The government has assured Ukambani residents that the heavily polluted Athi River will be cleaned up within the next four years before the completion of the multi-billion shilling Thwake Dam.
Water Principal Secretary Joseph Irungu Tuesday said efforts are underway to ensure that the Sh64 billion dam, which is being constructed at the boundary of Kitui and Makueni counties, will not be a reservoir of sewage.
Mr Irungu said the government had already tasked the Water Resources Authority (WRA) to map out pollution spots along the river before a major clean is undertaken.
This, The PS said, will ensure that the dam doesn't collect contaminated water, which is unfit for human consumption, as shown by an ongoing Nation exposé.
"The pollution of Athi River, which we have seen in the media recently, is a genuine concern. We want to assure you that Thwake Dam will not collect polluted water We shall clean up Athi River by the time the dam is completed in the middle of 2023," Mr Irungu said.
The PS visited the dam site at the confluence of Athi and Thwake rivers amid concerns by residents and environmental and health experts that the high levels of toxins detected upstream will shadow the benefits of the Vision 2030 project.
He said the project was slightly behind schedule and urged the contractor -- China Gezhouba Group Company -- to speed up the works.
The project is supposed to be 28 per cent completed as per the government's timelines, but it is at 25 per cent, according to Mr Irungu, who exuded confidence that it will soon be on course.
Upon completion, the dam is expected to hold 700 billion litres of water, which will be used for domestic purposes, irrigation, and generation of electricity. Water from the dam is also expected to run the proposed Konza Technocity.
Mr Irungu was accompanied by senior ministry officials including the project consultant David Kimingi, and Tanathi Water Works Development Agency CEO Tito Mwamati.
The tour came at the backdrop of the Nation expose, which shows that Athi River -- the dam's primary water source- is heavily polluted with high levels of harmful contaminants and bacteria. The exposé, which has been running for the last two weeks, has alarmed residents that the water to be collected at the dam will be unsafe for human use unless it is treated.
The PS admitted that the pollution of Nairobi River, which drains into Athi River, has been a major challenge in the cleaning of the river.
"The sewerage system in Nairobi is overwhelmed due to population pressure. The available sewer system, which was installed in 1970s, serves only less than half of the capital city residents but the government has secured funding from Africa Development Bank to expand it to cover at least 80 per cent of the population", he said.
He singled out the cleaning of Nairobi River under the Nairobi Regeneration Programme among the interventions underway to eventually clean Athi River from the source.
"The mushrooming of factories in the Nairobi metropolitan, which empty their untreated waste into Nairobi River, has created a problem that needs a broad multi-agency approach to address" the PS explained, adding that the government will crack down on the unscrupulous polluters after the mapping.
He also called on county governments, especially Nairobi, Kiambu and Machakos, to play an active role in cleaning the river by vetting factories for environmental integrity before licensing.