In 1980 I worked for Marine Pipe doing a series of loops on the then Trans Mountain now Kinder Morgan line through the Coquihalla river basin. I can't remember the exact amount of river crossings but it was in the low to mid teens. The pipeline follows the entire length of the river from the lake to the Fraser. When they twin it the same route will be followed they can't avoid it.
When you do a river crossing it involves excavators digging a 2-3 meter deep trench up to 15 meter wide depending on the amount of sluff you have across the river dragging a huge piece of 24" pipe weighted down with big concrete clamp on weights into the trench then burying it with the gravel you bailed out.
It doesn't matter at all whether or not you are in fish habitat, fish bearing water, active spawning beds or whatever, that is the route the pipeline takes and that is the route and the methods they'll use when they twin it. The timing of the work is not done to minimize the impact on the fish, it is done when the water levels are at their lowest to minimize the expense of the work.
This is the way it's done, this is the way it'll be done again when they twin the Kinder Morgan line, there is nobody out there to look out for the fish, get used to it, that pipeline will be rammed down our throats or up where ever whether we like it or not.