WCEL > Issues > Urban Growth and Development > Smart Bylaws Guide > Part 2 > Green Infrastructure Shaping the Block

Smart Bylaws Guide – Green Infrastructure Shaping the Block

Rather than paving over the ecological processes and environmentally significant areas in urban places, municipalities are creating development practices that incorporate the green infrastructure into new development.  This includes tailoring the shape of blocks and subdivisions to allow the green infrastructure, particularly watercourses and trees, to manage rainwater and provide a host of ecosystem services.  New development respects, and in some cases enhances, natural processes.

A common example of this approach is creating lot lines that do not impede an existing watercourse and requiring building setbacks from the watercourses.  Many municipalities also prohibit the cutting of significant trees and require development to accommodate the urban forest.  A more engineered approach involves constructing rainwater detention ponds or greenways in new subdivisions that also act as neighbourhood amenities  (An example of the latter is the new Grandview Heights Neighbourhood Concept Plan in Surrey, which builds on the Fergus Creek Integrated Stormwater Management Plan to incorporate greenway corridors that will serve multiple functions - providing recreational trails, drainage and stormwater management, natural forest and landscaping, and important habitat and riparian protection.)  Development permit requirements can also help staff to tailor new developments to specific block and site conditions.

For example, the Willowbrook Subdivision at 650 MacKenzie in Saanich involved the alteration of a two hectare cow pasture, within the urban containment boundary and in a single family neighbourhood, to restore part of Swan Creek and allow housing to be built in what had been the 200 year floodplain.  In return for gaining approval for 39 single family dwellings, the developer paid for the relocation and restoration of the portion of Swan Creek, and the construction of a series of stormwater treatment ponds that ensured that the housing was no longer located within the 200 year floodplain.  Seventeen percent of the land was dedicated to Saanich as parkland, and the stormwater ponds were constructed in the new park and on a Saanich sanitary sewer right-of-way.  An interdisciplinary team worked with the developer, regulatory agencies, municipal staff and neighbours to obtain support for the project.

The District of Highlands, located northwest of Victoria and composed largely of large lot rural properties in their natural state, attempts to cluster development to minimize the impact of new roads and cleared land.  Incorporated in 1993, one third of the municipality is park land and the first goal of the Highlands OCP is to protect the integrity of the natural environment. Respecting the mapped environmentally sensitive areas and greenways in the municipality, Highlands staff and council attempt to cluster all levels of development. At a municipal scale, higher densities are limited to the south of the municipality in an area adjacent to the District of Langford that is designated for urban development. In neighbourhoods and on individual lots, development is clustered to preserve contiguous areas of greenspace and to avoid ecological disturbances.

Almost all of the rezoning and subsequent subdivision applications in the Highlands are addressed through spot or unique zones. Using spot zoning, the municipality custom designs each site primarily based on ecological features, and, for some developments, the amenities to be provided in exchange for increased density. Because the Highlands is a largely undeveloped area, a high degree of flexibility is possible in site and building design. In some cases, it is possible to include a riparian area or natural area buffer within a new park rather than manage these within a developed area. When an area is very ecologically sensitive, development proposed on that particular part of the property will be relocated before an attempt is made to mitigate its impacts.

An example of a greenspace-protecting development in the Highlands is that of the 190 hectare Western Forest Products property at Scafe Hill. The land had been zoned, since 1982, as Greenbelt Two that permitted subdivision into 15 lots of no less than 12 hectares. The rezoning application was initiated during the development of the regional Green/Blue spaces strategy that identified a three kilometre greenway linking Mount Work Regional Park to Thetis Lake, Francis-King and Mill Hill Regional Parks. Most of the property contained important wetlands, watercourses, second growth forests, rocky outcrops and areas of Arbutus and Garry Oak. Because of environmental sensitivity and the high cost of building roads to access 12 hectare lots in the Highlands, it made ecological and financial sense to cluster the development.

The result was a 26 lot neighbourhood, each lot averaging 1.5 hectares. Development costs were significantly reduced because less road was required to service the lots.  Each lot had a natural buffer around its perimeter and most are adjacent to park land.  Approximately 90% of the original property is left in a natural state. The project added 145 hectares to Thetis Lake Regional Park as greenway. The municipality, landowners and The Land Conservancy, a provincial land trust organization, registered joint conservation covenants on these lots to protect the 75% of the lot areas comprising smaller habitats and features.

Resources

The Living Site and Infrastructure Challenge (Cascadia Green Building Council, November 2007, PDF)