Major work is defined as something that would require an environmental assessment to be conducted by law. That law is both garnered out of CEAA, the act, and under our particular act. If substantial interference or a potential for substantial interference to navigation is foreseen, that would garner an environmental assessment requirement, triggering CEAA.
In addition, if it's an unlawful work that is now coming back for formal approval, then that too would automatically generate an environmental assessment. So, in short, environmental assessment is required.