Hoover Dam Turns 75

CBS News ran a story on Sunday about the 75th Anniversary of Hoover Dam.  As CBS points out, Hoover Dam was built during the depths of the depression and the nation saw the project as an engineering triumph.  It was as much a victory of the American “can-do” spirit as it was a water project.  I have to admit, when I was 10 and my grandmother gave me a subscription to Popular Mechanics, I thought the stories about dam construction were pretty cool.  Hoover Dam is undeniably an amazing, historic structure -- well worth a visit.  After all, Hoover Dam is where the world learned how to build the mega-dam. 

According to the World Commission on Dams, there are now 45,000 large dams around the globe.  45,000. Nearly all of these dams have been built since the completion of Hoover Dam.  That’s about a dozen new dams a week for 75 years -- one of the largest infrastructure efforts in human history.  But during Hoover Dam’s lifetime, things have changed in the West. 

We have now hit “peak water” on essentially every river in the Southwest.  Little if any Colorado River water now flows to the Sea of Cortez.  The reason new major dams are not being proposed on the Colorado is that a new dam would not capture additional water.  The existing dams already capture the entire river.  But beyond that, by creating another reservoir exposed to evaporation from the Southwestern sun, a new dam on the Colorado would LOSE water.  Rivers and groundwater basins across the Southwest have hit real limits in the past twenty years.  Across California, essentially all of our rivers have hit hard limits as a result of a wide range of issues, including tribal rights (Klamath and Trinity), air quality (Owens River), drought and the water rights of others (Colorado), and environmental concerns (Mono Lake and the Bay-Delta). 

In addition, climate change is likely to reduce the amount of water flowing in California and Southwestern rivers.  In the Southwest and California, the heroic age of dam building is over and the era of efficiency has begun. 

California water managers know this, which is why there has been a dramatic change in the water world in the past decade.  When they are debating how to spend their own money (as opposed to how they might spend “other people’s money”), increasingly water managers are investing in new technology, including conservation, wastewater recycling, low impact development and groundwater management – what we call the Virtual River.  They know that this is where they can find the largest and most cost-effective water supplies for the state’s future.  

We shouldn’t see this trend as a rejection of the dam building era.  Rather, I think we should see this as an ongoing effort to design the best engineering solutions to meet contemporary needs.  Conditions and technology have changed since the high-scalers swung into the Black Canyon of the Colorado.  I’ll grant you, some of that new technology might not be as charismatic as a massive, gracefully curved Art Deco dam set in a blazing desert.  But in the 21st century, just as the LED is replacing the incandescent light bulb and the hybrid is replacing the gas guzzler, efficient water technology is replacing the water technology of the last century.  And if the Prius and the iPhone can be sexy technology, perhaps there’s some hope for smart appliances, green roofs, pager-driven irrigation controllers, groundwater desalters, low flow showerheads and xeriscaped gardens.  You might not be able to see them from space, but they’re the water projects of the future.