Natural drainage systems are an innovative alternative to traditional stormwater management systems.
Natural drainage systems limit the negative impacts of stormwater runoff by redesigning (residential) streets to take advantage of plants, trees, and soils to clean runoff and manage stormwater flows.
Vegetated swales, stormwater cascades and smell wetland ponds allow soils to absorb water, slowing flows and filtering out many contaminants.
Guidance can be found here;