Excavation of the 11.7km Northern Water Collector Tunnel is complete and contractors have only to line up the underground passage before commission in June 2020.
Construction of the tunnel project — implemented by the Athi Water Services Board in Murang’a County — is currently 80 percent complete.
The Sh20 billion tunnel is funded by World Bank among other development partners and draws water from three rivers, namely: Irati, Maragua and Gikigie.
Once operational, it is expected to increase water volume at Ndakaini Dam by 140,000 cubic meters daily.
The tunnel will also be the major source of water for Nairobi City County and its environs.
An Athi Water Services Board engineer, Mr Alphaxard Kitheku, on Friday told Murang’a County Development Implementation Coordination Committee (CDICC) that the contractor is currently working to complete lining of the tunnel.
Kitheku said construction of two intake weirs at Maragua and Irati are ongoing whereas the third intake at river Gikigie will start early 2020.
“Construction of Irati River intake is at 98 percent complete and Maragua River intake weir is at 20 percent,” said the engineer.
The project was expected to be completed by December 2019.
Further, Mr Kitheku said the construction of raw and treated water transmission pipelines from Ndakaini Dam to Kirogo water plant and Nairobi is ongoing.
The engineer said that 15.5km out of the total 54km of pipes have been laid.
“The project aims at conveying the raw water from Ndakaini to Kirogo Water Treatment Plant and treated water from Kirogo to Gigiri reservoirs in Nairobi,” he said.
