There are over 10,000 dams in Canada owned by the federal and provincial governments, electric utilities, industrial and mining companies, irrigation districts, municipalities, and private individuals. Hydroelectric generation is significant with Canada generating some 350 TWh/year which represents about 60% of the national electricity production and close to 10% of the global output of hydro power. Other dams include those for irrigation (mostly west-central) and water supplies. Similar to the United States, many of Canada’s dams are nearing the end of their intended lifespan and decisions will have to be made to renew or remove. Dam removal and river restoration is widely considered a preferred outcome, but such discussion and decision-making is still in its infancy and still complicated by conflicting interests of green energy, climate change, water use, First Nations interests, and politically-motivated infrastructure decision making.
The specific challenges of three recently considered dam removals in New Brunswick, Canada, are presented as representative of the challenges faced for dam removals of differing scales. First, a small-scale dam and causeway (the Eel River Dam) intended as a water supply for local industry faced a lengthy regulatory process and considerable opposition from industry despite strong First Nation support and little public opposition. Second, a medium-scale dam and causeway (the Petitcodiac Dam) faced challenges associated with residential developments and recreational opportunities along the reservoir despite strong First Nation and other public support and a regulatory mandate for restored fish passage and addressing climate change risks in this dynamic estuary. Third, a large-scale hydro facility (the Mactaquac Generating Station) faced many of the issues of the small and medium dam removal projects plus challenges unique to large-scale hydro-generation such as public and political favour of “green” energy, a nearly 100 km long headpond with residential and recreational activities, and a potentially much greater extent and magnitude of ecosystem effects. While the outcomes of these three examples differ, there was similarity among them that reflect the challenges for dam removal in Canada.