DEWA and Acwa Sign Hassyan Shareholder Deal for a Planned 240 MIGD Dubai Seawater Plant
Dubai Electricity and Water Authority (DEWA) and Acwa have signed a shareholder agreement for Hassyan’s second phase, which will take the seawater plant to 240 million imperial gallons a day.
For Dubai, the new phase of 60 million imperial gallons a day (MIGD) completes the expansion DEWA has laid out for its water system. DEWA says capacity reaches an estimated 735 MIGD once both phases are complete; on The Edge’s arithmetic, this phase and the 120 MIGD DEWA expects to add this year together close the gap from June’s base.
In The Edge’s reading, the larger change is in technology, with membrane plants set to supply more than two fifths of Dubai’s desalination capacity, against under a quarter in June.
A shareholder agreement joins the 30-year water contract
Saeed Mohammed Al Tayer, Managing Director and CEO of DEWA, and Mohammad Abunayyan, Founder and Chairman of Acwa, signed the two agreements, DEWA said in a press release filed on the Dubai Financial Market on Friday 6 November. The release values them at AED 1.76 billion, an estimated $478 million in its own conversion.
A project company will develop, finance, build and operate the plant. DEWA owns 60% of it and Acwa 40%. Under the 30-year water purchase agreement, the second phase will have an estimated production capacity of 60 MIGD, the release said, which it gives as 272,000 cubic metres.
The water purchase agreement and its main terms were set out earlier. Acwa told the Saudi Exchange it signed the agreement for the Hassyan seawater desalination project on 28 October, and DEWA confirmed the shareholdings, the 30-year term, the capacity in cubic metres and the contract value in a letter to the Dubai Financial Market the next day.
That letter also gave October 2029 as the expected commercial operation date.
Friday’s release adds the shareholder agreement and shows that the 272,000 cubic metre project is the second phase of the Hassyan plant. It also gives the value in dirhams and the capacity in gallons.
Hassyan seawater reverse osmosis, phase two
| Term | Detail |
|---|---|
| Agreements | Water purchase; shareholder |
| Value | AED 1.76bn ($478m est.) |
| Term | 30 years |
| Capacity | 60 MIGD est. |
| Cubic metres a day | 272,000 |
| DEWA stake | 60% |
| Acwa stake | 40% |
| Commercial operation | October 2029 (expected) |
Value, capacity, stakes and term from the 6 November 2026 release; “est.” marks the release’s own approximations. The commercial operation date is from DEWA’s exchange letter of 29 October 2026.
Hassyan is set to reach 240 MIGD, which DEWA calls the world’s largest SWRO plant
The second phase builds on a first phase of 180 MIGD, which the release says was developed with an investment of AED 3.357 billion as DEWA’s first project under the independent water producer model. DEWA’s Hassyan project page, last updated on 28 October, gives AED 3.377 billion for the same phase.
The release gives no comparable investment figure for phase two, whose AED 1.76 billion is the value of the two agreements.
Together the phases come to 240 MIGD. The new phase adds a third to the first phase and makes up a quarter of the finished plant. Al Tayer said the addition will make Hassyan “the world’s largest SWRO desalination plant”, the claim behind the release’s headline.
At 30 June, DEWA’s capacity table listed Hassyan’s Block A at 60 MIGD, commissioned in the first half. DEWA said in its half-year results that it expected to add a further 120 MIGD of reverse osmosis capacity during 2026, without naming the plant. That figure equals the gap between the 180 MIGD first phase and Block A.
Dubai’s desalination capacity is set to reach 735 MIGD
DEWA’s installed desalination capacity stood at 555 MIGD on 30 June, the latest figure in its results; it has not yet reported the third quarter. The 120 MIGD expected this year and the 60 MIGD of the new phase add up to 180 MIGD. That is exactly the gap between June’s installed base and the 735 MIGD plan.
DEWA desalination capacity (in MIGD)
| Plant | 30 June 2026 | Planned |
|---|---|---|
| Jebel Ali, multi-stage flash | 427 | 427 |
| Jebel Ali, reverse osmosis | 63 | 63 |
| Palm Jumeirah, reverse osmosis | 5 | 5 |
| Hassyan, reverse osmosis | 60 | 240 |
| Total | 555 | 735 |
30 June figures from the first-half 2026 results release of 12 August 2026; the Hassyan and total planned figures are from the releases of 6 November and 12 August 2026. The planned split by plant is The Edge’s, assuming the other plants are unchanged; it reproduces the planned 308 MIGD of reverse osmosis capacity in the half-year release.
On those figures, capacity rises by 32.4% from the end of June. Reverse osmosis accounted for 23% of the total at 30 June, the half-year release said. The 308 MIGD planned for it would be 41.9% of the total.
Hassyan would supply 32.7% of the emirate’s planned capacity and 77.9% of its reverse osmosis capacity. Jebel Ali’s reverse osmosis units, at 63 MIGD, would be a little over a quarter of Hassyan’s finished size.
The older thermal technology keeps its volume but loses share. Jebel Ali’s multi-stage flash plant, at 427 MIGD, made up 76.9% of capacity in June. Unchanged, it would make up 58.1% of the planned total.
The plan is meeting rising use. DEWA produced 40.25 billion imperial gallons of desalinated water in the second quarter, an average of 442.3 MIGD. That average equals 79.7% of the capacity installed at the end of June, a comparison of The Edge’s rather than a utilisation figure from DEWA. Its customer accounts reached 1.36 million by 30 June, up 5.63% in a year.
The timetable is stated two ways. Friday’s release says capacity will reach an estimated 735 MIGD by 2029, once both Hassyan phases are complete. The half-year release in August gave the end of 2030 for the same 735 MIGD, so the newer release gives the earlier date of the two. The half-year release added that 308 MIGD of that total would come from reverse osmosis powered by renewable energy.
The release ties the project to the UAE Water Security Strategy 2036 and the Dubai Clean Energy Strategy 2050. Al Tayer said the aim was a water system that keeps pace with Dubai’s growth and its rising demand for water services.
Hassyan is a small part of Acwa’s water portfolio
For Acwa, which calls itself the world’s largest private water desalination company, the phase is small against its base. Its portfolio had 9.7 million cubic metres a day of desalination capacity at 30 September, its nine-month results release said. The new phase’s 272,000 cubic metres equal 2.8% of that, the same share set out earlier against its June figure.
Agreements signed in Acwa’s first nine months added 0.6 million cubic metres a day of water capacity to its development pipeline; the Hassyan water purchase agreement, signed on 28 October, came after that period. The company’s third-quarter results were set out earlier.
Abunayyan described a partnership with DEWA built over more than a decade in Dubai’s power and water sectors. He called the Hassyan expansion a natural next step in that partnership, one that lets Acwa build on its existing investment and development capabilities.
What to watch:
End of 2026: DEWA’s expected addition of 120 MIGD of reverse osmosis capacity during the year, as stated in its half-year results.
October 2029: expected commercial operation of the second phase, per DEWA’s 29 October exchange letter.
Figures are from DEWA’s press release filed on the Dubai Financial Market on 6 November 2026, its letter to the Dubai Financial Market of 29 October 2026, its first-half 2026 results release of 12 August 2026 and its Hassyan project page (last updated 28 October 2026), and from Acwa’s Saudi Exchange disclosure of 28 October 2026 and its nine-month 2026 results release of 5 November 2026; percentages, shares and averages not attributed to a source are The Edge’s calculations.
Sources: Dubai Electricity and Water Authority, Dubai Financial Market, Acwa, Saudi Exchange, The Edge.
