Why is the NCC letting these parkways go dark?

The National Capital Commission is embarking on a major project to replace hundreds of street lights lining the Rideau Canal in central Ottawa, but not before letting the majority of them go dark — and in some places, letting them stay that way for years.

Why is the NCC letting these parkways go dark?
Cars travel along a dark road beside a canal at night.

The National Capital Commission is embarking on a major project to replace hundreds of street lights lining the Rideau Canal in central Ottawa, but not before letting the majority of them go dark — and in some places, letting them stay that way for years.