key natural habitats and water quality and maintain their rural character. Some towns have rural districts with 2-10 acre minimum lot size requirements and believe that they have “large lot zoning” and are accomplishing their town’s desire to maintain rural lands. However, in general, these lot sizes do not provide a land base large enough for sustainable, economically viable farming or forestry, nor do they support resource protection. Further, the close proximity to homes can increase tensions and conflicts between these uses.
Large lot zoning sets a minimum lot size with one residence, generally 1-2 acres, per lot allowed. Lot sizes for this tool vary widely. In Vermont, large lot zoning is primarily 25 acres and corresponds with the state’s current use tax abatement program. In many other states, lot sizes are much larger (40-160 acres). For example, some Oregon counties have an 80-acre minimum, others in Illinois are 40 acres and other in Pennsylvania are 50 acres.
The purpose of this technique is to lower the overall population density and protect environmentally sensitive areas as well as maintain larger tracts of land for resource uses, but allow some development and flexibility. From an administrative perspective, this is an easy tool to administer. From the standpoint of water quality protection, large lot zoning has been used to reduce the amount of impervious cover* and therefore the amount of stormwater runoff from a parcel of land.
Several concerns have been raised with this tool. If lot sizes are too small, natural resource protection will not be accomplished and it will make farming or forestry impractical and/or not economically feasible. Small minimum lot sizes can increase land consumption, cause leapfrog development and spread development over large areas which can increase the expense of providing infrastructure (roads, sewer and water) and services (fire and police protection, school transportation) to these areas.
Success in implementing this tool can be increased if a community considers layering tools, rather than relying on only large lot zoning. A study of agricultural protection programs in Lancaster County, Pennsylvania illustrate how overlapping techniques can result in a successful program.
Working closely with the farming community, this program combines zoning, growth boundaries, financial incentives and permanent land conservation. The towns in the county have large lot zoning of 25-50 acres that allow for one dwelling unit, but also allow by conditional approval farm stands, farm housing, bed and breakfast operations and other agritourism activities. They have regulations that protect farmers from nuisance suits, voluntary purchase of development rights and transfer of development rights programs. Their Urban Growth Boundaries promote compact development and limit the extension of sewer and water lines into farming areas. Together, these tools have resulted in a successful program in an area with severe development pressures.
If your municipality is considering implementing this tool in your town, make sure the lot size is large enough to accomplish your goals and considering other tools you may, or may not, already have in your toolbox that can complement and support large lot zoning.
*Impervious cover: is any land use alteration which causes water to flow over a surface instead of soaking into the ground. This includes roads, sidewalks, driveways, parking lots, swimming pools, and buildings, etc.
Related Case Studies
St. Lucie County, Florida. 2010. St. Lucie County Western Land Study. Options and Opportunities for the Future. This report provides both economic development and land use planning tools to consider for preserving a functioning network of agricultural, open space, and natural areas.
Vermont Land Use Planning Implementation Manual: Open Space Regulations. This provides more information on large lot zoning and other resource protection regulations.