Stormwater filtration systems from the Philadelphia Water Department’s "Green City, Clean Waters" program. Click image for link to full profile and visit the slowottawa.ca boards >> https://www.pinterest.com/slowottawa/
Stormwater planters are structural landscaped reservoirs used to collect, filter, and/or infiltrate stormwater runoff, allowing pollutants to settle and filter out as the water percolates through the planter soil before infiltrating into the ground below or being piped to its downstream destination. Click image for details, and visit the Slow Ottawa 'Streets for Everyone' board for more sustainable design ideas.
Similar to a sieve, the willows allow water to flow through but trap the sediment back. Within a year, these structures can trap up to 10cm of sediment. Over time, this increases as the willows become more established and more sediment can be kept back. After 20 to 30 years, the vegetation will have complete cover and sediment erosion is almost completely stopped.