FLASHBACK TO 2006 / DESIGNING COMMUNITIES DIFFERENTLY IN CALGARY, ALBERTA: “Meeting the City’s expectations for rainwater management drove the merger of two innovative concepts in laying out new communities – Water Balance and Fused Grid. Saddlestone was to be the litmus test of their validity and effectiveness,” stated Fanis Grammenos, the innovator who pioneered the Fused Grid Model for compact community design and beneficial uses
Note to Reader:
The Fused Grid planning model was developed by Fanis Grammenos, formerly a senior researcher with the Canada Mortgage and Housing Corporation (CMHC) in Ottawa, and a team of colleagues. It combined two traditional street designs: the conventional loop and cul-de-sac pattern of the modern suburb and the grid pattern from the early 1900s. Fanis Grammenos is the co-author of Remaking the City Street Grid – A Model for Urban and Suburban Development.
Fanis Grammenos is the founder of Urban Pattern Associates, a planning consultancy and research firm. He is a regular columnist for the Canadian Homebuilder magazine, a contributor to books and to planning journals, periodicals and web sites.
G.R. Lovegrove is a professor of civil engineering and a research lead at the Sustainable Transport Safety (STS) Research Laboratory, at UBC’s School of Engineering in Kelowna, Canada. He is an author, contributor and expert consultant on sustainability texts used today by governments and universities across the globe.
In the article below, Fanis Grammenos looks back and reflects on what was accomplished in the City of Calgary when the developers of the Saddlestone community embraced the Fused Grid concept for community design.
Common ground, play space and community builder, also functions as a rainwater retention facility by incorporating Rain Garden technology.
A Balancing Triumph: How the Fusion of Two Models Created an Exemplar Community
“Planning, common experience shows, is an act of balancing competing interests, perspectives and priorities. And since interests often waver and priorities shift, the challenge of achieving a balance is forever new. And so it was for a 164-acre development in NE Calgary launched in 2006 – and it was met decisively,” wrote Fanis Grammenos.
The Water Management Challenge
“At the time (2006), entirely new priorities, along with old ones, were being staked at every corner of the planning universe. City planners, traffic engineers, environmental advocates, community leaders, interest groups, future residents and, importantly, developers plied their own imperatives, singular among them rain water management. A tangled web of interacting variables emerged from these demands; a truly formidable, complex puzzle: How to lay out a large subdivision that optimizes outcomes for each proponent’s priorities.”
“Enter the Water Balance and the Fused Grid models that appeared concurrently at the project’s early design phase. For Water Balance, “…the breakthrough in thinking came when the concept of a Rainfall Spectrum [emerged] to categorize the rainfall-days that occur each year.” This exacting attention to natural patterns was also a core innovation of the Fused Grid model.”
“Natural flow/growth patterns (catch basins, leaf veins, tree branches etc.) follow universal, definable rules, which long begged to be recognized in neighborhood layouts. When these two firsts were combined, a paradigmatic solution emerged.”
To Learn More:
Figure 1. The Fused Grid superblock enables a balance of competing needs for land use functions including the critical facility of stormwater retention (seen partially in the foreground)
Where and How Integration Happens
“The fused grid model rests on a replicable (but not repetitive) 16 ha (40-acre) superblock, a cellular unit (Figures 2 and 3), which displaces simplistic geometry for organic order. It follows the law of sizes, a law easily noticeable in a tree’s branching pattern: the further away from the main trunk, the shorter and thinner the branches are – a size hierarchy , ever present in organisms and complex systems in general.”
“Translated into a neighborhood street pattern, this means shorter, skinnier, end-of-line local streets. This basic rule has measurable, positive implications. Simple math shows that the closer this organic geometry is followed the more land becomes available for beneficial uses. Consequently, apportioning land among optional uses can be based on goals rather than strict geometry.”
To Learn More:
Figure 2. The transformation of a conventional, mechanistic street pattern to an organic one and the resulting land use advantage. (The higher levels of this network model can be seen here.)
Goals and Means
“By the project’s start, the City already had a firm set of priorities: rainwater retention, high connectivity and infrastructure efficiency. Along also came the pursuit of residential density, active mode mobility, traffic safety, and public transit serviceability. The developer, in turn, aimed at low upfront costs, increased lot and unit counts and creating an appealing, convivial milieu that would speed up sales.”
“Rainwater retention in Saddlestone is achieved by passive and active means: a) by reducing the road length and width to a practical minimum, the site’s available permeable surface increases b) by combining the central open space’s core function as a community recreational space with a Rain Garden system. Road length reduction also meets the City’s priority of curbing long term infrastructure costs and the risks of flood-water damage. It also reduces the developer’s upfront costs.”
“Satisfying the City’s quest for sufficient on-site water retention and the associated infrastructure cost reduction were only two of many positive outcomes from the merger of the two models. Opportunities were also created to meet other essential development goals such as:
- Facilitate walking and suppress driving by prioritizing foot connectivity.
- Improve road safety by reducing traffic volume and speed on local streets.
- Raise population density to make transit and other services viable.
- Offer a range of housing types to match the city’s changing demographics.”
“Table 1 shows that the Fused Grid plan exceeds the city’s connectivity average for both modes and it also the City’s targets, while reducing measurably the ROW area. This can be attributed to its inherent, systematic use of paths as a natural alternative to roads. A modeling study predicts substantial increase in walking.”
“Saddlestone has met and surpassed population density aspirations to achieve a veritable “urban” profile. It has about 2.5 times the density of two subdivisions, one typical and the other intentionally atypical (New Urban).”
“Table 2 compares their population, unit and occupancy densities. The density increase achievement can be partially attributed to the presence of the generous central open space, which, research shows, can compensate for the compactness of development – a fair trade between small distributed open spaces and a generous common one. Another method to achieving higher density is through the inclusion of a variety of unit types and pricing levels reflecting the city’s current household demographics.”
“Figure 3 below compares the distribution of housing types and shows how Saddlestone leans toward serving smaller households with affordable options by the inclusion of a higher share of apartments and two-generation houses than elsewhere in the city.”
Echoes of Approbation
“During Saddlestone’s 10-year development, in a parallel, independent initiative, Barcelona applied the superblock model to its existing urban grid with identical objectives: increase site permeability, provide public green space, exclude through traffic and reduce its impacts on air quality.”
“Barcelona’s bold initiative, working within an existing built environment rather than a blank slate, has now become an international beacon of the superblock concept.”
“Figure 4, a reconstructed superblock (16ha) using Barcelona’s own build form, explains the City’s method of application. This reconstruction implies that while a street pattern is immutable, build form framing it can vary over time from single family homes to compact 6 to 8 story apartments – there is no causal link.”
“Meeting the City’s expectations for rainwater management drove the merger of two innovative concepts in laying out new communities – Water Balance and Fused Grid. Saddlestone was to be the litmus test of their validity and effectiveness.”
“The outcomes no only validated their joined positive impact but also surpassed City goals and expectations, as the comparative statistics show ten years into the development’s growth. A successful prototype was created worth replicating in other regions and districts aspiring to meet the environmental and housing affordability challenges,” concluded Fanis Grammenos.
Figure 4. Barcelona’s application of the Superblock concept reinterpreted with a modified image (Google Earth)