Design for the rehabilitation of asphalt roads and earth roads

Country

Niger

Name of Client

EDF National Authorizing Officer

Financing sources

EDF

Association

ART & GENIE (member)

Duration

05/2013 - 11/2015

Project Description

Lot N° 1:                Lot 1A: Tchadoua – Tessaoua - Takeita (142 Km)

Lot 1B: Maradi-Dand Issa –Nigeria border (56 Km)

The section of the Tchadoua – Tessaoua – Takeita asphalt road, rehabilitated in 1987 by the firm Oumarou Kanazoé, presents a cross section of 8 m, with 6 m of carriageway paved with bituminous concrete of 4-5 cm and unpaved abutments with an average width of 0,6 - 1 m.

The first section of this road is clearly defined on site by the end of rehabilitation works of the section Guidan Roumdji – Tchadaoua carried out by the firm Sogea-Satom in 2004. The rehabilitated road has a width of 9 m with 7 m of paved carriageway and abutments of 1 m paved with single surface treatment.

The section of the paved road Maradi – Dan Issa – Nigeria border - Takeita, rehabilitated in 1998 by the firm SATOM, presents a cross section of 9 m, with 7 m of carriageway paved with double surface treatment and upaved abutments with an average width of 0,6 - 1 m.

The first section of this road is not clearly defined on site, since the 56 km stated for this part of road in the ToRs are not real. In fact, the distance between the exit gate of Mardi towards Dan Issa and the Nigeria Border is 45 km. Even adding the crossing of the town of Maradi up to the triangle junction with the RN1 road, Guidan Roumdji - Zinder (approx. 4 km), the whole distance would not exceed 50 km. The Ch 0+000 of this section will be defined with the main contractor and the Regional Directorate during the execution of the design.

Lot N°2: Zinder – Tanout (156km) - Tanout -  Eliki - Pk 227  (71 km)

The section of the paved road Zinder – Tanout (156km), rehabilitated in 1987 by the firm Oumarou Kanazoé, presents a cross section of 8/9 m, with 6/7 m of carriageway paved with double surface treatment with open-graded aggregates and unpaved abutments with an average width of 0,6 - 1 m.

The first part of this section is located in the town of Zinder. The part crossing the town is completely lacking of sidewalks and parking areas, making traffic particularly complex, especially during nights.

Lot N. 3: In Gall-Tassara-Tchintabaraden-Tillia-Mali border for a total of 520 km

The project consists in the construction of a modern earth road (platform width 10m, defined gauge drainage structures), In Gall-Tassara-Tchintabaraden-Tillia-Mali border road with a length of 520 km. The itinerary is currently composed by tracks without any kind of planning or earthworks. The only existing structures are some aprons allowing to cross some critical points. Various areas are inaccessible during rainy season. The main objective of this study is, therefore, to develop those areas by improving access to health centers, schools, markets. The study will envisage a future paving of the road axis.

Services Description

PHASE I: Conceptual design : Existing data collect, visual diagnostic of road degradation, layout study, preliminary survey of geological and hydraulic situation, road diagram.

PHASE II: Preliminary design APS : Topographic study, geotechnical study, conception and dimensioning of the carriageway, hydrologic study, hydrogeologic and hydraulic study, economic study, traffic study, environmental and social impact study (EIES).

PHASE III: Final design (APD) : Definition and detailed design of the road and its structures, bill of quantities, reporting, final design dossier, preparation of tender documents.