rjzimmerman:

This story tells us about some fanciful projects to divert water from the Mississippi River to locations in the west in order to relieve the drought. The story also tells us why that is impractical, including costs.

Excerpt from this story from Grist:

As western states grew over the twentieth century, the federal government helped them build several massive water diversion projects that would hydrate their growing urban populations: The Central Arizona Project aqueduct brought water from the Colorado River to Phoenix, for instance, and the Big Thompson system piped water across the Colorado Rockies to Denver. Each state along the Colorado River basin had the rights to a certain quantity of river water, divided among major users like farms and cities, and the projects were designed to help the states realize those abstract rights.

“States have [historically] been very successful in getting the federal government to pay for wasteful, unsustainable, large water projects,” said Denise Fort, a professor emerita at the University of New Mexico who has studied water infrastructure.

It’s easy to understand why politicians want to throw their weight behind similar present-day projects, Fort told Grist, but projects of this size just aren’t practical anymore. For one, there’s no longer enough unclaimed water to make most pipeline projects cost-effective. Additionally, building large infrastructure projects in general has become more difficult, in part thanks to reforms like the National Environmental Policy Act, which requires that detailed environmental impact statements be produced and evaluated for large new infrastructure projects.

These realities haven’t stopped the West’s would-be water barons from dreaming. The hypothetical Mississippi River pipeline, which gained new life last year amid devastating drought conditions, is a case in point. The basic idea is to take water from the Mississippi River, pump it a thousand miles west, and dump it into the overtaxed Colorado River, which provides water for millions of Arizona residents but has reached historically low levels as its reservoirs dry up. The Arizona state legislature allocated seed money toward a study of a thousand-mile pipeline that would do exactly this last year, and the state’s top water official says he’s spoken to officials in Kansas about participating in the project. Meanwhile, a rookie Democrat running for governor in California’s recall election last year proposed declaring a state of emergency in order to build a similar project.

The most obvious problem with this proposal is its mind-boggling cost. A federal report from a decade ago pegged an optimistic cost estimate for a similar pipeline at $14 billion and said the project would take 30 years to build; a Colorado rancher who championed the idea around the same time, meanwhile, estimated its costs at $23 billion. The actual costs to build such a pipeline today would likely be orders of magnitude higher, thanks to inflation and inevitable construction snags. Even at its cheapest, the project would cost about twice as much per acre-foot of water delivered than other solutions like water conservation and reuse.  

Even if the sticker price weren’t so prohibitive, there are other obstacles. The project would have to secure dozens of state and federal permits and clear an enormous federal environmental review; moving the water would also require the construction of several hundred megawatts of power generation. Plus, the federal report found the water would be of much lower quality than other western water sources.

Even if the government could clear these hurdles, the odds that Midwestern states would just let their water go are slim. A multi-state compact already prohibits any sale of water from the Great Lakes unless all bordering states agree to it, and it’s almost certain that Mississippi River states would pass laws restricting water diversions, or file lawsuits against western states, if the project went forward.