The relocation of 127,000 people encroaching on Nairobi River will cost about Sh1.8 billion, according to a report prepared by the national environmental agency.
The most affected areas are the slums of Kibera, Mathare and Kawangware, with more than 4,236 structures earmarked for demolition in an area estimated to cover about 60 square kilometres.
According to the National Environment Management Authority report, the Nairobi Rivers Rehabilitation and Restoration Programme, “... will be the most challenging and complex operation in the entire Sh12 billion three-year programme.”
This was evident two weeks ago when a move by the agency to evict informal traders around Globe Cinema roundabout and Kijabe Street turned violent, resulting in two people being shot by the police.
But the magnitude of the planned evictions is expected to rise dramatically when the Water, Environment and Lands ministries make good their threats to reclaim all wetlands and riparian land in the city, which, in some cases, could affect whole estates.
On the banks of Ngong River alone, a tributary of Nairobi River, Nema estimates that more than 6,800 people are living within the riparian area and will have to move.
Since last year Nema has been talking to families and businesspeople living near the rivers to convince them to leave peacefully. But there have been indications in the last few days that most will not go without a fight.
The government must be prepared to receive a flood of court injunctions which could cripple its efforts to reclaim wetlands or rehabilitate Nairobi River.
The Globe Cinema roundabout protesters claimed to have secured a court order stopping the evictions.
The government has identified 500 acres in Njiru, on the outskirts of the city, according to sources familiar with a Cabinet memo approved by the government.
Those moved will be given 30 by 50 foot plots on a 33-year lease. The houses will be approved by the City Council.
Although the owner of the land had asked for Sh580,000 per acre, the commissioner of Lands was surveying the area to authenticate its value.
In an earlier interview, Nema director-general Muusya Mwinzi said evictions would be done humanely. But only those who have genuine title deeds would be considered for compensation.
Most of the people who live on the river banks or landlords who own the houses only have allotment letters.
They should not have been given the letters in the first place because such riparian land belongs to the government.
Those targeted are houses and business premises within the 30-metre riparian region on either side of the rivers. They include Jua Kali garages, car wash sites, markets, timber yards and agriculture plots.
In October, Nema had to shelve a plan to have the City Council issue quit notices to garage owners around the Globe Cinema area.
They feared that involving the council would result in forceful eviction, making the rehabilitation programme unpopular with the public.
The rehabilitation programme covers Ngong, Nairobi and Mathare rivers.