Instead of following the natural topography, subdivisions in Los Angeles for the most part have been gridded right over streambeds. Thus, despite the elaborate flood control and drainage system that is now in place, stories of underground waterflows causing flooding, damage, or slippage under buildings are too numerous to include in this article.

Beginning excavations for Johnson Hall at Occidental College in 1912 unearthed a waterflow that "defied all efforts at control." The underground stream nearly jeopardized the realization of the orderly Mediterranean-inspired campus that was the brainchild of Myron Hunt. A similar incident recurred 46 years later, when excavation for Norris Hall of Science began.

An artesian flow beneath the GLAD edifice (built in 1927), on Norwalk Avenue was connected to a storm drain to prevent damage to the building. The builders must have supposed the tract names of adjacent blocks had been chosen purely for scenic value: "Artesian Heights" and "Artesian Heights Park."

For the creative and holistic-minded builder, however, a spring on ones' property could be turned into an asset. From the 20s until it was destroyed by a fire in 1941, the swimming pool of the Blankenship family, on the north hills above Live Oak View, was filled from "a very small spring and stream trickling down in a very small canyon above the pool."