Road construction work, especially bridge construction, may have impacts on the value and function of waters and wetlands. Construction projects over waterways frequently involve traffic detours or temporary construction access consisting of rip rap and culverts built into or completely across a stream. Because these methods discharge fill, they are subject to environmental permitting. An alternative construction practice is to use temporary bridging, such as floating or prefabricated bridging, or built-in-place structures.

Using current methods, state DOTs expend significant resources on environmental permitting and compensatory mitigation. If the use of temporary bridging is practicable in avoiding or minimizing impacts, there is an opportunity to protect the environment and reduce costs.

The objective of this study was to develop a guide for selecting and using temporary bridging for traffic detours or construction access, in order to avoid or minimize the environmental impacts of roadway construction over or adjacent to rivers, wetlands, and other waters of the United States.

The results have been published in Research Results Digest 330, and can be purchased or downloaded here.