Environmental Stewardship
Avian Protection Plan
Osprey like to use power poles for nesting. Sometimes the nests can cause a risk of fire and electrocution. Biologists survey and manage nests within our service area to reduce risks to birds, protect equipment, and to maintain service reliability.
A variety of birds use utility structures without consequence, however, large birds such as owls, hawks, and eagles are at greater risk of electrocution on utility structures. Electrocuted birds may interrupt electric service, start fires, and cause significant equipment damage. In addition, most birds are protected under the Migratory Bird Treaty Act (MBTA), a strict liability act, making it illegal to “take” these protected species. Most bird species occurring in Chelan County are protected under the MBTA. The bald and golden eagles are afforded greater protection under the Bald and Golden Eagle Protection Act. The U.S. Fish and Wildlife Service has encouraged individual electric utilities to develop Avian Protection Plans (APP) to monitor bird electrocutions and collisions and manage them to prevent future incidence. In 2005, Chelan County PUD approved an APP in coordination with state and federal agencies. Chelan PUD is also a member of the Avian Power Line Interaction Committee (APLIC).
The APP aims to reduce bird and other animal caused outages in several ways. First, any incident reported is investigated. Where possible the structure is modified to prevent future incidence. In addition, structures in the surrounding area are evaluated and adjacent poles that may create problems are tagged for modification as well. Through this process, we can better address areas of high use or old line designs that may have inadequate clearances. Lastly, the PUD is changing its construction standards so that newly constructed overhead lines pose less risk of electrocution for birds and other animals. The majority of animal caused outages experienced by the PUD are caused by squirrels.
Chelan PUD has recently concluded a unique survey to determine the potential of fall migrating raptors to collide with portions of a newly constructed transmission line. The Burch Mountain 230kV Raptor Migration Study combined both visual and radar observations to determine flight corridors and altitudes of passing migrants, and how they relate to the transmission line corridor. The pre-construction survey enabled us to determine which sections of the transmission line had a higher collision risk to migrating raptors. Those sections were marked with bird flight diverters during construction. The diverters increase the visibility of these transmission line spans to migrating raptors and reduce the potential for collisions. The post-construction survey will evaluate the effectiveness of the diverters during the 2007 fall raptor migration.