Bridges and other structures are often key features of a traffic free route. They are essential to cross rivers, canals and railways, and often necessary to cross heavily trafficked roads. Such structures will need to provide adequate width, parapet height, headroom, gradients and, where appropriate, separation from motor traffic. Continuity is essential to the popularity of any cycle route and when using existing structures a flexible pragmatic approach to headroom clearance and parapet height dimensions should be taken; the benefits of using an existing structure which allows a route to be opened should be clear. Sustrans has published guidance on parapet heights (pdf).
Excellent general guidance can be found in:
The Cycling England Design Guidance contains advice of several key detailed issues:
Other key references:
- Parapet Heights on Cycle Routes, Technical Information Note 30, Sustrans 2012 (pdf)
- Cycling Infrastructure Design, LTN 2/08, DfT 2008 (pdf) (Ch 10)
- National Cycle Network: Guidelines and Practical Details, Sustrans 1997 (Ch 5)
- Forestry Bridges, Forestry Commission
- Path Bridges, Paths for All, 2006 (pdf)
- Subways for Pedestrians and Cyclists Layout and Dimensions, TD36/93, Highways Agency (pdf)
- Design Criteria for Footbridges, BD 29/04, Highways Agency (pdf)