By 1963, the downtown area had subsided as much as 3.4 feet. By 1986, it had sunk another 2.8 feet. Comparable subsidence of the Strip is 2.9 feet and North Las Vegas 5.0 feet. The greatest threat is posed by continued growth of earth fissures. These have been mapped and found to be correlated with preexisting Quaternary geologic faults.
Land subsidence is projected to continue as a function of ground water withdrawals.
In recent years net withdrawals have exceeded recharge by factors of 2 to 3. This can only be alleviated by reduced dependence on ground water which would increase reliance upon already over-allocated surface water. The built-up land data layer for Las Vegas provides a dramatic illustration of the spatial patterns and rates of change resulting from urban sprawl.