Construction of Thiba Dam that was expected to secure a year-round water supply for the regions’ agriculture is now at 91per cent complete.
The 40-meter tall and 1 km long dam creates a reservoir that will allow a twice per year every year Mwea rice irrigation scheme and the surrounding cultivable area.
According to the project, Engineer Stephen Mutinda, the remaining nine percent work includes connection to the existing road network as well as facilities for water draw-off and safe floodwater drainage.
Mutinda said the project has been completed as scheduled and is now ready for flooding come the rainy season beginning March this year.
“We would have started flooding the facility but the water volume is very low, if we attempt to do so at this time, it will adversely affect the water flow to other areas including the very Mwea irrigation scheme which requires water for the rice,” Mutinda said.
He said a gate valve for the control of the water back to the river is yet to be cleared at the Port of Mombasa.
“We intend to have the gate valve to be in place in the next two weeks in readiness for the flooding in case the rains come early enough. “We expect to fill the dam in only one month if we receive the normal rains expected in this region,” Mutinda said.
He said were it not for the low volume of water in the target river, flooding would have commenced and water ready for the farmers by May this year.
The dam Mutinda said would store the water that will later be released to the farmers to enable them to undertake two crops per year since they will no longer depend on rain-fed agriculture.
He said the project would have been ready even before December last year were it not for the delay in the approval of the master list, which took nine months translating to slow mobilization by the contractor, and in the payment of duties, taxes, and levies.
Mutinda said the inadequate budget allocation by the National Treasury at one time led to the suspension of works, which lasted for about three months from 1 October 2019 to 7 January 2020.
“We are now carrying out final touches and we expect to hand over the project to the government soon,” he said.
The Project Manager James Karanja, said the dam at completion would hold 15 million cubic meters of water, which will be supplied to the farmers within the Mutithi section where the existing scheme is being expanded by 10,000 acres.
Currently, the Mwea Irrigation Scheme has 25,000 acres under rice cultivation but upon expansion will add up to 35,000 acres, which will translate to double production of paddy rice.
“As from this year, rice production in Mwea will double from the current 120,000 metric tons to about 250,000 due to the double cropping,” Karanja told the media.
He said the income from the crop, which stands at Sh9 billion, will also shoot up to three fold to about Sh20 billion per year and improve the wellbeing of the farmers.
The National Irrigation Authority is overseeing the construction of the Dam with the Consultant being a joint venture of Nippon Koei and Gibb Africa and contractor Straback International GmbH (Germany).
Once the dam is completed, an additional 10,000 acres will be put under irrigation in Mwea Irrigation Scheme as well as provide sufficient water for double cropping of the entire 35,000 acres of the scheme per year. The construction of the project started in March 2018.
By Irungu Mwangi