Layout

 

 

 

The project consists in the construction of a toll highway between Dakar and Diamniadio (32 Km) which will also service the new international airport situated 42 km away from  Dakar (Ndiass).

·     32 km from Dakar to Diamniadio

·     2X3 lane carriageways  on the  Malick Sy - Patte d’Oie – Thiaroye stretch

·     2X2 lane carriageways with the possibility to extend it to three lanes on the Malick Sy - Patte d’Oie – Thiaroye stretch

·     Construction of new facilities

o    Malick Sy overpass (toboggan)

o    Patte d’Oie Interchangers

o    Hann Interchanger

o   Reconstruction of the Colobane Bridge

o   Camberene Interchanger

o    Pikine Interchanger

o   La Roseraie overpasses

o   3 underpasses to replace the Pikine Viaduct

o   Thiaroye Interchanger

o    Keur Massar Interchanger

o    Rufisque Est Interchanger

o    Rufisque Ouest Interchanger

o   Diamniadio Interchanger

There are plans to connect it to National Highway1 (NH1) with a 2.36 km long linking rail and an interchanger on NH1

 The project is divided into 2 phases 

1.      Malick SY – Pikine (12 Km)

2.      Pikine – Diamniadio (20 Km)

 

I – PHASE I: MALICK SY – PIKINE

This stretch starts at the junction with Avenue Malick Sy at the « Seven Up » crossroads (junction between National Highway 1 and the old Route de Rufisque) by running along the layout of the old highway.

To ensure the project’s rapid kick-off, the first section from Malick Sy to Pikine (12 km) which includes the 7 km-long Malick Sy – Patte d’Oie stretch and the 5 km-long Patte d’Oie – Pikine stretch is being constructed through government funding

 

1.1 Malick Sy - Patte d’oie highway stretch

Situated in the most urbanized part which is also closest to the centre of Dakar, the concerned section begins at the Patte d’Oie interchanger and extends towards the East, directly to the South of the limits of the existing National Highway (NH1).

 

The Patte d’Oie interchanger facilitates direct movements to the South-East towards the Malick-Sy Highway (in the South) or towards Léopold S. Senghor Airport (in the West). In the East, a pull-off running from the Patte d’Oie interchanger leads to the Highway which is situated directly in the South of NH 1.

This 7 km long Malick SY–Patte D’Oie stretch, which was initially 2 x 2 lanes, is currently being extended to 2 x 3 lanes through government funding. It comprises three interchanger systems:

                      - A highway interchange at Patte d’Oie, with NH1 and the bypass (VDN),

                     - two minor interchangers: the Colobane and Hann minor interchangers.

 

Technical description.

-  7 Kilometers long

-  Roadway with 2 carriageways x 3 lanes+ Emergency parking shoulder + Median strip

-  Three interchangers  : Colobane, Hann and Patte d’Oie

 

1.2 Patte d’Oie - Pikine Highway Stretch

The final design was prepared by SCET Tunisia for this 5 km-long road stretch which is currently being constructed as a three lane dual carriageway. 

On this section, (item 2), the highway layout crosses an occupied area used for residential, commercial as well as industrial purposes. It crosses several major axial highways, including the Cambérène Road, the Pikine-West Road, the Pikine-East Road (Route de la roseraie) and the NH1-railroad intersection

It has two minor interchangers:

They are the Camberene minor interchanger and the Pikine minor interchanger.

 

Technical description.

      Levelling of NH1

-  Length 5km

-  2x3 roadway +  2 carriageways X 2 lanes + Emergency parking shoulder +TPC +

Highway section

-  Length 5 km

-  Roadway 2X3 lanes + Emergency parking shoulder

-  Interchangers : Camberene and Pikine

-  Toll station in Camberene  

 

The National Highway construction works are also meant to provide an alternative to users who do not travel through the highway. The works will comprise protecting the road between Patte d’Oie and Pikine from flooding by maintaining it as a 2 double-lane road, replacing the existing shoulders with pavements at least 2.50 m wide and building parking areas along the road.

 

Cambérène Interchanger

 

On the Patte d’Oie–Camberene section, the Toll Highway runs along NH1 directly on its southern segment, and there are plans to build an interchanger shared by NH1 and the Highway around the Camberene road.

This interchanger is composed of a traffic circle on the NH1 - Camberene Road junction and a bypass to facilitate access from the circle to the Highway heading eastwards.

