Focus on Burkina Faso

Focus on Burkina Faso

For the greater part of the African continent, managing water resources and access to drinking water are major challenges. Burkina Faso and its capital Ouagadougou, which experiences frequent water supply cuts, are very much concerned by these issues.

Putting an end to this shortage is the key to the Ziga project. It was launched in 1998 and is now in its second phase. As part of the project for the ONEA, SADE Group is building the main raw and drinking water supply pipes and taking on a particular challenge: to deliver the facilities within 23 months.

 

Ziga, phase 2

 

  • lay an underground cast-iron force main (diameter 1,200mm) for raw water over a distance of 2.6km from the Ziga Dam to the new Ziga drinking water production plant,
  • double the Boudtenga Reservoir, with a capacity of 6,000m3,
  • lay an underground cast-iron pipe (diameter 1,400mm) over a distance of 17.3km connecting the production plant to the reservoir,
  • lay an underground cast-iron pipe (diameter 1,600mm) over a distance of 23.5km from the Boudtenga Reservoir to the outskirts of the city of Ouagadougou,
  • from there, lay 2 branch pipes, one of 7.8km and the other of 10km, to supply the existing water towers,
  • build a new reservoir of 6,000m3.

 

A logistics challenge above all else

 

The challenge consisted in organising regular transport operations for over 10,000 pipes and connections from their point of arrival by ship in the port of Tema in Ghana, in order to supply the installation operations and lay as much as 9km of pipeline a month. This represents no fewer than 1,450 semi-trailers transporting the 37,000 tonnes of pipes and connections to be installed by the teams.

 

 

Some specific challenges…

 

The first obstacle was the rainy season, which was particularly intense.

An additional complication was the need to cross main roads. The pipe jacking technique was chosen to lay the pipes under the two roads: one using a steel sleeve (diameter 1,800mm) under the RN4, the Niger road, and the second a steel sleeve (diameter 1,600mm) under the RN3.

A 110m-long reinforced concrete bridge was also built to carry the pipe over an existing canal.

 

 

A strong environmental commitment…

 

The work was always going to have an impact on forest resources, with the need for deforestation along a part of the route of the pipeline. Aware as it was of the situation, SADE Group rolled out a series of measures to significantly reduce the environmental impacts of this large-scale construction project.

An impact study was conducted to make an assessment of the forest resources that might potentially be impacted by the work in the province of Oubritenga. This systematic inventory showed that some 24,000 trees of 59 species were destroyed during the works.

To offset this, SADE Group launched a vast tree-planting operation. By the terms of an agreement signed between the developer of a reforestation site and SADE Group, 34,951 seedlings were planted in an area of 13 hectares about 45km from Ouagadougou, along the route of the 1,400mm-diameter pipe.

SADE Group is proud to be contributing to improving access to drinking water in Ouagadougou, a city that is constantly growing. These new facilities will make it possible to meet demand until 2030.

 

 

 

 

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