Water level at Ndakaini has dropped due to short rainfall last year and beginning of this year. [Edward Kiplimo/Standard]

Government has ordered an investigation into the unusually low water levels in Ndakaini Dam amid the ongoing heavy rains including in its catchment areas.

A task force headed by Eng Samuel Halima will probe situation that has caused panic among millions of residents in the city and its environs who rely on it.

Halima’s committee is expected to report its findings within 60 days, even though initial indications point to deliberate interference with water flow upstream.

Winnie Guchu, the Chief Administrative Secretary in the Ministry of Water and Sanitation, yesterday led an inspection tour of dam and the rivers that feed into it.

She cited that the water shortage in Nairobi linked to the levels in Ndakaini were a huge cause of concern, especially with the heavy rains.

Ms Guchu was accompanied by Joseph Irungu, the Principal Secretary in her ministry, area legislator and Members of the Nairobi County Assembly.

Irungu said the findings of the taskforce will inform how the dam will be managed in the future.

“We have given the taskforce two months to do a thorough probe on all issues including diversions and leakages, and must involve the local community,” he said.

Among the proposals suggested is to plant more trees in the water catchment areas as a longer term solution to restore the depleted forest cover.

Involvement of the State comes after the management of the dam repeatedly gave conflicting and unconvincing explanations on the surprising water levels.

Ndakaini dam provides at least 80 per cent of the water needs for Nairobi, to highlight its importance in the supply matrix which also consists Sasumua and Ruiru.

By yesterday, the dam was less than half full even though heavy rains have been received for nearly two months.

In contrast, the significantly smaller Sasumua and Ruiru dams were full.

A report of the Nairobi Water and Sewerage Company shared with Ms Guchu’s team heaped the blame on various factors including diversions upstream by farmers and leakages.

It also claimed that more rainfall was received in Southern part of Nairobi since last month than at the Aberdares – the source of the rivers feeding the dam.

“The drought situation affected water supply since January 2017 to date. Under normal circumstances, Ngethu/Ndakaini system provides about 440,000 to Nairobi County,” the firm said.

Owing to the low water levels, the firm has stopped abstraction to allow the dam to refill, meaning only the smaller dams are supplying the city.

Philip Gichuki, the former boss at the Nairobi Water Company, told the Standard that the prolonged drought of last year meant that the ground in the catchment areas had dried significantly and would naturally absorb most of the rainfall.

“Water started running into the rivers long after the rains started because the ground has to be saturated first,” Eng Gichuki said, in reference to the “thirsty” soil in the catchment areas.