Conservation Subdivision Design
As one of the many tools a community may use to create a green infrastructure network, conservation subdivision design is one of the most widely utilized. Conservation subdivision design is the concept of allowing development of buildings closer together on a smaller portion of land so that components of green infrastructure may be preserved as part of the amenity for the development. A conventional subdivision usually divides all of the available land into lots based upon the minimum lot size established by a zoning ordinance.
In contrast, conservation subdivision models typically divorce the concepts of density and lot size. The overall density of a project may be determined by the gross acreage divided by the minimum lot size, but the actual dimensional requirements of each lot may be reduced to allow a more flexible placement of buildings. Open space resulting from conservation or clustering is typically more contiguous and protected by a conservation easement preventing development in the future.
RATIONALE
Many communities allow both traditional and conservation subdivisions. The clustering element of conservation subdivisions not only protects open space and environmentally sensitive areas. Conservation s but also requires less investment in infrastructure, as there is less distance among lots to cover. The open space and environmentally sensitive areas preserved in conservation subdivisions can be incorporated into a community’s green infrastructure network.
EFFORT REQUIRED
Numerous model ordinances for conservation subdivision design have been developed, and many publications and resources describe the pros and cons of conservation subdivisions. A conservation subdivision ordinance should be reviewed by local land use and zoning professionals and by legal counsel before adoption by a local government.
BENEFITS
Conservation subdivisions allow for land development within a smaller area, thus preserving a greater amount of open space. This model of development can reduce the impacts of sprawl, preserve open land for agricultural or recreational use, and protect environmentally sensitive resources. Open space areas can provide buffers and transitional zones between residential and agricultural land uses.
RISKS
Conservation Subdivisions are not a solution to sprawl. A risk occurs if a community utilizes this as its only approach to combat sprawl. Additionally, the ownership of open space areas will need to be addressed by local ordinances to ensure they are maintained and preserved. Typically, open space areas are held and managed by homeowners’ associations, but local governments and nonprofit land trusts are good options as well. When open space within a conservation subdivision is used for active agricultural operations, there can be some conflict between residents and the odors, dust and noise generated by traditional agriculture, so steps should be taken to minimize the conflict between uses.
ACTION AGENT(S)
Local government officials, citizens and community stakeholders, members of the development community, land planners, landscape architects, engineers and other private consultants, nonprofit land trusts
COSTS
Specific costs for the development of conservation subdivisions will vary based on the size of the project and local development restrictions. The development of conservation subdivisions typically results in cost savings over conventional subdivisions due to the reduced amount of infrastructure (roads, water and sewer lines, utilities). Cost of implementation of a conservation subdivision ordinance depends upon the amount of stakeholder input desired.
Any party with an interest in an initiative.The system of land, natural resources, and natural habitats that collectively comprise a community's underlying ecosystem. Green Infrastructure is present in every city, although its size, diversity, and strength vary greatly. Importantly, green infrastructure can be used to help offset negative environmental impacts, for example stormwater runoff and urban heat island effect.
