Long before the riparian-loving, drought tolerant California native foliage established itself, this rain garden worked to keep stormwater onsite. It takes quite a bit of technology to do so. The bioswale accepts water from the back and front gardens as well as the roof of the home via drains, an underground vessel, and a sump-pump. It can absorb this level of water in a matter of minutes. Because the soil in this area tends toward clay, another drain helps manage possible overflow. Photo: Steve Matloff, 2018