Feb 20, 2014

Flip sides of same (water storage) coin

Are all dams the same?

Take for instance the curious case of the two Hoovers.

The above graph provides a comparison of surface water stage fluctuations in Florida's Lake Okeechobee and Arizona's Lake Mead.  Whereas Lake Mead has been in the news for its protracted now decade long drought, the news cycle flips between drought and flood mode for Lake Okeechobee on a year to year, even seasonal, basis.  The talk of last summer was estuary-damaging Lake releases caused by drenching summer rains, but the sub-par strength of its perimeter levee (and lowered regulation schedule) was also a big factor, too.

The deep canyons of the American West provide for a huge amount of storage capacity, but filling them is limited by a semi-arid climate which produces very little rain (less than 11 inches per year).  Compare that to tabletop flat south Florida that has prodigious amounts of rain (over 50 inches per year), but little in the way of topographic relief to store it long term.

The result for both is similar.


Excess Lake O water is released (i.e. wasted) to tide (see below) whereas dwindling levels in Lake Mead is pinching municipal obligations and power generating goals.  Lake O is perhaps unique in its ability to bounce from flood to drought mode schizophrenically in a half year's time.

In comparison it's been a continual decade-long drought for Lake Mead.


Each wishes for what the other has:

The West our rain and Florida their storage.

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