What material do the wing walls of median inlet protection include?

The correct choice of material for the wing walls of median inlet protection is impermeable sheeting. This choice is significant because impermeable sheeting acts as an effective barrier to prevent water and sediment from passing through. By using 10 ML (mil) impermeable sheeting, the design provides a robust structure that not only hinders the infiltration of water but also effectively controls sediment erosion and sedimentation near inlets during rain events.

The impermeable nature of this material is critical for median inlet protection, as it helps direct runoff towards the inlet while minimizing the risk of sediment accumulation, which can cause the inlet to become clogged. This is particularly important in urban and developed areas where there is increased surface runoff, and sediment control is essential for water quality management.

Other materials listed, such as nonwoven geotextiles, woven slit film geotextiles, and woven monofilament geotextiles, while effective in other erosion and sediment control applications, do not provide the same level of impermeability needed for constructing wing walls that protect the median inlet. Instead, those materials typically allow some degree of water percolation, which is not suitable for the specific purpose of inlet protection that demands a high level of runoff control and sediment blockage.