Road side drains

Engineers have developed some solutions to the final problem of road drainage. The differences in design are often forced by changes in geology and terrain, although some designs don't seem to be always economically justifiable for low traffic volumes. Certain designs are inherently safer than others whilst still fulfilling an engineering function. An understanding of the critical elements of drainage design may result in a very much safer and cost-effective solution.

Conventional Vee-shaped drain:

Vee-shaped drains are often used as a low-cost alternative to the more hydro-dynamic trapezoidal drains. I here am many variations of the standard shape with ‘J and ‘y’ drains incorporating a lip on the roadside edge. The vee-shape is ideally suited to flat environments where there are many rooms to include a shallow roadside slope at a coffee cost. it's also preferable to produce a small slope on the verge side edge to help the vehicle in regaining the road carriageway.

Trapezoidal Drain:

The trapezoidal drain has better hydro-dynamics than the vee-shaped drain but remains easy to make employing a grader and digger. The drain will be shielded from scouring by the addition of gravel, grass, or rip-rap. The trapezoidal drain is ideally suited to flat environments in high rainfall areas or alongside roads running through large rainfall catchment areas. Errant vehicles leaving the carriageway are also ready to regain control if the side slope isn't any steeper than 1:4:5 gradients.

Flat-Bottomed Drain:

The flat-bottomed drain has good hydro-dynamics. The hydraulic capacity may be improved by widening the drain or deepening the soffit, although the depth should preferably not exceed 150mm. this kind of drain is good for flat environments, cuttings, or hilly terrain where space is restricted. The vertical edge to the drain may prevent errant vehicles from having the ability to regain control but, providing the depth is below 150mm, the danger of rollover accidents is negligible.

Parabolic Dish Drain:

The parabolic dish drain has good hydro-dynamics but an occasional capacity. The capacity may be improved by deepening the parabola or by increasing the number of turn-outs. This type of drain is right for low rainfall situations or routes with a high number of roadside properties or accesses. A deeper drain is often constructed further off from the road to gather run-off from outlying land if required.