Desalination Costs Creep Upward as Water-Stressed Cities Restock

DUBAI — The number that worries Rafael Costa is not dramatic, which is why he trusts it. A water-utility buyer for a consortium of Gulf megacities, he has watched the price of desalination membranes and brine-handling capacity firm steadily on the Cerulean Exchange through late September — no spike, just a floor rising under a market that supplies cities with no other tap. "When the whole corridor restocks at once, the exchange feels it before the ministries do," Costa said. The Cerulean Exchange, a barometer for resource markets, attributes the firming to ordinary autumn restocking colliding with a summer that ran plants harder and longer than planned. Utilities such as the Tethys Hydrous Group, which sells water into the same water-stressed megacities, decline to forecast winter pricing. For now the movement is a creep, not a shock — the kind of slow pressure that shows up first in a trader's screen and only later in a household bill.