Question 5 of 10: Greyfield Redevelopment of Declining Shopping Centres

Question 5: Greyfield Redevelopment of Declining Shopping Centres (10 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

The concept. A greyfield is a previously developed, economically obsolescent site whose existing improvements are worth less than the land beneath them, and which is not contaminated to the degree that would make it a brownfield. The archetype is the enclosed shopping centre or strip plaza built between about 1960 and 1985 on an arterial road at the then-edge of the city, now surrounded by mature neighbourhoods and out-competed by newer regional centres and by online retail. The name comes from the physical signature: hectares of grey asphalt parking, typically 60 to 70 per cent of the site, wrapped around a single-storey building with a blank exterior and no relationship to any street. Greyfield redevelopment converts that site into a compact, mixed-use, walkable district — a new public street grid subdividing the superblock, mid-rise and high-rise residential over ground-floor retail, structured or underground parking replacing the surface field, and public open space where none existed. It sits between greenfield development (undeveloped land at the periphery) and brownfield development (former industrial land requiring remediation), and it has become the principal supply of intensification capacity in built-up Canadian suburbs. Oakridge Centre and the Brentwood and Lougheed centres in Metro Vancouver, the Shops at Don Mills, Cloverdale Mall and Galleria in Toronto, and comparable projects in Calgary and Ottawa are the Canadian exemplars.

Benefits. The first is infrastructural: the site is already inside the serviced area, on an arterial, usually on a transit route and often at or near a rapid-transit station, so intensification here uses capacity that has already been paid for instead of extending pipes and roads into farmland. The second is the quality of the planning opportunity: greyfields are large — commonly 8 to 30 hectares — and, unusually, in single ownership, so a comprehensive master plan with a coherent street network, a real park and a phasing strategy is actually possible, which is almost never true of infill assembled parcel by parcel. Third, the fiscal return to the municipality is dramatic, since assessment per hectare on a mixed-use redevelopment is typically an order of magnitude above that of a single-storey retail box on surface parking, and the servicing cost is largely incremental rather than new. Fourth, it delivers housing supply, including rental and smaller units, inside established neighbourhoods where new supply is otherwise almost impossible, and it does so without displacing existing residents, since the land holds no housing to begin with — which materially lowers the equity objection that other intensification faces. Fifth, it improves the surrounding neighbourhood: an aging mall is replaced with the walkable centre those neighbourhoods never had, with daily shopping, services, public space and transit within walking distance for the existing residents around it. Sixth, the environmental gain is real: impervious area falls, stormwater is managed to a modern standard where previously it ran untreated off a parking field, urban heat island is reduced by tree planting, and district energy becomes feasible at the scale involved. Seventh, contamination risk is generally modest — a former gas bar, dry cleaner or underground tank — and manageable compared with a true industrial brownfield.

Challenges. The obstacles are as characteristic as the benefits. Legally, the mall itself is the problem: reciprocal operating agreements, anchor-tenant leases with covenants specifying parking ratios and prohibiting construction on the parking field, and long remaining lease terms can freeze a site for a decade regardless of what the plan says. Financially, redevelopment must be phased while the existing retail keeps trading to service the debt, so the sequence of demolition, parking relocation and construction is a constraint on design rather than a consequence of it, and the capital cost of structured parking, which is several times the cost of surface parking per stall, is carried early. In planning terms the site is almost always designated and zoned for single-purpose commercial with a low permitted floor space index and high parking minimums, so an Official Plan amendment, a rezoning and often a secondary or station-area plan are required, with the associated timeline and appeal risk. Politically, the surrounding low-rise neighbourhoods raise the full set of intensification objections — traffic, shadow, overlook, parking spillover, school capacity, and neighbourhood character — and they are well organised, so a serious and early engagement programme with credible transition and design is not optional. Technically, local infrastructure often needs upgrading even where regional capacity exists: sanitary trunk capacity, water pressure for tall buildings, stormwater retrofit to current standards, and intersection improvements on an arterial that is already congested. There is a parkland problem, since built-up areas have little land available and cash-in-lieu buys nothing nearby, so the park must come out of the site. And the surrounding street network is hostile — wide arterials, long blocks, missing sidewalks and no crossings — so the walkability created inside the site does not extend beyond it unless the municipality invests outside the property. Finally there is market and absorption risk: a large multi-phase project must sell or lease thousands of units through at least one economic cycle, and the negotiation of development charges, community amenity contributions and affordable-housing requirements determines whether it proceeds at all.