Weaselhead Natural Parks Area Biophysical Impact Assessment
In 2007, ENMAX Power Corporation (EPC) started planning for the replacement of power poles within and adjacent to the Weaselhead/Glenmore Natural Environment Park to begin in February 2008. Upgrading old infrastructure is an ongoing process that we perform to ensure the continued reliability of Calgary's electric system. From spring to fall 2007, we engaged in consultations with stakeholders about this project and committed to a number of measures to ensure public safety and protection of species habitat.
EPC commissioned a professional biologist to conduct a biophysical impact assessment of the project area. The assessment was based on a 30-metre radius of potential disturbance around each power pole to be replaced, with recommendations to minimize potentially adverse environmental effects. To implement these recommendations, construction activities were conducted under frozen conditions to minimize impacts to vegetation and surface land. Another measure involved using helicopter services to install the power poles, thereby avoiding the clearing of right-of-ways for heavy equipment and vehicular traffic. Workers also use all-terrain vehicles on existing paved pathways and enter each pole site on foot to reduce ground disturbance.
Following the recommendations presented in the Biophysical Impact Assessment, we developed an environmental construction operations plan designed to reduce impacts and protect and preserve this sensitive natural area through the life of the project.
Birds and Bats and the Taber Wind Farm
Prior to construction of the Taber wind farm, a bat and bird use and behaviour study was conducted as part of the more comprehensive Environmental Impact Assessment. Subsequently, we initiated a two-year bird and bat monitoring study in the spring of 2007. The study's intent is to document indirect and direct impacts to birds and bats as a result of the Taber wind farm. We also sponsor a bat monitoring study by the University of Calgary which examines the impact of wind farms in southern Alberta.
The 2007 bird and bat monitoring study counts bird and bat mortalities that result from the presence of the wind turbines, and identifies any post-construction modifications in behaviour. A radius of 60 metres around the base of each of the 38 turbines is searched at regular intervals throughout the year. The following table indicates mortalities from March 28, 2007 to January 31, 2008.
| Group
| Observed Mortality |
| Number of Carcasses |
Mortality Rate
(#/turbine/year) |
| Bats |
35 |
0.921 |
| Non-Raptors |
31 |
0.816 |
| Raptors |
0 |
0 |
| Total |
66 |
1.737 |
During the 44 search rounds conducted between March 28, 2007 and January 31, 2008, a total of 35 bat and 31 bird carcasses were detected at the Taber wind farm. Thirty-three of the 66 carcasses were provincially listed sensitive species, including hoary bats (11) and silver-haired bats (22). This research will be incorporated into the larger study being conducted by the University of Calgary, to identify impacts of wind farms on bats in southern Alberta and help identify potential measures that may reduce mortalities.
Osprey Management Program
Ospreys are attracted to utility poles located along the Bow River in the City of Calgary due to the height and vantage point they provide the birds, as well as the proximity to the river. Potential hazards of this nesting activity involve the branches and other materials from the nests contacting the transmission wires, which could harm the birds, as well as cause power outages. To prevent nesting on our power poles, we installed seven platforms 
within the City that provide a safer habitat. In areas of high risk, "raptor guards" are placed on utility poles to prevent the birds from nesting.
The first osprey platform ENMAX installed was at the Calgary Zoo. This led to a project with the Calgary Zoo, which bands the birds to help track them. The osprey web cam was installed to view a nest near the Zoo, which was posted online so that the public could witness the nesting, hatching and feeding of the young osprey.