This sidewalk in Malmo, Sweden uses stormwater captured on the neighboring rooftop in an artful way that enhances the pedestrian experience during a rain event.
Tanner Springs Park - "All the rainwater that falls within the curb-line of the park is collected and treated within the park--a first for a Portland park. Rather than channeling the stormwater to storm drains in the street, all of it is filtered within the park. an ultra violet light system is used, as well as natural soil filtration as the water runs "downstream" through the runnels. No chemicals are used to treat the water in this closed system."
Coloco | Paysagistes / Urbanistes / Jardiniers | Place de l’Evêché
City of Spokane - Municipal Government This rainy weather gives us an opportunity to show how our rain gardens on Lincoln Street work. Instead of running down the hill, the stormwater is captured by the garden, where it filters through the soils in the garden. The soils essentially treat the water. Any water that isn't absorbed within the planter is collected and sent to the pond in Cannon Hill Park.
stormwater planter 2.bmp (358×290)
Natural pools are closed ecosystems sealed by synthetic pool liners. In addition to mechanical circulation systems, the pools have non-chemical filters to catch additional small particles. The main water-cleaning takes place in the microorganisms and microbes... We need water plants to create a habitat for these elements (that clean the water). http://expandinghorizons.biz/html/pristine_swimming.html#