As I’ve mentioned before (and to remind that, despite my recent rant, I really do like a lot of David Zetland’s ideas!), the cost of coastal desalination represents one of the important boundary conditions on water supply in the western United States.

In that regard, Sandra Dibble reports this week on four proposals in various stages of the planning process to build desal plants in Mexico:

With scarce rainfall and increasing competition for water from the Colorado River, Baja California faces many of the same challenges as Southern California as it strives to meet the needs of a swelling population.

Now water managers are considering whether to build four desalination plants along the Pacific Ocean corridor that spans Rosarito Beach to Ensenada. Two of the proposals are binational ventures — one private, the other public — that would pipe a portion of the processed seawater to users in San Diego County.