Thwake Multipurpose Dam

Thwake Multipurpose Dam

Makueni, Friday, July 9, 2021

This is a bankable project, says President Kenyatta as he tours Thwake Dam promising massive river clean-up

President Uhuru Kenyatta on Friday, July 9, 2021 toured the ongoing construction of the Thwake Multipurpose Dam where he registered his satisfaction with the progress.
During the visit, the Head of State promised that the Government together with key agencies, will embark on a rigorous clean-up exercise of the Athi River and main water sources expected to feed the dam under construction.
The program – done in four phases – is expected to benefit at least 1.3 million residents drawn from rural parts of Makueni, Kitui and Machakos counties.
“The State will ensure all environmental issues are tackled fully. The National Environmental Management Authority (NEMA) will work and safeguard upstream pollution and ensure the water sources are clean before wananchi start enjoying the water,” said the president who was accompanied by a host of leaders from Ukambani region led by former Vice President Kalonzo Musyoka and former Prime Minister Rt. Hon Raila Odinga.
The Head of State added that it is the right of every Kenyan to get clean and safe water for drinking and domestic use.

“Once we are done with the clean-up exercise for Nairobi Sewerage System, the city will be clean hence water coming to this dam will be good.”
This project, he added, will benefit millions of residents from these regions and “we will ensure it is completed in good time so that by June 2022, we will come back and officially commission it. Residents want good infrastructure, power, employment opportunities, good roads.”
The Ministry of Water, Sanitation and Irrigation is committed in improving sanitation upstream of the project by investing in a number of interventions – both long, medium term and short term. This strategy is on course and already being carried out by an Inter-Agency Technical Committee on Athi River Protection and Pollution Control and Management.
NEMA and Water Resources Authority (WRA) have already identified and mapped out pollution hotspots. Meanwhile, Athi Water Works Development Agency has also put up 19 ablution blocks in Kibra slums and in partnership with Mazingira Yetu undertaken River clean up exercise, while WRA has pegged some riparian areas and is in the process of pegging more areas for protection. There is an ongoing project of sewerage connections in Kasarani area too.

Progress on the key activities include excavation works on water diversion Tunnels A and B which are complete. Currently lining of the tunnels is ongoing at 50% done. Tunnel A is 731 metres long with a diameter of 12 metres and Tunnel B is 797 metres with a diameter of 12 metres. Approach Channel excavation is at 96%, Outlet Channel excavation is at 98% while excavation at discharge channel and power house is complete.
Spillway excavation is also complete while the Dam Axis (embankment) excavation works is ongoing at 85%. Rock fill at the embankment is ongoing at 13.7% and plinth construction is at 47%. The two (2) coffer dam designs are under review and construction is scheduled to commence in September 2021. Construction of the employer and engineer’s permanent site offices completed and occupied.

The program comprises a multi-purpose dam for Water Supply, Hydropower Generation and Irrigation Development. It will also provide regulation of flows on River Athi downstream of the dam for flood control and drought mitigation. The program will be implemented in four phases.

Phase will involve construction of an 80.5m high multi-purpose dam with storage capacity of 688 Million cubic metre and associated preliminary works located one Kilometre downstream of the confluence of Thwake and Athi Rivers. It is an embankment dam with an approximate maximum height of 80.5 m covering an area of around 9,217 acres, with catchment spanning about 10,276 km2;

Phase 2 will see the development of Water Supply, Sanitation & Waste Water Infrastructure to supply estimated 150,000 m3/day of treated water to approximately 1.3 Million people drawn from the rural areas of Kitui and Makueni Counties and Konza Techno City in Machakos County

In Phase 3, the program will involve development of hydropower generating system with an installed capacity of approximately 20 MW while in Phase 4, there will be development of Irrigation Scheme to ultimately irrigate 40,000 hectares (approx. 100,000 acres) of land

Other leaders who accompanied the president were Water, Sanitation and Irrigation Cabinet Secretary Mrs. Secily Kariuki, Devolution Cabinet Secretary Eugene Wamalwa, Defence Cabinet Secretary Amb. Monica Juma, Water, Sanitation and Irrigation Principal Secretary Joseph Irungu, Makueni County Commissioner Maalim Mohammed, State House Comptroller Kinuthia Mbugua, Governors Charity Ngilu (Kitui), Prof. Kivutha Kibwana (Makueni), Alfred Mutua (Machakos), Transport CAS Wavinya Ndeti a mong others.