The Sea of Cortez Desalination Feasibility: Costs Double
The long-touted binational megaproject faces severe economic headwinds as updated estimates push the cost of delivered water to unprecedented highs.
For over a decade, policymakers have pointed south to the Sea of Cortez as the ultimate fail-safe for Arizona's water future. The proposal: build a massive desalination plant on the Mexican coast, pipe the freshwater 200 miles north, and pump it uphill into the state's distribution network.
But the latest feasibility report, drafted by the Binational Water Augmentation Committee, casts a long shadow over the project's viability.
The Escalating Price Tag
Previous estimates suggested the capital expenditure for the plant and pipeline would hover around $5 billion. The revised 2024 figures push that baseline to $11.2 billion, factoring in inflated material costs, the massive energy requirements for the uphill pumping stations, and right-of-way acquisitions through environmentally sensitive corridors.
| Water Source | Est. Cost per Acre-Foot (2024) |
|---|---|
| Colorado River (CAP) | $180 - $250 |
| Local Groundwater (Pumping Cost) | $50 - $120 |
| Proposed Desalination Delivery | $2,800 - $3,200 |
The Brine Disposal Problem
Reverse osmosis leaves behind highly concentrated brine. Environmental impact studies highlight severe risks to the sensitive ecology of the northern Gulf of California if brine is expelled directly back into the shallow, low-circulation waters.
Frequently Asked Questions
- Who would pay for this water?
- At $3,000 per acre-foot, agricultural use is economically impossible. The cost would have to be absorbed by high-margin industrial users (like semiconductor fabs) or spread across residential ratepayers via municipal surcharges.
- Is there a cheaper alternative?
- Yes. Advanced direct potable reuse (recycling wastewater back to drinking standards locally) costs roughly $1,200 per acre-foot and is currently gaining regulatory traction.