Cleanup and rehabilitation work along the Nairobi River moved into a higher gear in August 2026, with sewer separation, dredging, and wastewater treatment plant expansion underway at multiple sites from Globe Roundabout downstream to Dandora and the Kariobangi wastewater treatment plant, according to a report published 18 August 2026 by People Daily.
Key takeaways
- A 27-kilometre twin trunk sewer is being installed at Baba Dogo, with a pedestrian bridge already completed, People Daily.
- At Globe Roundabout, the river flow is being separated from sewage, alongside drainage works and preparation of a proposed public recreation area, People Daily.
- The Dandora works include excavated sewer trenches, expanded wastewater treatment infrastructure, and pollution control around the Dandora dumpsite, People Daily.
- The Kariobangi wastewater treatment plant is being expanded to improve downstream wastewater management, People Daily.
- Thousands of young people in settlements along the corridor have been engaged through the ClimateWorX Mtaani Initiative on waste collection and environmental restoration, People Daily.
What happened along the corridor
Principal Secretary for Internal Security and National Administration Raymond Omollo outlined the package of works on 18 August 2026, grouping them under the Nairobi River Basin Regeneration Programme, People Daily. The report describes simultaneous activity at Globe Roundabout (river sewage separation, drainage, and a proposed recreation area), Baba Dogo (a 27-kilometre twin trunk sewer installation plus a completed pedestrian bridge), Lucky Summer (river widening, dredging, and gabion reinforcement of the banks), and Ngomongo (solid waste clearance and restored drainage channels), People Daily.
At Dandora, the scope narrows to wastewater engineering: sewer trenches are being excavated, treatment infrastructure is being expanded, and pollution around the Dandora dumpsite is being targeted, People Daily. Upstream at Gikomba, riverbank clearing and levelling are underway, and at Kamukunji riparian encroachments have been removed alongside a completed community centre, sports field, and spectator facilities, People Daily. The Kariobangi wastewater treatment plant is also being expanded, the report states, in a move explicitly aimed at improving downstream wastewater management, People Daily.
Omollo framed the works as a single, distributed intervention rather than a single-site project, writing: "The work stretches across the river corridor, with different interventions advancing simultaneously," People Daily. He added that the programme is "restoring the river system into a cleaner, safer and greener public asset while renewing the urban spaces and communities along its banks," People Daily. The report does not give contract values, completion dates, or a treatment capacity in million litres per day for either the Kariobangi expansion or the new Dandora works.
Specification read
For a buyer, the headline numbers to extract are the 27-kilometre twin trunk sewer at Baba Dogo and the parallel expansions at the Dandora and Kariobangi plants, reported in People Daily. Converting the trunk sewer: 27 km of DN-class pipe laid in a dense urban corridor is typically sized to carry a peak dry-weather flow in the order of 100,000–300,000 m³/day once a full catchment is connected (general industry range, not from the sources); a 27 km run also implies a programme-level pipe, manhole, and interceptor chamber package rather than a single skid. At the plant end, both Dandora and Kariobangi sit in the mid-to-large Municipal class, where a typical treatment train runs screening → grit removal → primary clarification → biological treatment (often an A2O, MBBR, or SBR configuration in East African plants of this scale) → secondary clarification → tertiary filtration and disinfection. The reported scope here — sewer trenches, expansion of treatment infrastructure, and the river-flow separation at Globe Roundabout — bears on the front of the train: conveyance, preliminary treatment, and primary/solids handling, not yet on tertiary polishing. Where plants of this size still struggle with floatables, oils, and sloughed biosolids carryover, suppliers are commonly asked to compare a DAF vs Clarifier step or a packaged Integrated Sewage Treatment line ahead of the biological stage.
Recognition sentence: if your plant is a mid-to-large Municipal works in the 50,000–250,000 m³/day range with raw BOD in the 200–400 mg/L band (general industry range, not from the sources), is currently load-shedding or bypassing during storm events, and is under regulator or public pressure to cut river discharge loads, the Kariobangi and Dandora expansions are the local reference points to benchmark scope, sequencing, and the share of budget going to trunk-sewer separation versus in-plant capacity.
FAQ
What exactly is being built at Dandora?
Excavated sewer trenches, expanded wastewater treatment infrastructure, and pollution control around the Dandora dumpsite, according to People Daily. No capacity in m³/day, contractor name, or contract value is given in the source.
How big is the Kariobangi expansion?
The report confirms expansion is underway at the Kariobangi wastewater treatment plant to improve downstream wastewater management, People Daily. The source does not state the additional flow in m³/day or the population equivalent served; for comparable East African municipal upgrades, an expansion of this class typically adds tens of thousands of m³/day of design capacity (general industry range, not from the sources).
What is the 27 km trunk sewer at Baba Dogo?
It is described as a 27-kilometre twin trunk sewer under installation at Baba Dogo, part of the Nairobi River Basin Regeneration Programme, with a pedestrian bridge already completed, People Daily. The report does not give pipe diameter, material, lead time, or award value.
Where do ClimateWorX Mtaani workers fit into the procurement picture?
They are engaged on waste collection, environmental restoration, and rehabilitation in settlements along the river corridor, People Daily. The source does not state contract value, scope duration, or how the labour component relates to the equipment supply chain.
