The new weir operation rules are working and we have realized the benefits of storing more water in the lake when we were again in the midst of our annual summer drought.
Last year at the end of July, we were being forced to dump water out of the lake to comply with the old operating rules. This was done despite the objections of many of our community leaders, Cowichan Tribes and the Cowichan Watershed Board. The resulting low river flow crisis of last fall caused a public outcry about mismanagement of our water resources that has led to the revision of the operating rules to allow for slightly more water to be stored in the lake this year and into the future.
This year the lake level on July 31 was about where it was last year despite the fact that we had no significant precipitation for over a month. This is because we have not been forced to dump water unnecessarily to comply with the old rules. Under the new rules we were allowed to keep all the water we had, up to the top of the weir, until July 31st instead of July 9th as was the case in the past. We have been able to maintain the flow in the river at the minimum required rate and keep as much water as possible behind the weir. Our current lake level is below the top of the weir and below the maximum levels allowed by the new operating rules, which means that not only did we not have to release the water we had stored but we were able to keep any water we might have gotten had there been a rare summer rain.
Rodger Hunter of the Cowichan Watershed Board estimates that we have about 9 days of river flow stored above the levels that would have been required by the old rules. This volume of water will very likely be of tremendous benefit later in the summer and early fall.
It should be pointed out that these increased summer storage levels are still well below the average winter water levels. The average winter high water mark is 1.4 meters above the top of the weir, so by storing water to the top of the weir we are not putting water anywhere is has not been earlier in the year in significant quantity.
Records were being set all over our province by the month of July 2013. Kamloops and Revelstoke both had the driest month ever recorded. Vancouver had never had a drier or sunnier month with their total rainfall for July at essentially zero. That has never happened in any month in Vancouver since records have been kept. We have no official weather monitoring station in the Cowichan Valley but there is no reason to believe that we have had the driest month ever as well.
Climate change is a reality and we must make plans to adjust to the changing conditions, which in our community will appear as increasing summer drought periods. It is clear that increased summer storage in our lake is going to be key to preserving the health and viability of our watershed and our community. By increasing our summer storage capacity we will be able to enjoy the benefits of beautiful summer weather without worrying about our river running dry in the fall.