Installation of line markers in the most sensitive areas (C2)

ACTION C.2: Installation of high visibility wires markers on the transmission powerlines in the most sensitive bird areas in Lithuania


The action aims reduce bird mortality rate because of collisions with the high voltage electricity lines in the sensitive for bird areas, i.e. Natura 2000 sites or on its vicinity as well as sites with a high concentration of waterbirds – swans, geese and ducks, and cranes, which are worldwide recognized as sensitive bird species from the point of view of collisions with high voltage electricity lines. Although there are no precise statistics on the their collisions rate within high voltage overhead electricity transmission grid in Lithuania, desultory mortality facts of local or wintering and migratory swans, geese and ducks under high voltage electricity lines in the areas of their concentrations show us the significance of that problem. This conclusion can be confirmed by the example from Lithuania when up to 15% of the most numerous wintering Mute swan local populations getting dead because of collision with high voltage electricity wires every year. More detail information on the collisions with electric wires rate on the most important waterbirds concentration sites will be collected during implementation of the ex-ante and post-ante monitoring action (D.2). In many countries bird mortality because of collision with high voltage electricity lines is recognize as especially serious threat for high concentrations of waterbirds as well as souring birds and cranes. Basing on this conclusion and the practice from other countries, specific measures are planned for reduction of rate of bird collisions with electric wires at the Special protected areas, designated for the species from the “high risk group – geese, swans and cranes, its vicinity as well as not protected areas with high concentration of waterbirds.

 

The only possibility to reduce significantly the number of bird collisions with electricity wires on the important waterbird and crane concentration site is evident substantially increasing their visibility. For this purpose, basing on the best practices in other countries, special bird flight diverters of higher visibility will be installed on high voltage overhead electricity lines wires in the important for staging bird areas. Until now, certain type of bird flight diverters has not been selected yet. There are several possibilities to choice one of the number bird flight diverters of pendant type (see attached picture “High visibility wires markers_pendant type”). The particular stuff will be selected during implementation of the project action A.1 – Elaboration of the measures for wires marking and bird protection on the utility poles of the high voltage overhead power lines. During the selection process three criteria will be used: a. firstly, the effectiveness of the impact on the reduction of bird collisions with electric wires (not less than officially confirmed minimum level of 80%); b. possible installation on high voltage wires techniques; c. cost efficiency (both price of the diverter and installation cost). In principle, even “spiral” type diverter could be choose, but except the electricity lines crossing the water bodies, because of costly helicopter service and lack of the capacity of the potential subcontractors to work in poised position on high voltage wires. Requirement for high efficiency of the mitigation measure is based on the conservation objective to ensure favourable conservation status of birds on the sites with high their concentration, i.e. having in mind that even not significant difference in the percentage of the effectiveness might cause quite large numbers of individuals.
Installation pattern of bird flight diverters will be planned and proposed also during the implementation of the of the project action A.1. The number of the installations on wires, for the least segment of the high voltage overhead electricity line, i.e. space between two neighbouring pylons, firstly, depends on the selected stuff and on the practices from other countries as well as scientific research and their recommendations for installation of the certain bird flight diverter. However, the general approach to install the visualization measures on the 40% of the electric wires length, i.e. to leave up to 60% of the wires without installation of the bird flight diverters, should remain. Thus, having in general priciples, which are based on practically implemented and conscientiously tested/ monitored measures in several countries, for our planned 14 segments of the high voltage electricity overhead lines with a total length of around 20 km (see attached pictures „Action C.1, C.2_High voltage electricity transmission lines“, „Action C.1, C.2_Page 1“ – „Action C.1, C.2_Page 15“), at least 1,500 bird flight diverters of higher visibility should be installed on the selected fragments of the certain high voltage overhead electricity lines. Such volume of the planned bird collisions mitigation measures covers all known waterbird and crane staging sites with high concentration of the above mentioned species, which are crossed by the high voltage overhead transmission lines or having such lines in close vicinity. The precise framework for installation of the “spiral” type bird flight diverter measures (definitive boundaries with concrete pylon numbers) will be specified during implementation of the project action A.1. This information will be used for planning of the installation of the later selected type of wires visualization measures – the sequence and pattern of the installation on the concrete segments, their accessibility, cost-effective logistics for installation and etc.
The later selected type bird flight diverters also will be installed on the “zero” leg electricity wires only. Installation on the voltage wires is complicated because of corona effects with makes negative impact on the installation of the hi h visibility bird collision mitigation measures have been selected over water surface only, the visualization measures will be installed using flying facilities there. It might be helicopter or much simple flyer for example, a unmanned glider. The action is planned to start on the second project year, i.e. as soon as concrete high visibility measures for wires will be selected, then procurement procedures on the installation services and purchasing or manufacture of the selected bird flight diverter will be completed, and will be continued during next two years project implementation period. The effectiveness of the installed protection measures will be verified during the implementation of the ex-ante and post-ante monitoring scheme (Action D.2).