Scour Evaluation

Identifies the susceptibility of a bridge to scour and accurately records the present condition of bridge foundations and stream stability. The evaluation includes review of as-built foundation details; hydraulic studies, soundings, and other underwater investigations; knowledge of streambed and foundation soils; current condition of the foundation; streambed cross section profile measurement; stream flowrate measurements; and, similar historical and current data. A Level 1 Scour Evaluation results in the classification of each bridge as:

a. Scour Low Risk Bridge. Bridge with no history of scour problems and a low likelihood for scour problems in the future; or

b. Scour Critical Bridge. Bridge with an unstable foundation element, abutment or pier foundation due to observed or to assessed or calculated scour as determined from a Level I Feld Assessment or a Level 2 or 3 Scour Evaluation; or

c. Scour Susceptible Bridge. A bridge that based on a Level 1 Field Assessment is neither clearly scour critical or low risk. Further investigation is required to determine the status of the structure.