How would the flow channel of a B-3 swale be stabilized?

The flow channel of a B-3 swale is stabilized using 4"-7" stone (or a recycled equivalent), pressed into the ground, primarily because larger stone provides significant structural stability and can effectively manage water flow in the swale. This type of stabilization helps to prevent erosion by creating a durable surface that can withstand the forces of flowing water while allowing for drainage. The larger stones are also effective at dissipating energy from moving water, which reduces the likelihood of erosion occurring in the channel.

Using 4"-7" stone is particularly suitable for areas with concentrated flow, as the stones provide a robust armoring layer that protects the soil beneath from being washed away. This method of stabilization is often preferred in designs where frequent water flow may scour the channel, ensuring long-lasting protection compared to other more temporary solutions. Natural erosion control measures, like seeding, typically take longer to establish and rely on plant growth to prevent erosion rather than providing immediate physical protection, making stone an effective immediate solution in certain scenarios.