Cluster Development in Plain English
What is Cluster Development?
Cluster development is a development arrangement in which all buildings allowable on a site are concentrated on a portion of the site, leaving the remainder of the site undeveloped. This contrasts with the conventional land development and subdivision approach, which is to divide an entire site into lots, each of which meets minimum zoning lot size requirements and may be used for building construction. By clustering buildings together on smaller lots rather than spreading development throughout the site, a developer has greater flexibility to design around environmental and other constraints, without having to reduce the total number of developable lots. As a result, cluster development can provide a win-win approach for communities and developers to protect and buffer environmentally sensitive areas, to preserve important site features, or to provide recreation areas or natural open space. It also provides the flexibility to conserve or buffer natural resource lands, such as farmlands. Maintaining the undeveloped lands in productive uses, such as orchards or pastures, can contribute economic value to the project. Cluster provisions in rural areas tend to focus more on securing expanses of open space consistent with rural character, or protecting environmentally sensitive areas and natural resource lands. In urban areas, cluster development's greatest value may be to provide site design flexibility, although it may also provide for recreation, open space and resource protection. The open space tracts in cluster developments are generally permanently preserved. Clustering also can reduce infrastructure costs for developers and communities since the length of roads and utility lines are reduced. Cluster development generally refers to residential developments, although they are sometimes defined to include commercial or industrial development.
Cluster Development as Applied in Washington
The Growth Management Act (GMA) encourages innovative land use management techniques including cluster development (RCW 36.70A.090). Some Washington communities are finding that cluster development is a useful tool for accomplishing many GMA goals, including protection of environmentally sensitive areas (critical areas) conservation of productive forest and agricultural lands, retention of open space, and reduction of sprawl (RCW 36.70A.020). Cluster developments also can offer varied and affordable housing types. However, growth management hearings boards have cautioned that clustered development in rural areas must remain compact and rural in character.
In general, clustered development is a voluntary option for developers in Washington communities, although a few communities have adopted mandatory cluster requirements to protect sensitive areas.