@FRM2011, The first feasibility study for Thwake Multipurpose dam was done in 1953 under colonial government. The second one was done in mid 1980s.

After bringing in a part financier, the civil works for Phase 1 were meant to start in June 2014 and complete in 2019 but somehow got delayed,

For your information, when the Thwake dam construction is completed to the last Phase it will have a total storage capacity equal 2.4 billion cubic metres of water for consumption, irrigation and 20MW HEP power generation.

There are two frames of mind we are facing in our country today: Politics and development and politics of development. On one hand, a tunnel is to be constructed linking some rivers and supposed to collect a given amount of water for storage at ndakaini. From there, a new water treatment works is to be built, ensuring that the supply to nairobi will rise to cater for demand. A politician comes up saying they drew those plans while in government thus should get credit for the same, next day he says the plans would cause desertification downstream as all water would be diverted away from the river. Which politics is this, as per the above headings?
The northern water collection project is ongoing ( https://www.capitalfm.co...-140mn-litres-of-water/ ). this would solve part of the problems of Nairobi and water, but this alone will not help. I feel the blunder back then was allowing for low-density population areas in nairobi to be converted into high density population areas (Kilimani, Lavington, Lileleshwa, etc) instead of venturing out of nairobi by ensuring there are adequate and on-time transport solutions to cater for the guys living outside nairobi (Guys from thika, ruiur, machakos, Limuru/naivasha, etc), plus water and electricity.

‘General Erskine in a letter to his wife says of the settlers, ‘they are jumped-up middle class sluts and harlots, who for generations have brutally exploited the land and labour of an indigenous people who are finally striking back. I hate them all, they are virulent racists and not fit to rule over anything let alone a British colony.’

Which main rivers will be tapped to fill the Thwake dam?

Hi all,

I am fully convinced beyond any shadow of doubt that the leaders we have are more of clowns and knows very little of what they are required to do. After the energy sector,now it is water sector which is now reeling under the weight of myriad problems ranging from lack of water to the mismanagement of the little that is available…..you see Chality Ngilu stands up and says that Kenya is the most water-poor country in the world and blames the situation on drought and illegal connections. The following day her junior officer Permanent Secretary Engineer David Stower opens his baggy mouth and tells us that the current shortage of water being experienced is due to the drought..what in God’s name are these two idiots treating us to??? The usual sparghetti talk??? Drought has got nothing to do with the current acute water shortage as explained below:

Let us first briefly examine the status of the existing water supplies to Nairobi:

1. Ndakaini Dam

The dam was commissioned in 1990 and is located in Thika district of Central Province. It is the largest of the four Nairobi water sources (supplying 84% of the water consumed in Nairobi) with an installed capacity of 70 million m3 deriving its replenishment from river Chania whose source is in the Aberdares. The designed daily out flow is 440,000 m3 but under normal conditions the extraction rate recorded at the Ng’ethu Treatment and Distribution station is 376,000 m3. This translates into an 85.5% utilization.
As at August 2009,the dam was only 36% full i.e 25 million m3. Under normal operating conditions it would take just 66 days to empty the dam assuming that there is no water flowing into it. The current inflow or rate of replenishment is only 21,000 m3 against an outflow of 86,400 m3. The nett outflow is therefore 65,400 m3. Assuming the current conditions persist and that the inflow and outflow rates are maintained,the dam will be empty in 382 days! The dam was constructed to service the Nairobi water needs at its (dam’s) peak upto 2010 if then the flow of water into the dam continued uninterrupted. Additional capacity was to have been developed by the year 2005 to maintain the dam at its peak. A proposal was made to link the rivers Maragwa and Mathioya to the dam through a tunnel. Nothing has been done to date.

Started 12 years later

2. Sasumua Dam

The dam was commissioned in 1956. It is located in Kinangop,Nyandarua South in Central Province. The dam supplies 11% of the water consumed in Nairobi and has an installed capacity equal to 16million m3. The dam draws its water from streams emanating from the Aberdares forest. When the dam was first constructed it was meant to serve the white settlers in upper Nairobi,that is Lavington,Hurlinghum,Westlands,Ngong Road,Langata,Ngumo,etc. The designed daily output of the dam is 59,000m3. And the output recorded at the treatment works is 41,000m3. This is equivalent to 69.5% utilization.
As at August 2009,the dam had only 4million m3 of water,i.e 25% full. The dam was badly damaged by floods in the year 1999 and it is currently undergoing rehabilitation.

