Every week during the ‘control’ season when the weir spill gates and boat locks and is in use (closed or partly closed), Catalyst Paper Mill’s Environment Manager provides an update by email to anyone interested. Excerpt below re-posted with permission. The full update can be viewed at https://www.catalystpaper.com/page/cowichan-water-management-information
Weekly email update from Catalyst Paper, June 15, 2020:
Greetings on a wet summer day,
We have arrived to final day of 15 cms from lake and today will begin to ramp flow down to summer base flow of 7 cms.
In order to protect fish and fish habitat, flow reductions from 15 cms to 7 cms are conducted at 1 cms reduction per day.
Catalyst begins to reduce river flow from lake in afternoon and into early evening in order to have flow reductions in river occur under cover of darkness.
Water leaving the lake passes by Duncan about 12 hours later and the survival of small fish depends on them not being trapped in disconnecting side-channels and pools of water.
Weather forecast not showing much rainfall in coming week and snow pack shows almost fully melted.
With lake as full as it is, flow reductions to 7 cms could result in lake level rising to overfull.
Flow reductions could be stopped if risk lake level rises to or to above 100% level.
Brian Houle, Manager, Environment, Catalyst Crofton