Dam(n)

The Rio Salado riverbed has been dry for years where it runs through Tempe and Phoenix. At least it was until Tempe built big rubber dams at either end of a section about 11/2 miles long and let it fill to create Tempe Town Lake. They were right and the naysayers were hopelessly wrong: it did spur development. It's been such a success that when the Western dam burst a couple of years ago - apparently with a God-awful big bang , they replaced it with a new one and set about building a permanent version. The rubber dam is just visible under the artsy footbridge and the damn big hole will eventually disappear under the new dam.