Abutments

Road bridge abutments can be half the cost of a road bridge when the span is about 10m so the choice is important. Forestry bridges are generally high in the catchment area so the flows are limited. This means that abutment heights are generally below 3m. This makes concrete economic and easy to construct. It is not the most environmental solution as they look urban and result in high carbon dioxide generation. For these reasons gabion abutments are sometimes used. More recently some reinforced earth abutments have been built using moraine from the surrounding hills. This is economic for high wind farm abutments.

Footbridge abutments are much lower cost and can be concrete but are better as gabion, bank seat or reinforced earth. If concrete is the choice pipes are often used as permanent shutters and filled with concrete. In areas of high environmental value timber piles are a good solution but need need special design considerations.