Viable steps to restore Nairobi and Athi rivers

Monday August 19 2019

This image captured on July 19, 2019 displays the pollution of a section of Nairobi River passing through Dandora. Rehabilitating the river is doable. PHOTO | FILE | NATION MEDIA GROUP


Removing the poison that lurks in the deadly Nairobi-Athi-Galana-Sabaki River will be a tough call, but it is possible.

A few years back, Kenyans would walk down the river to draw drinking water, wash clothes, bathe or just swim, but today, our investigations show that trying any of these exercises would come at a great cost to their health.

Though filthy and dead inside, Nairobi is still not as bad as some of the world’s dirtiest rivers, which were reversed.

Environmental experts and international best practices show that it is cheaper to confront the problem head-on than continue on the path of half-hearted clean-ups downstream, when polluters are still emptying their wastes upstream.

Though it will be expensive, and would take a long time to achieve full results, it is not an insurmountable problem if lawbreakers are punished and the numerous agencies paid by the taxpayer to keep them safe do their job.



River Thames, which is billed today as one of the cleanest rivers that flows through a major city, was not always among the best rivers around the world.

More than 50 decades ago, the river that passes through London was so dirty that it was declared biologically dead.

At some point in its worst days, the stench coming from its waters was so bad that the British Parliament had to soak curtains in lime to stop the odour from cutting short their sessions.

Its turning point was the building of embankments that allowed for the building of riverside roads and walkways and concealed the huge sewerage pipes.

That was not all. Treatment plants would also be built to clean dirty water from the Thames before it was pumped into homes.

The same treatment plants also cleaned dirty water from homes before it went back into the river.


But, the biggest breakthrough came when sewage found a better use. Most of London's sewage sludge today is sold in pellet form as fertiliser for agricultural use.

“There is a phenomenal resiliency in the mechanisms of the earth. A river or lake is almost never dead. If you give it the slightest chance by stopping pollutants from going into it, then nature usually comes back,” Rene Dubos says in a paper published by the National Academy of Sciences.

According to the paper that surveyed the restoration of five rivers, as settlements expand in size and become more closely spaced, the wastes start to contain a larger percentage of persistent toxicants.

As a result, the ecological damage to the streams become more severe and the possibility of self-cleansing more limited.

Though not among the rivers that illustrate the power of restoration activities on a river, the Santa Cruz River in the US is a case study of how human activities and rapid urbanisation of the floodplain can bring about irreversible changes to a stream system.


Willamette River in northwestern Oregon is one of the rivers in the US that has been described as a success story.

The restoration of the river was mainly directed towards water quality restoration, protection of beneficial uses of the river water, and management of certain species of game fish.

“The restoration also includes reservoir management and research intended to reduce ecological disturbances in the river occasioned by changes in water temperature caused by the release of water from reservoirs,” the paper reads.

It is not just rivers that can be restored. It took over two decades of hard work before First Fulda Lake in Southern Minnesota was restored.

The immediate win was to stop farmers from draining their waste into the lake.

After this, the long-term job that took over 22 years before results started being seen involved draining as much of the lake as possible and then using a chemical called rotenone to kill the invasive fish. They also installed an electric barrier.


For Nairobi River, besides shutting down the polluters and moving more than 4,000 structures that have encroached on the riparian land, the country can consider building embankments and barriers to allow the river to flow free from contamination.

The other quick hit will be to force industries to treat their waste before disposing it into the rivers. Those without treatment capabilities should be shut down until they comply.

“We should look at bio-digesters and septic tanks as immediate solutions. The other important thing is to prioritise water and sanitation in the country,” Water and Sanitation Chief Administrative Secretary Winnie Guchu said.

She said the ministry has lined up urgent meetings with industries and polluters along the river in coming days to chart the way forward.

“This is not just about Kibera and the slums. The posh estates are also guilty. In Kileleshwa and Lavington, we have about 60 apartments disposing their waste directly into the river,” she said.


The National Environment Management Authority (Nema) has identified four main issues that must be dealt with to address the issue.

“Nairobi Water and Sewerage Company is overloaded and this is why people continue to drain raw sewage into rivers. We must also decisively deal with the informal settlements which are not sewered,” Nema acting director general Mamo Mamo said.

Mr Mamo said the other issues that must be fixed is solid waste management by the county governments, now that this is a devolved function, and the citizenry’s attitude towards the environment.

“We must deal with the throw-away culture. We generate waste but we expect someone else to pick it up. We must all take responsibility for the environment,” he said.

Makueni Governor Kivutha Kibwana says keeping the river clean is not just about the waterway but also about the country’s own survival.

Besides shutting down polluters, Prof Kibwana says those found to be polluting should be penalised heavily and funds collected used to clean the river.


He also says that some of the billions being sank into Thwake Dam should be channelled towards eliminating pollution.

His views are shared by his Machakos counterpart Alfred Mutua who says all polluters must be stopped.

Nairobi County’s environment executive Vesca Kangongo says that the county uses Sh1.7 billion annually to collect waste, adding that, alone, it cannot afford the costs of cleaning up the waste without the support of other agencies.

“It is a big assignment that requires a multi-agency approach. Nairobi County alone cannot afford the exercise since the river goes through several other counties,” Ms Kangongo said. She also raised the issue of behaviour change.

There is no estimate available on how much it will cost to complete the task but it will run into billions of shillings. But if Kenya fails to deal with the river today, then the country will pay a bigger price in another 10 years when the effects of the heavy-metal poisoning start to take effect.