Even 15 years later, few things get Torontonians’ blood boiling like talk of the city’s amalgamation. The shotgun marriage imposed by the province brought together the six boroughs and the upper-tier government that were formerly part of Metropolitan Toronto into one “megacity.”

There are still those who call for de-amalgamation. The city, they argue, would function much better if we returned to the pre-merger borders. Others blame amalgamation for a cultural divide within the city. Reporter Robyn Doolittle is perhaps the latest to outline this case in her new book Crazy Town: The Rob Ford Story, where she describes the theory that amalgamation caused an urban-suburban divide that eventually gave rise to Ford Nation and Toronto’s current governance malaise.

The critics are right: amalgamation does still haunt us to this day, but not in the ways that many think. The biggest legacy is that Toronto’s amalgamation created a city that is both too big and too small — an outcome that has hamstrung our ability to tackle many of our most pressing civic challenges.

A new report by the Institute on Municipal Finance and Governance looks at the legacy of amalgamation in both Toronto and Montreal. In both cities, provincial governments pursued restructuring as a means of reducing the number of governments and politicians, and finding efficiencies and cost savings. While hugely unpopular, amalgamation stuck around in Toronto. In Montreal, local resentment led to de-amalgamation referenda that reversed the reforms in some former municipalities, and forced the creation of an upper-tier “agglomeration” government to co-ordinate the messy governance arrangement on the island.

We evaluated the legacies of both amalgamations based on four criteria: efficiencies and cost savings, service levels and tax burden, accountability and local responsiveness and regional co-ordination. There is little evidence of efficiencies and cost savings in either city. In Toronto, we found that expenditures on many of the lower-tier services that were merged, such as fire and garbage, actually increased after amalgamation. However, we did find that there was greater equity in the distribution of services and tax burden across Toronto, although this has not been the case in Montreal. Finally, local accountability has probably improved in Toronto while responsiveness has likely diminished.

Perhaps the most important legacy in both cities, however, is the failure of the amalgamations to tackle the need for planning and co-ordination across the broader metropolitan region. Then, as today, Toronto represents only about half of the population of the Greater Toronto and Hamilton Area, with its borders and service responsibilities overlapping with the surrounding large, fast-growing suburban municipalities.

In short, Toronto’s amalgamation created a city that is both too big and (mostly) too small. The city is too big to feel close to citizens and provide adequate access points for input. On the other hand, the city is too small to tackle big regional issues. The upcoming municipal election campaign, for instance, will focus heavily on transit, infrastructure, economic development and growth planning — all of which need to be co-ordinated across the metropolitan area.

Of course, the problems posed by being part a large metropolitan region are not just Toronto’s. This is a critical issue for the provincial government and for other municipalities in the GTHA. Today, much discussion is focused on how to move people around the region. Whether we are debating subways, LRT, the Gardiner Expressway, rail links to Pearson airport or expansion at Billy Bishop airport, what is clear is that these are regional projects and require regional support.

Other cities have tackled this institutional deficit. In Montreal they created the Communauté Metropolitaine de Montréal, a regional body that serves 82 municipalities in and around the city and has broad jurisdiction for co-ordinating a range of economic, social, environmental and transportation services. In the U.K., London is part of the Greater London Authority, which has a similar mandate for strategic regional planning, policing, economic development and transit, with an elected mayor and assembly.

Toronto is part of regional institutions, but they are certainly not as comprehensive as those mentioned above. Metrolinx, a provincial agency, was created to co-ordinate transportation planning across the region. But clearly, given the linkages between transport and land use, economic development and a range of other issues, more comprehensive regional governance arrangements are needed.

Simply put, solving some of Toronto’s most pressing challenges will require bridging this governance gap with the broader metropolitan region. As the election campaign heats up, it is this legacy of amalgamation that should be keeping leadership hopefuls up at night.

Enid Slack and Zachary Spicer are with the Institute on Municipal Finance and Governance, a cities research centre at the University of Toronto’s Munk School of Global Affairs.