Water supply to city residents is expected to stabilise following the repair of Mwagu water intake along River Chania, Nairobi City Water and Sewerage Company has said.
The company had last week warned of supply interruption on Wednesday and Thursday to facilitate the repair job.
But by yesterday (Tuesday), the supply had not been restored in estates like Buruburu, Huruma, Kayole and Umoja.
NCWSC managing director Nahason Muguna said that the interruption was occasioned by the need to repair the Mwagu water intake, which had been damaged during the long rains.
“There will be a shutdown of the Ng’ethu water treatment plant from Wednesday at 6.00am to Thursday 6.00pm,” Muguna said in a public notice.
Nairobi has been grappling with water shortage for years. The commodity is rationed in most estates.
A masterplan projects that the city will require 1.2 billion litres of water daily by 2035.
NCWSC abstracts raw water from River Chania for treatment at Ng’ethu in Kabete.
Ng’ethu serves 85 per cent of Nairobi with water and is designed to treat water with little turbidity.
The areas hit by shortage for most of last week were the city centre, University of Nairobi’s Main Campus, Coca Cola factory, Jomo Kenyatta International Airport, EPZ-Athi River, estates along Mombasa Road, South B, South C and their neighbourhoods.
Also affected were the Industrial Area, estates along Juja Road, Mlango Kubwa, Naivasha Road, Kikuyu Road, Jogoo Road, Mathare, Eastleigh Airbase, Huruma, Kariobangi, Pangani, Maringo, Buruburu, Bahati and Karen.
The others were the Limuru Road neighbourhoods of Parklands, Ngara, Aga Khan Hospital, University of Nairobi School of Law and City Park, Gigiri, Muthaiga, and Thika Road, Kangundo Road and Outer Ring Road neighbourhoods.
NCWSC technical director Lucy Njambi acknowledged that water supply is yet to stabilise.
“We closed Ng’ethu last week deliberately to do some repairs which are now completed. It will take some days for water to stabilise,” Njambi told the Star by phone.
She said the closure left some of tanks empty and “they will take time to fill up”.
Minor problems like airlocks in the pipes too had to be attended to, she said.
The director said the Ndakaini dam with a storage capacity of 70 million cubic metres was full.
The 65-metre deep dam with a 75-square-kilometre catchment area, including Kimakia and Gatare forests in the Aberdares, supplies most of Nairobi water.
It has an installed capacity of 525,600 cubic metres per day, against the city’s demand of 790,000 cubic metres.
In May, the NCWSC was forced to shut down Ng’ethu treatment works to stop the flow of untreated water into homes.
“There has been increased river flow causing high turbidity in the raw water, which is flowing slurry (semi-liquid mixture of suspended particles in water) suspected to be caused by a landslide upstream,” the company explained.
It said “the raw water flowing into the treatment plant has failed to respond to several types of chemical treatment”.
The supply from Kikuyu Springs and Sasumua and Ruiru dams was not affected.
But the three only supply 15 per cent of the city’s water.