Mombasa Private Desalination Plant

Private Desalination Investment (water security), Mombasa
Project
Status	proposed
Theme	Water
Pillar	Infrastructure
Counties	Mombasa
Lead organisation	Economic Development and Investment Council for Greater Mombasa
Partners	Possible partners: County Government of Mombasa, Mombasa Water Supply and Sanitation Company
Funding source	Private finance sought, with a water purchase agreement; no structure agreed
Website	https://edicpwani.ke/#OurPriorities

The Mombasa Private Desalination Plant is a project within the Water theme. It is a proposal by the Economic Development and Investment Council for Greater Mombasa (EDIC) for a privately financed seawater desalination plant to add to the water supply of Mombasa County, which has no fresh water source of its own and receives well under half of what it needs. Desalination has been promised in Mombasa since 2013: a KSh 16 billion award to two European firms in 2018 never reached construction, a county water company procured a new feasibility study in 2024, and the governor said in 2025 that a county advertisement for a plant drew no acceptable responses. EDIC now aims to make a plant bankable by testing off-take structures and sounding out investors. A separate page covers the Pwani 2050 idea of a network of small solar desalination plants.

What it is

EDIC describes "privately financed desalination to augment industrial and municipal supply, improving reliability for growth sectors", and says it "will prepare the concept, test off-take structures, align with regulators, and sound out investors to advance a bankable transaction". It names no site, capacity or cost.

The county's water company, the Mombasa Water Supply and Sanitation Company (MOWASSCO), sought consultants in 2024 for a feasibility study of seawater desalination at two identified sites. Its clarification to bidders shows the study was to cover a design, build, own, operate and transfer model, water purchase agreements and a financial model, over 12 months; a bidder warned that "bankability is critical" and that financiers would require national government alignment. MOWASSCO replied that desalination "is an idea which has been courted for ages through the Ministry of Water and the National Government as Mombasa County have never had its own source of water". The county's development plan for 2026/27 records KSh 120 million planned and KSh 70 million approved for a "Water Desalination Plant" in 2025/26.

The water gap

Mombasa draws its water from Mzima Springs in Taita-Taveta, Baricho in Kilifi, and Marere Springs and the Tiwi boreholes in Kwale, and shares these with other towns. Estimates of demand and supply vary, but every source puts demand at about 150,000 to 200,000 m³ a day against a supply of 20,000 to 55,000 m³. In August 2025 Governor Abdulswamad Sharif Nassir said the county received about 40,000 m³ a day but lost about 60 per cent of it, so only about 20,000 m³ reached residents. The water regulator's targets for MOWASSCO for 2023 to 2026 were 10 to 12 hours of supply a day and non-revenue water falling from 45 to 39 per cent; its approved tariffs run from KSh 150 to 250 per m³ for households and KSh 182 to 255 per m³ for commercial and industrial users. Residents who buy from handcart vendors pay KSh 30 to 40 for 20 litres, which is KSh 1,500 to 2,000 per m³.

Rationale

The case rests on the structural deficit and on Mombasa having no source of its own. National planners have long expected desalination to be part of the answer: the National Water Master Plan 2030, prepared with JICA in 2013, says "a desalination plant is necessary for Mombasa and coastal area" and allows for 93 million m³ a year of desalinated water for Mombasa. Governor Nassir campaigned on a seawater plant, and the county plan for 2023 to 2027 commits to "operationalize a sea water desalinization plant to offer residents an alternative source of potable water". In July 2025 he said a county feasibility study had found desalination feasible, with water costing "slightly higher than it is now" but less than vendors charge. EDIC adds an industrial argument: reliable water for growth sectors.