  

West Pikine Interchanger

 

Between Camberene and the Pikine Ouest exit, the Highway layout continues to run along the Southern limit of NH1, moving towards the South in the environs of the Pikine interchanger (Lobatt Fall), to ensure that the latter is separate from NH1 .

 

Toll station

 

The first one-way toll station (towards the East) will be built between the Camberene and the Pikine Ouest Interchangers.

The toll highway branches off towards the South to simultaneously run across NH1 and the railroad at the level of the Seven-Up junction on a high-position structure, the Pikine Viaduct, and continues to the north of NH1 towards Thiaroye.

 

The proposed highway passes through the junction between NH1 and the railroad where three structures will be built for crossing.

 

Footbridges

 

There are plans to construct footbridges in addition to underpasses embedded in the filling of the engineering works at the level of interchangers.

 

II – PHASE II : PIKINE - DIAMNIADIO

Pikine-Diamniadio highway stretch

This stretch begins at the Seven Up junction in the way of 2 works meant to facilitate the crossing of NH1 and the railway. There are plans to build a third structure for the crossing of the toll highway on NH1. The stretch is 20 km. long.

From Seven Up, the highway crosses NH1 and branches off to its North running towards the Thiaroye Camp by crossing Pikine Irrégulier Sud.

Then in the west of the Thiaroye interchanger, the layout runs along a corridor delving into the urban network and avoiding as much as possible the Bonna aqueduct .

The, while it runs along  the south of Thiaroye Camp, the proposed layout avoids as much as possible the residential area situated in the south of the camp.

In the east of the Thiaroye interchanger, the layout continues further south, the closest possible to the high voltage line, in order to minimize the impacts on the urban network and concentrate the constraining infrastructure in the narrowest possible common corridor.

After bypassing the urban zone, the layout is deviated further north and connected to a limit that runs as close as possible along the laterite road which follows ALG supply pipe, with a view to reducing as much as possible the deforestation in the classified forest of Mbao.

This limit is still in the south of the feeder road up to the Rufisque Ouest interchanger, at less than a hundred meters from the central axis of the supply pipe. Minor changes have been made to ensure that the highway layout is far from the different facilities and obstacles existing near the initial  corridor.

Between the two interchangers built in Rufisque (West and East), the layout continues to the south of the laterite road and the supply pipe, by maintaining a distance of more than a hundred meters from the central axis of the pipe.

From the Rufisque East interchanger to the city of Diamniadio, the layout is directed northwards, along the ALG supply pipe, to avoid the University du Future infrastructure and the city of Diamniadio. While preserving the local development plan approved for this city, the layout requires an interchange which will service it and which is located North-West of the initial position and, more precisely, at the scheduled junction between the extension of the future VDN-East and the highway.

The section presents a cross section (2x3 then 2x2 towards the end) with a 33km standard section and comprises of an interchange system with 5 minor interchangers as well as 19 highway structures.

           

The concept is to build structural infrastructure attuned to current needs but which can be easily extended.

? Technical description

Length of highway stretch : 20km 

? Cross section :

·         Between Pikine (Seven Up crossroads) and the Thiaroye full lane station (opposite camp de Thiaroye)  comprising a 33m platform  in a standard section with 2x3 lanes, BAU  and a TPC

·         Between the Thiaroye full lane station (opposite camp de Thiaroye) and Diamniadio (end of stretch), comprising a 33m platform in a standard section (2x2 lanes), with: 

 

Interchanger systems :

 

- Diamond shaped minor interchanger of Thiaroye

- Keur Massar trumpet  interchanger

- Rufisque Ouest trumpet  interchanger

- Rufisque East trumpet interchanger

- Diamniadio trumpet  interchanger

- Diamniadio linking rail :

- Two carriageways 3.5meters wide

- An underpass crossing the railway lines 

- A trumpet-like minor interchanger link to NH1

 

Operating equipment

- Lighting of the standard section of the highway and the traffic interchangers between PK 4.2, PK 9.750 ,

- Six toll stations: a full lane station in Thiaroye and five stations on the traffic interchangers. 

- Open system toll up to the full lane station in Thiaroye and a closed system thereafter.

 

Thiaroye toll station:

The toll is operated as an open system up to the Thiaroye full lane station and a closed system thereon.