Engineering design for the rehabilitation and maintenance of the Trans-Saharan corridor (RN 11 Nord) between Agadez and Zinder, section Tanout-Tiguidit (227 km)

Engineering design for the rehabilitation and maintenance of the Trans-Saharan corridor (RN 11 Nord) between Agadez and Zinder, section Tanout-Tiguidit (227 km)

Country

Niger

Name of Client

Ministère de l'Equipement

Financing sources

World Bank IDA

Duration

04/2020 - 08/2020

Project Description

The subject of this study concerns the rehabilitation of RN N. 11 between Tanout and Tiguidit: Since 2013, the section between Tanout and Tiguidit (227 km) has deteriorated even more and urgently requires rehabilitation / reinforcement. The European Union financed the studies at the Detailed Preliminary Project (APD) level for two sub-sections of the road, in particular:

  • For section between Tanout and Silika (90,76 km)
  • For section Abalama – Tiguidit (40 km)

Given the time elapsed and the additional degradations of the road since 2013, these studies now require updating, particularly with regard to the technical solution to be adopted for the rehabilitation / reinforcement works and the volume of work required.

  • Abalama and Silika of 86.24 km, realized by SOGEA SATOM since 2004. No recent study is available.

 

Beyond the rehabilitation of severely degraded sections between Tanout and Tiguidit, it is planned to possibly combine future rehabilitation works with one or more multi-year maintenance contracts, preferably under the “Road Market with Obligations for Results” modality (GENiS/OPRC ) using the tender dossier model developed by the World Bank.

The study also provides for a road safety assessment on the Tanout - Tiguidit axis, with the location of black spots, an analysis of road accident data and the implementation of measures to improve safety. Specific surveys were carried out with users and with local authorities.

 

Road project geometry:

  • Total road length: 227 km
  • Carriageway width: 10,2 m
  • Shoulders width: 1,5 m

Road quantities:

  • Earthworks (fill/cut): 1 000 000 m3
  • Sub-base : 180 000 m3
  • Base course : 400 000m3
  • Wearing course ES/BB

Structures:

  • Culverts (box/pipe): 180

Services Description

  1. Task A : Engineering Design for the rehabilitation of the road axis between Tanout and Tiguidit (227 km)

    Task A.1         Review of existing studies and other existing documents

    Task A.2         Data collection and first diagnostic of degradations

    Task A.3         Traffic study

    Task A.4         Topographical study

    Task A.5         Hydrological and Hydraulic study

    Task.6             Adaption to climate change

    Task.7             Realization of complementary surveys

    Task A.8         Definition of technical solutions for rehabilitation/reinforcement

    Task A.9         Road Safety Audit

    Task A.10       Detailed Engineering Design

    Task  B : Economic feasibility study

    Task C : Study for the pluriannual maintenance of the Trans-Saharan Corridor between Agadez and Zinder (450 km)

    Task D : Elaboration of the tender dossier