Project Info

Biodiversity Offset Strategy for the Trans-Anatolian Natural Gas Pipeline

Cinar Engineering Consulting Co

Southern Europe


Golder has developed an innovative approach to identify, evaluate, and deliver a biodiversity offset strategy for the Trans-Anatolian Natural Gas Pipeline (TANAP). It is a new approach which could be replicated for other similar projects worldwide, helping clients to create business value while protecting and enhancing biodiversity and ecosystems, joining the private sector to conservation.

The pipeline is designed to transport natural gas from BPs Shaz Deniz gas project in Azerbaijan, and other fields in the South Caspian Sea, to Turkey and Europe. It will extend 1800 km across the entire country of Turkey, from Georgia in the east to Greece in the west, crossing nine distinct ecoregions along the way, each with multiple biodiversity elements.

TANAP is committed to managing the potential effects of the Project on biodiversity by implementing the biodiversity mitigation hierarchy of first avoiding, then minimizing and rehabilitating, and finally offsetting biodiversity impacts. The mitigation hierarchy is applied to achieve either a no net loss (NNL) or net gain (NG) outcome for biodiversity.

The first three steps of the mitigation hierarchy have been considered by TANAP through project design, Environmental and Social Impact Assessment (ESIA), and Biodiversity Action Plan (BAP) processes. Golder designed the fourth element of the mitigation, the offset strategy, involving the calculation of net habitat losses, net gain and the identification of offset measures to compensate for biodiversity loss, with the aim of achieving an NNL or NG outcome. The strategy was developed in accordance to the requirements of the European Bank of Reconstruction and Development (EBRD) Performance Requirement 6 (PR6) and the International Finance Corporation (IFC) Performance Standard 6 (PS6) “Biodiversity Conservation and Sustainable Management of Living Natural Resources”.

An offset accounting method to calculate residual biodiversity losses, and gains generated by offset actions, was developed. Our approach involved using large datasets integrated in a GIS environment to ensure that losses and gains were calculated within the same geographical ecoregions, rather than on the totality of the project. This is a like-for-like concept involving localised species, natural communities and environmental conditions.

This accounting method demonstrates NNL or NG, taking into account the pre-existing disturbance of each habitat type within the ecoregions, the suitability of each habitat to host the species of conservation concern, the level of conservation significance of certain areas across the Project, and the benefits of rehabilitation activities undertaken by TANAP.