CORPUS CHRISTI, Texas—Five years ago, when ExxonMobil came calling, city officials eagerly signed over a large portion of their water supply so the oil giant could build a $10 billion plant to make plastics out of methane gas.Yet the desalination plans remained years away from completion, hung up on questions from state and federal environmental regulators—the Texas Commission on Environmental Quality and the US Environmental Protection Agency—over the ecological consequences of dumping hundreds of millions of gallons of salty brine per day into Corpus Christi Bay.We have to have this permit.”Today the pursuit of desalination has become an increasingly desperate race to meet incoming demands.Regulators and scientists worry that each plant’s discharge of tens of millions of gallons of hyper-salty wastewater per day could disrupt major reproductive cycles for a host of aquatic species, which rely on the half-salty waters of the coastal bays for larvae to mature.All together, environmentalists say, the five plants’ discharge, coupled with the water pollution and ocean freighter traffic from the industrial boom they would unleash, may constitute a near-fatal blow for life in the bay, whose once-teeming ecosystems have nursed communities on its banks since long before Corpus Christi."