3. Ruiru Dam

The dam was commissioned around 1953. It is located in Githunguri subdistrict of Kiambu District in Central Province. The dam is fed by river Ruiru which has its source in the Aberdares forest. The dam has an installed capacity of 3million m3. The design extraction capacity of the dam is 22,000m3 per day,but the recorded output at Kabete Water Treatment Works is 21,000m3. This is reflecting a healthy utilization of 95.5%.

4. Kikuyu Springs
This water supply was constructed in 1906 by the Imperial British East Africa (IBEA) and was later sold to Nairobi Municipal Corporation in 1922. The installed capacity for this water supply has never been quantified. It has design extraction capacity of 4000m3 per day and the average recorded at the water treatment works is 4000m3 per day meaning that it is utilized into its full capacity.

The Picture

At independence Nairobi was receiving just about 66,000m3 per day which by any standards was more than enough as the population was very small,about 300,000 and the average daily demand per person was 0.22m3 or 220 litres per day.
As at the fist census carried out in 1969 the population of Nairobi was about 520,000. At this population the water was still abundant . The average daily demand per person stood at about 200 litres.
Ten years later in 1979 the population had risen to about 800,000. The existing water supplies were experiencing the demand pressure because the few water boreholes which had been sunk to supplement the main supplies could not completely eradicate the shortfall. With a demand of over 180,000m3 and a supply of only about 100,000m3 the stage was set for an early sign of crisis. The amount of water available per person was only 125 litres per day. So some areas mainly Langata and Eastlands started having some water problems of occasional unofficial rationing which was just mild.
Ten years later in 1989 the population and risen to about 1,400,000. The water demand in Nairobi stood slightly higher than 320,000m3. The then existing supply could only satisfy just about 120,000m3. The average amount of water available per person was 86 litres per day. With this scenario a half of Nairobi was not receiving adequate water as per WHO basic requirements. Apart from Lang’ata and Eastlands many other suburbs were sucked into the water don’t haves list.
Ten years later in 1999 the population had risen to about 2,200,000. The water demand was then at about 600,000m3 against a supply of about 450,000m3. The sharp rise in demand was because some other areas outside Nairobi started getting connected to the Nairobi supply. These areas include Athi River,Kitengela,Mlolongo,Ruai,Rwaka etc. At this time some Nairobi suburbs could span upto three weeks without a drop of water and again the main casualties were Lan’gata,Otiende,Kibera,Kariobangi,Umoja,Donholm,Savanna. A chunk of the available supply went to these peri-urban areas leaving the genuine Nairobi residents with very little water. The daily water availability stood at 130 litres per person. The improvement here was due to the commissioning of Ndakaini dam.
Come 2009 and the situation is a full blown crisis. The current daily demand from a population of 3,000,000 plus another approximately 3,000,000 from peri-urban areas is standing at about a 1,000,000m3 and the supplies are already stretched to their limit of 450,000m3. And is meant to serve close to 6 million people!!! The daily water availability stands at 75 litres per person!!! Against a satisfactory daily demand or requirement of 200 litres per day!!! What I mean here is that the existing water resources cannot even satisfy just a half of the Nairobi’s current demand if they operated at full output capacities!!!

The Situation

It is really chilling to know that at the moment we have actually run out of water completely!!!...reason… as per the demand of 1,000,000m3 of water,for a population of about 6,000,000,the average demand per breathing person is 0.17m3 or 170 litres per person per day.
Under the prevailing circumstances,the gross output from the supplies is a paltry 150,000m3 per day serving the same population of 6,000,000. This means that to each person only 25litres per day is available!!!!!...just one 25litre jerrycan!!! With only one jerrycan of water per day per person Nairobi has completely run out of portable drinking water…this is a disaster!!!
It can be clearly seen that the amount of water available per person has declined through the years because there has been no expansion of the existing water resources and no new ones have been developed between 1956 and 1991 when the Ndakaini dam was commissioned and after 1991. In post independent Kenya only one water resource for Nairobi has been developed.
The only time that the Nairobi residents enjoyed water in abundance was before 1979 and between 1991 and 1999 where the daily water availability per person was above 100litres per day!!!

Landlord, was Sasumua ever completed? It would be nice to have a map showing the suburbs served by each dam. Looking at how much money we spend on nonsensical stuff like the legislative summit currently happening, you have to wonder, who bewitched us?

The Tunnel from River Maragwa was done a few years ago.....The pipe is tapped from some place Karurumo