Table 1 - Matching preferred crossing type to waterway type
Characteristics of Waterway Type
Recommended Crossing Type
Major permanently or intermittently flowing waterway (e.g. river or major creek), habitat of a threatened fish species.
Bridge, arch structure or tunnel.
Named permanent or intermittent stream, creek or waterway with clearly defined bed and banks with semi - permanent to permanent waters in pools or in connected wetland areas. Marine or freshwater aquatic vegetation is present. Known fish habitat and/or fish observed inhabiting the area.
Bridge, arch structure, culvert  or ford.
Named or unnamed waterway with intermittent flow and potential refuge, breeding or feeding areas for some aquatic fauna (e.g. fish, yabbies). Semi - permanent pools form within the waterway or adjacent wetlands after a rain event. Otherwise, any minor waterway that interconnects with wetlands or recognised aquatic habitats.
Culvert  or ford.
Named or unnamed waterway with intermittent flow following rain events only, little or no defined drainage channel, little or no flow or free standing water or pools after rain events (e.g. dry gullies or shallow floodplain depressions with no permanent aquatic flora present).
Culvert , causeway or ford.
Class 1 Major fish habitat
Moderate fish habitat
Minimal fish habitat
Unlikely fish habitat
 In all cases bridges are preferred to arch structures, culverts, fords and causeways (in that order).
 High priority given to the "High Flow Design" procedures presented for the design of these culverts - refer to Design Considerations section of this document, or engineering guidelines (Witheridge, 2002).
 Minimum culvert design using the "Low Flow Design" procedures; however, "High Flow Design" and "Medium Flow Design" should be given priority where affordable (refer to Witheridge (2002)).
 Fish friendly waterway crossing designs possibly unwarranted. Fish passage requirements should be confirmed with the local fisheries department/authority.
The following sections provide a brief overview of the design considerations for "fish friendly" waterway crossings within Australia. Detailed engineering guidelines, including terrestrial fauna requirements, are provided in Witheridge (2002).
BRIDGES AND ARCH STRUCTURES
Avoid locating bridge piers or foundations within the main waterway channel.
Design and orientate bridge piers, including those located within overbank areas, to avoid the formation of large-scale turbulence or the erosion of the bed and banks of the waterway.
fish passage requirements for waterways crossings