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Wednesday, February 13, 2013

Is this the book that started the cement river?

I was talking with Nicole Salem from the City of Chula Vista this morning. She told me that the textbook by Ven Te Chow, from the 1950s, is the groundbreaker (excuse the pun) theory source for channeling rivers into cement sluices.

I immediately ordered "Open-Channel Hydraulics" from my local library and look forward to reading it. The text itself is supposed to be a model for clarity and teaching complex principles, so that will be of interest.

But more-so will be why Chow thought that cementing in our riverways was the way to go.

Have any of you background in this, read this book or have comments? I'd love to learn from you!

1 comment:

  1. Chow was an Engineer so put yourself in the Engineer's mind set of the time; The Problem-we need to convey as much water as we can as fast as possible; the science-concrete has Manning roughness n=0.015 significantly less than the manning roughness for a natural channel (n=0.035 typical); Solution-line your channel with concrete for maximum conveyance. Back then, there was one problem and one easy solution. Now-a-days we have many problems and many environmental factors to consider such as ground water depletion, flora and fauna. When Chow wrote his book in the 1950s, there was no EPA and no conservation advocacy groups, so engineers became tunnel-vision-ed. We did not see the whole picture until recently. Now engineering is finding new innovative and sustainable ways of conveying storm water where we are not depleting ground water reserves and we are having a minimal effect on the local ecosystem. I am a Student of Environmental Engineering at SDSU and if you are more interested in Open Channel Hydraulics I suggest you take a look at SDSU Professor V. M. Ponce’s website (ponce.sdsu.edu) very great resource for the history of hydraulics and lots of video case studies. Enjoy!

    -Nicole Marie