Shouldn't the headline be more like green ($) is the new green?

Perhaps it’s a sign of how dire the drought has gotten in California: Water-saving projects long on the drawing board, despite being cheap and easy, are finally coming to campuses. Last month at the University of California at Davis, workers rerouted recycled sewer water to the chiller plant, which supplies air conditioning. The project will save 61 million gallons annually, or almost 10 percent of the campus’s potable-water supply.

The investment? $20,000 in materials and two weeks of staff time.

"We never really did it because our water was relatively inexpensive, so there was never a need to make better use of it," says David Phillips, director of utilities. "The drought was the prompt for us."

via chronicle.com

If the value of a gallon of water is $0.01 (one penny) then the annual benefits are $610 thousand. Let's say the staff is 25 workers making $100 an hour. The cost of two weeks of staff time is then about $200 thousand. And let's assume that rerouting only works for a single year. 

Even with these ridiculous assumptions the net benefits are $390,000 and benefit-cost ratio is almost 3 to 1. 

What sort of inertia causes one to ignore a water-saving project like this one?

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  1. David Zetland Avatar

    Classic OPM: Workers aren’t going to spend their time to save Other People’s Money!

  2. John Whitehead Avatar

    But don’t most universities have sustainability types who should be looking for this sort of savings?

  3. Danny Brent Avatar

    The average cost of water in Davis is less than $0.004 (http://cityofdavis.org/city-hall/public-works/water/water-rates). With your assumptions that would lead to a benefit-cost ratio of 1.2. If this is an annual gain that’s realized for several years it’s probably still a really good investment. The key is in the director’s quote; water is still too cheap to justify a lot of investment in efficiency (or even thinking about those investments). My guess is that without the public/social pressure of the drought for a public institution this still would not have been done.

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