Saudi Arabias National Water Company is fast-tracking the Jeddah airport phase 2 sewage treatment plant (STP) as a public-private partnership (PPP) project.
The proposed STP will have a capacity of treating up to 500,000 cubic metres a day (cm/d).
A second wastewater project is expected to follow, near Taif.
Consultants are expecting a request for proposals for advisory work soon.
NWC originally tendered the project in 2012, then retendered it in 2015. It was delayed several times while the client reconsidered the size and procurement model for the scheme.
NWC prepared six assets for private sector investment in early 2016, but then went through a strategic review following the announcement of Saudi Arabias Vision 2030.
It previously tendered three urban water management concessions, in Riyadh, Jeddah, and Mecca and Taif.
NWC is now expected to push ahead with more privatisation plans.
This is seen as part of a broader move towards PPPs signalled in the 2016-20 National Transformation Programme.