Cluster Development
What is it?
Cluster development groups new structures and built infrastructure closer together, concentrated on a portion of a property, away from important natural infrastructure. The remaining portion of the property that contains important natural features is then protected from development. Cluster development can extend beyond a specific subdivision, and coordinate to connect open space from one development to the next. Cluster development is most applicable in areas where there is a significant portion of undeveloped land, and where land parcels are large.
How can municipalities use it?
Municipalities can use cluster development to protect and connect natural infrastructure by reducing the footprint of development. In exchange for clustering homes on a smaller portion of land, municipalities can relax other requirements for developers, such as minimum lot sizes and setbacks. Municipalities can also incentivize developers to cluster using (e.g.,) density bonus programming (increased density in exchange for developing a smaller footprint).
The remaining portion of land after cluster development is complete can then be subdivided and designated as park or natural area, or become subject to a conservation easement. Cluster development is most effective when the municipality has mapped its important natural infrastructure, and can strategically connect natural infrastructure across multiple subdivision projects.
What are the advantages?
Cluster Development offers several advantages, including:
Ability to protect and connect natural infrastructure
Reduced environmental impacts in comparison to conventional development
Lower infrastructure costs to developers
Lower servicing costs to the municipality
Social and recreational benefits of open space amenities
What should you watch out for?
No tool is a silver bullet. There are issues for municipalities to watch out for with Cluster Development, including:
Regulations, such as minimum lot sizes and setbacks, may prevent the ability to cluster develop if not coordinated
On its own, clustered development may promote sprawl unless used in coordination with other policies such as growth boundaries or conservation easements which protect the undeveloped land
Community perceptions may favor the larger lot sizes and lower densities of traditional development, so education may be needed to encourage understanding of the benefits
If septic systems are currently being used on the land, cluster development may require connection to the municipal sewer system as septic systems require larger lot sizes
How can it help maintain natural infrastructure?
Cluster development can be used to reduce the overall development footprint on a given parcel, thus reducing the impact to the existing natural infrastructure system. This helps to protect natural infrastructure assets (e.g., wetlands) from development, ensures the natural infrastructure can function (e.g., stormwater storage), which in turn allows benefits to be maintained (i.e., flood and drought mitigation).
Resources
Greener Prospects – Randall Arendt is a leading expert on cluster development. His consulting firm, Greener Prospects, works to bridge the gap between land-use planning and land conservation.
Managing Change in Rural Manitoba: A Manual for Conservation Subdivision Design – Authored by Randall Arendt, this manual explains in a straightforward way how to design rural subdivisions that protect open space, woodlands, natural areas, wildlife habitats, and wetlands.
Chester County Planning Commission, Municipal Toolbox – Additional information and case studies on cluster development prepared by Chester County Planning Commission in Pennsylvania.
City of Colwood, British Columbia – The City of Colwood council approved comprehensive development zoning that provided amenity density bonus and the clustering of development away from an important bird sanctuary site by merging six lots and subdividing the site into parkland and the development site.
West Caln Township, Pennsylvania – West Caln Township in Pennsylvania has included cluster development standards in their zoning ordinance since 2005.
Green Bylaws Toolkit: for conserving sensitive ecosystems and green infrastructure – This document is an important resource for understanding how municipalities can safeguard the environment, from a regional to a site level. It clearly explains each tool, and provides case studies and examples of bylaws that are in use in British Columbia. This document describes the use, and provides a case study of, Cluster Development.
Protecting Riparian Areas: Creative Approaches to Subdivision Development in the Bow River Basin. A Guide for Municipalities, Developers and Landowners – Designed to assist municipalities and those thinking of subdividing rural land, within the Bow River Basin. This document includes a section on clustering of development.
Growing Water Smart: The water-land use nexus - This document provides information on compact development for the benefit of water conservation.
Did we miss something?
If you know of a resource that should be on this list - or your municipality has a sample or case that should be here, please let us know!