Status and timeline

In December 2013 Governor Hassan Joho signed a memorandum with Toyota Tsusho for a feasibility study of a 100,000 m³ a day plant; it lapsed. In December 2018 the county awarded Almar Water Solutions of Spain a 100,000 m³ a day plant in the North Mainland, to be financed, built and run for 25 years before transfer to the county, and Aqua Swiss a 30,000 m³ a day plant in Likoni, at a combined KSh 16 billion. In May 2021 MOWASSCO's managing director said the plants had been stuck for four years "because of lack of letter of comfort" from the national government. The county's own plan records that the project "failed to take off due to lack of a guarantee from the National Government as a result of the coming up of the Mwache Dam project".

MOWASSCO's feasibility study procurement followed in mid-2024. In August 2025 Governor Nassir said: "we also tried to advertise for a desalination plant but we did not receive positive responses". No Mombasa desalination project appears in the PPP Directorate's status report of June 2026; the only desalination project in the national pipeline is in Lamu, where negotiations with Rasli Bahari Kenya were under way for a 120,000 m³ a day plant.

How the project is being procured

No Terms of Reference for a plant, request for proposals or PPP listing has been published. The 2024 MOWASSCO document is for a feasibility study only. The structure envisaged, a private plant selling water under a long-term purchase agreement, would need either a creditworthy buyer or a government guarantee, which is what the 2018 deal lacked.

Who is involved

EDIC is a multi-stakeholder council for Greater Mombasa chaired by Dr Kevit Desai. The County Government of Mombasa and MOWASSCO would be the buyer and distributor of the water, and the Coast Water Works Development Agency supplies bulk water to the county. The Water Services Regulatory Board sets tariffs. No investor or operator has been named.

• Economic Development and Investment Council for Greater Mombasa
• Mombasa Water Supply and Sanitation Company

Concerns and counterpoints

No one has commented in public on EDIC's proposal itself. The doubts below come from Mombasa's own record and from experience elsewhere.

Competing supply

The national guarantee for the 2018 plants was withheld because of the Mwache Dam. The dam's main structure was completed in August 2026, and it is designed to supply about 186,000 m³ a day to Mombasa and Kwale. Two national PPPs also aim at the coast's deficit: the Sabaki Water Carrier and the Mzima II pipeline of 105,000 m³ a day. A private plant paid for its full capacity would compete with these sources as they arrive, and the buyer could end up paying for water it does not need.

Water losses

Mombasa loses about 60 per cent of the water it receives, which the governor put at about KSh 100 million a month. On the governor's figures, the water lost each day is of the same order as the output of a medium-sized desalination plant, and the county is buying smart meters to reduce it.

Cost and affordability

Water expert Abdalah Mbwana says desalination "sourcing and production costs are astronomical" and power tariffs "highly prohibitive" on the coast. At a coast governors' water meeting, a governor was reported as saying desalination was not viable because of high power bills, and the governors backed bringing private operators into bulk water supply instead. The county plan itself promises that "there shall be no exploitation of residents in the pricing of water". Someone, whether customers, the county or the national government, would have to cover the gap between the cost of desalinated water and the regulated tariff.

Off-take risk

Ghana's Teshie-Nungua plant near Accra, built under a similar long-term water purchase agreement, stands idle; an international tribunal ordered Ghana Water to pay US$235 million after the agreement was terminated, almost twice the plant's build cost, and the state is liable under its guarantee. MOWASSCO's own study brief proposed the same contractual shape.

Marine environment

Seawater desalination returns concentrated brine to the sea. No environmental study of brine discharge off Mombasa has been published, and the governor has said that 95 per cent of Mombasa's liquid waste already goes into the ocean, so the near-shore waters near the Mombasa Marine Park are already under stress.

Sources

• MOWASSCO desalination feasibility study RFP clarification, 2024.
• MOWASSCO approved tariff 2023/24 to 2025/26, WASREB, 2023.
• Kenya PPP Projects Progress and Status Report, June 2026, PPP Directorate.
• Mombasa County Integrated Development Plan 2023-2027.
• Mombasa County Annual Development Plan 2026/2027.
• National Water Master Plan 2030, Athi Catchment Area, JICA, 2013.
• WASREB Impact Report 18 (2024/25), WASREB, 2026 (16 MB, linked rather than uploaded).