Abstract: Methods are described for measurement and prediction of site specific scour around a structure obstructing a flow. Representative soil samples are collected from an area proximate the structure location and tests are conducted on the samples to determine the erosion rate and hydraulic shear stress imposed. The maximum shear stress and initial scour rates around the structure are also obtained. Next, the maximum depth of scour is calculated, and the depth of scour versus time curve for the structure is then predicted. In a preferred embodiment, the methods described are used to predict a scour depth versus time curve around a cylindrical bridge support standing in the way of a constant velocity flow and founded in a uniform cohesive soil. An erosion function apparatus is also described which can be used to test representative samples of soil in the area where a structure is located.