Biodiversity

Hydro

At our hydro operations, we incorporate the reduction of environmental impacts into routine maintenance activities. During shutdowns at our hydro facilities we are occasionally required to interrupt water flow to complete the approved activities.

• To minimize fish being stranded we slowly reduce water outflows during the period preceding the outage, to allow fish to move to deeper areas of the river.
• We recover stranded fish that were unable to move to deeper areas, and transport them to deeper sections of remaining pools or channels.

Over the years, reductions in the number of stranded fish have been observed at our facilities.

In 2009, working closely with Parks Canada, we completed a habitat compensation project in the Cascade River below our Cascade Plant, within Banff National Park, to offset fish habitat loss that may have occurred from maintenance on the dam. Three areas of fish and benthic invertebrate habitat enhancement were created using floating tree cover. All work was completed by hand and walk-in access to reduce any potential environmental impacts.

Bats and wind turbines

A four-year study initiated by TransAlta has found a way to reduce bat deaths from wind turbines by up to 60 per cent without significantly reducing the energy generated from wind farms. The study, published in 2009 in the Journal of Wildlife Management, demonstrates that slowing turbine blades to near motionless in low-wind periods significantly reduces bat mortality.

The study was co-authored by University of Calgary biology professor Robert Barclay, PhD student Erin Baerwald and TransAlta’s Jason Edworthy and Matt Holder.

TransAlta applied the low-wind mitigation strategy to the 38 turbines in the Pincher Creek, Alberta, study area. Based on the results, we may expand this practice to other wind farms with high bat mortality rates.

Biomonitoring in Alberta

In the vicinity of our Alberta coal operations, in partnership with Capital Power Corporation, we monitor several ecological receptors annually. This extensive monitoring program will further the understanding of how soil, vegetation, water and wildlife are affected by the different emissions and activities associated with our facilities. Monitoring will cost close to $2 million in 2010.

Our studies include monitoring of fish, raptors, other birds, voles and amphibians. We also perform aerial surveys of ungulates (such as deer) and track collisions between ungulates and vehicles in the regions surrounding our power plants.

In 2009, monitoring was conducted on peregrine falcons, cooling pond water quality, and air including acid and mercury deposition. In 2010, we will be moving to a five-year cycle for all biomonitoring.

Fish habitat in Washington

In 2008, TransAlta partnered with Lewis County in Washington to construct three fish passage enhancements on two waterways. Final restoration of the sites was completed in 2009. With the installation of the new fish passages, approximately 15 kilometers of salmon spawning habitat were established. The enhancements also provide off-channel alcoves, or resting areas, for the fish swimming upstream to spawn. The projects were part of TransAlta’s operating permits, to mitigate impact to area wetlands resulting from mining activities.