scales. Recent discussions emphasised the role of secondary flow motion, considerations of fish dimensions in relation to the spectrum of turbulence scales, and the beneficial role of turbulent structures provided that fish are able to exploit them. The current literature on culvert fish passage focused mostly on fast-swimming fish species, but a few studies argued for better guidelines for small-bodied fish including juveniles. Finally, a solid understanding of turbulence typology is a basic requirement to any successful hydraulic structure design conducive of upstream fish passage. Minimum energy loss culverts In the coastal plains of Queensland, Australia, torrential rains during the wet season place a heavy demand on culverts. The natural slope of the flood plains is often very small, and little fall (or head loss) is permissible in the culverts. Researchers developed and patented the design procedure of minimum energy loss culverts which yield small afflux. A minimum energy loss culvert or waterway is a structure designed with the concept of minimum head loss. The flow in the approach channel is contracted through a streamlined inlet into the barrel where the channel width is minimum, and then it is expanded in a streamlined outlet before being finally released into the downstream natural channel. Both the inlet and the outlet must be streamlined to avoid significant form losses. The barrel invert is often lowered to increase the discharge capacity. The concept of minimum energy loss culverts was developed by a shire engineer in Victoria and a professor at the University of Queensland during the late 1960s. While a number of small-size structures were designed and built in Victoria, some major structures were designed, tested and built in south-east Queensland. Forestry In forestry, proper use of cross-drainage culverts can improve water quality while allowing forestry operations to continue. See also Notes References Oxford English Dictionary, Oxford English Dictionary, http://www.fhwa.dot.gov/engineering/hydraulics/pubs/11008/hif11008.pdf External links Impact of culverts on salmon Culvert fact sheet Culvert Analysis Bottomless Culvert Scour Study Culverts for Fish Passage Hydraulics of Minimum Energy Loss (MEL) Hydraulics engineering circular Culvert use, installation, and sizing Design guidelines for culverts Upstream fish passage in box culverts Bridges Tunnels