Outline Schematic Layout

Capacity Assessment and Performance Modelling studies are being carried out to determine if single or double track infrastructure is to be provided for either current or future operating requirements. In some cases, it may be prudent to construct the line initially for single track, but with passive provision for future doubling.

The passenger service developed above makes certain demands upon the infrastructure, most notably where trains are due to pass. However, this is an iterative process, and costs can be reduced if double‐track is avoided in areas where it is relatively difficult to provide.

Train graphs have been produced for sections of the line to highlight the issues. These graphs plot train position by time of day, with trains travelling away from Addis having lines sloping upwards and those travelling towards Addis having lines sloping downwards.

At this early stage, with freight volumes still unknown, the line between Modjo and Shashemene has been assumed to be double‐track. However, the analysis shows that it is possible for a difficult‐to‐construct section between Arsi Negele and Shashemene (km 221 ff) to be single‐ track, whilst still permitting the operation of up to hourly passenger services and some slower freight trains (the services shown in thicker light and dark blue lines).

Given the train service frequencies envisaged, analysis suggests that it will be sufficient for the branch line to Awasa to be largely single‐track.

Analysis is ongoing for the section between Shashemene and Konso, but a mix of single‐ and double‐track is likely.

South of Konso, traffic is expected to be relatively light; indeed, it is not clear whether any passenger service would be justified in the early years of operation. However, there will be through traffic to/from Kenya, likely to amount to a few trains per day. We have therefore examined the operability of a single‐track system, especially in a number of areas (marked in red on the above graph) where construction appears less straightforward. Running six trains per day in each direction seems eminently possible with a single‐track system with a passing loop at Yabelo and a section of double‐track between Mega and Godebero; this latter also provides some degree of operational resilience in the short‐term. Should traffic levels rise, additional passing loops can be provided.

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