Culvert

Dry culverts are used to channel a fire hose beneath a noise barrier for the ease of firefighting along a highway without the need or danger of placing hydrants along the roadway itself.

The culvert type and shape selection is based on a number of factors including requirements for hydraulic performance, limitations on upstream water surface elevation, and roadway embankment height.

[3] Culverts can be constructed of a variety of materials including cast-in-place or precast concrete (reinforced or non-reinforced), galvanized steel, aluminum, or plastic (typically high-density polyethylene).

Many US agencies such as the Federal Highway Administration, Bureau of Land Management,[5] and Environmental Protection Agency,[6] as well as state or local authorities,[4] require that culverts be designed and engineered to meet specific federal, state, or local regulations and guidelines to ensure proper function and to protect against culvert failures.

Ongoing culvert function without failure depends on proper design and engineering considerations being given to load, hydraulic flow, surrounding soil analysis, backfill and bedding compaction, and erosion protection.

[7][2] For existing culverts which have experienced degradation, loss of structural integrity or need to meet new codes or standards, rehabilitation using a reline pipe may be preferred versus replacement.

Depending on the size and annular space to be filled as well as the pipe elevation between the inlet and outlet, it may be necessary to add grout in multiple stages or "lifts".

Poorly designed culverts can degrade water quality via scour and erosion, as well as restrict the movement of aquatic organisms between upstream and downstream habitat.

[9] While the culvert discharge capacity derives from hydrological and hydraulic engineering considerations,[10] this results often in large velocities in the barrel, creating a possible fish passage barrier.

Critical culvert parameters in terms of fish passage are the dimensions of the barrel, particularly its length, cross-sectional shape, and invert slope.

[16] Finally, a solid understanding of turbulence typology is a basic requirement to any successful hydraulic structure design conducive of upstream fish passage.

Researchers developed and patented the design procedure of minimum energy loss culverts which yield small afflux.

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.