Strictly from an Environmental Perspective....
Overall the least amount of environmental concern is associated with a rehabilitated 3 lane Lions Gate Bridge and an improved / widened 3 lane causeway through Stanley Park. The environmental concerns associated with modifying the existing bridge to four lanes, with a four lane surface road on the existing centre-line of the causeway, are only slightly greater.

Strictly from an Environmental Perspective....
A tunnel or new bridge approach on the North Shore should be located as close to the existing bridge as possible.

Strictly from an Environmental Perspective....
If a bored tunnel crossing of Stanley Park is utilized and part or all of the existing causeway is reclaimed, some impacts (which can be partially mitigated) may be acceptable to Lost Lagoon to create a portal entrance for a bored tunnel..

Strictly from an Environmental Perspective....
The depressed road and cut and cover crossings of the Park pose far greater environmental problems than a surface route along the existing existing causeway or a bored (mined) tunnel.

The environmentally preferred crossings of Stanley Park are via a bored (mined) tunnel if a new route through Stanley Park is required - OR - a surface or bored (mined) tunnel along the existing causeway right-of-way.

Strictly from an Environmental Perspective....
The First Narrows immersed tube / cut and cover tunnel options pose significant archaeological, noise, socio-economic, aquatic and wildlife concerns. These options should not be studied further.

Strictly from an Environmental Perspective....
The Brockton options pose significant noise, socio-economic and aquatic concerns. These options should not be studied further.

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