As 2015 draws to a close we can look back on another eventful year in our community. We faced the third serious drought in the past four years, which was marked by the driest summer period ever recorded.
In January we started noticing a disturbing lack of snow in the mountains surrounding our lake. We had been getting normal amounts of precipitation but it was just not cold enough for snow to form in the mountains. This was an ominous sign for our summer as the record setting warm El Nino ocean current was persisting and this meant we could be facing a dry and warm summer.
By the end of March there was still no snow in the mountains and this was about the time we expect to see the peak of the snow pack. We could see the writing on the wall; there would be no melting snow to top up the lake this spring. By April 15 the weir was below full storage. The rule curve allows full storage in the weir until July 21 so we knew that without significant rainfall in May we were facing serious water shortages again this year. What followed was the driest May in the 61 years for which we have local records.
The lack of melt water entering the lake may have contributed to an algae bloom in the lake and river in June. Surface water temperatures were above normal in the lake and river for most of the summer creating good conditions for algae growth but marginal conditions for fish health.
The July 21 date for full weir storage was changed from previous years when July 1 was the last date allowed for full storage. This decision was appealed by a group of six lakeshore residents and after more than a year the Environmental Appeal Board released their decision upholding the July 21 date and rejecting the claims of the appellants. This decision made the key finding that there is no expropriation of lakeshore properties under 164 meters elevation, which is the average winter high water mark. The top of our weir is 162.37 metres.
Even though we knew we could be in trouble for water again this summer we provided 25 cubic metres per second (CMS) to the river in April to enable steelhead and salmon fry to safely emerge from the gravel and find safe habitat in the wetted areas around the river banks.
As May started we began to slowly reduce the river flow to 12 CMS and salmon fry rescue operations kicked into high gear as the Cowichan River and all the tributaries feeding the lake started dropping quickly. In the end we rescued well over 100,000 salmon fry by moving them from drying pools into the main stem of the river or the lake.
With the lake level continuing to drop in June, river flow was further reduced to 5.5 CMS, well below the desired seven cms, in order to conserve water for the expected dry summer.
At about this time, the Cowichan Lake and River Stewardship Society started year two of the three-year Shoreline Stewardship Program. Local students were hired and over the summer they restored 10 properties, five on the river and five on the lake. Invasive plants were removed and native riparian plants were planted in their place to re-create natural shoreline habitat.
As the summer started river flow was again reduced to 4.5 CMS and projections were that the river would start running dry about the end of September if we got no significant summer rains. Watering restrictions were put in place for most of our community. The CVRD, Cowichan Tribes and Catalyst began discussions on how we can increase our summer water storage by building a new weir and funds were applied for from the provincial government.
By the end of August we were only a couple of weeks from reaching zero storage and the prospect of a drying river. Faced with the probability of having to shut down their mill, Catalyst applied for the ability to pump water over the weir in the event of reaching zero storage. Seventy per cent of the water pumped would remain in the river and keep the fish in it alive while 30 per cent would be used by Catalyst to keep their mill running.
In the face of growing desperation we got the miracle we needed. On Aug. 28 the skies opened and life giving rains arrived unexpectedly. From May 1 until Aug. 27 we had received 51mm of rain. From Aug. 28 until Sept. 16 we got an additional 85 mm and the threat of zero storage was erased when still more rains came in September.
As September came to a close our river was again up to 25 CMS and rising, just in time for the fall run chinook salmon to enter the river and access their spawning grounds in the upper river and lake tributaries. There would be no salmon trucking necessary this year and the river was in great condition to welcome the returning chum and coho salmon as they arrived in October and November.
Our Chinook salmon run was just about as expected this year but the chum salmon were below expectations and the coho salmon returns for all island rivers were way below normal. It is estimated that coho returns were only about 10 per cent of expectations so this species may have been adversely affected by the unusually warm “Blob” of water in the north Pacific this year.
We learned again this year how critically important it is for our community to increase our summer water storage capacity. I understand there is some frustration in our community over rising taxes but I believe most of us can see the urgency of securing our summer water supply. This is one project that cannot be considered optional and it is very likely that the provincial and federal governments will contribute most of the funding.
Securing and controlling our access to safe, clean water will pay back huge benefits in the future. With more summer water available we will have a healthy river and lake, the potential for growing much more local food and increased industrial capacity. Just imagine, we might have the option to have a green lawn and a clean car in the summer.
