Simple hydraulics of open channel water flow is usesd to fine the water level response to earth tilt along the 200 km long Los Angeles Aqueduct. The water level changes are shown to depend on the length scale of the tilt field. Tilts over lengths greater than 10 km permit the water to assume an essentially equilibrium level throughout the tilt field; change in water depth is therefore directly proportional to the degree of slope change. Tilts occurring on length scales shorter than 10 km require the use of an integral relation between tilt and water depth. The relation is used to model a tilt field corresponding to an anomalous water level event observed on the Los Angeles Aqueduct.