Ditches

A ditch is a man-made or naturally occurring channel used to convey water. In civil and agricultural engineering, ditches are engineered to move surface runoff away from land, prevent flooding, and drain agricultural fields, and they also serve to convey irrigation water or to channel drainage from roads and railways.

Ditches vary in construction and purpose. Open ditches are unlined and consist of excavated earth; they may be wide and shallow or narrow and deep. Lined ditches use stone, concrete, or gabions to reduce erosion. Covered or underground drainage uses perforated pipes or tile drains buried beneath the soil, sometimes with an above-ground access trench.

Design and maintenance: capacity is determined by cross-section, slope, roughness, and rainfall/runoff. Common cross-sections are trapezoidal, U-shaped, or V-shaped. Erosion control measures include vegetation along banks, riprap, or geotextiles. Sediment may accumulate and require periodic dredging or sedimentation basins. Highway and roadside ditches require maintenance to keep inlets clear and flow unobstructed.

Environmental and governance: ditches provide habitat for aquatic plants and animals but can transport pollutants; their management is often the responsibility of landowners, drainage districts, or public authorities, depending on jurisdiction. Regulations may govern drainage rights, preservation of wetlands, and water quality.