Posted on Wednesday November 18, 2015 at 01:46PM
When you look out over the lake and see the calm surface, it seems so still, like glass, like there’s nothing happening.
Take a closer look --- under the surface there is abundant life: large fish, minnows, water bugs, small shrimp, zooplankton. It’s a busy aquatic world, summer and winter.
There’s a lot of Action – Just like the aquatic creatures that we don’t notice until we look, much work is happening to address blue-green algae at Pigeon Lake.
We’re on pace to get required scientific data from sediment and water testing. There’s analysis that must occur to obtain regulatory approval for any in-lake treatment. APLM representatives have also participated in the Watershed Management Plan since it began tackling topics in 2012, with recommendations made on a major topic every year since. Integrated management of the lake and surrounding watershed is needed by the public, summer villages and stewardship associations.
There’s a lot of Options - Science and research is one of the necessary steps involved to determine appropriate in-lake option(s).According to experts, some options we will NOT PURSUE are:
• Dredging – which directly removes phosphorus, difficult to know where to target, or how deep (sampling shows nutrient concentration to 20 cm), it can take from 2 - 10 years to reach a new water balance after dredging, and there are high costs of actual operation and removal.
• Algaecides – used for 40 years, however, need to consider whether or not whole lake treatment is required, the origin of products and transportation costs if a large volume of products is required; other costs include boat travel, material handling, delivery, staging; would need to gain support of regulators.
• Oxidization - this short-term option for esthetic purposes disrupts cyanobacteria cellular function. It is a possible strategy/short-term relief and rapid control of algal blooms or mats. However, there are potential toxic effects on aquatic biota and it does not address the issues of nutrients. This option would require further testing from scientific and regulatory perspective.
• Water Importation - Pigeon Lake has been found to have a water ‘turn over’ every 100 years compared to, say, Sylvan Lake which has water turn over 4 times a year. While the option of importing water from the North Saskatchewan River has been considered, the volume of water required and likelihood of affecting biota and increasing phosphorus with imported water mean this option is not feasible. Our Alberta Environment representative recommended APLM not pursue this option further unless new information was provided. No further work is being undertaken or planned on this option.
• Alum – has been successful, but Phoslock has 300 times the ability to fix phosphorus.
See information about Options we are pursuing, Phoslock and Bio-Manipulation, in our up-coming Newsletter.
There’s a lot of People involved - the public participates through the PLWA --- with over 700 on distribution list --- in meetings, events, on-line surveys; Summer Village residents participate through AIMs, and officials at PLWA leadership meetings APLM, ALMS, ASVA; members of and volunteers with PLWA meet at the AGM, regularly for WMP, reporting, reviewing, recommending, developing education materials.
• Community enthusiasm is welcomed and needed for volunteer activities of PLWA;
• With the information here we seek to bridge gaps --- letting the community know that APLM is acting, momentum is strong and things are happening; and,
• A more formal public information campaign can be developed and implemented when we move forward with particular in-lake treatments.