By Matt Freiberg
Imagine looking down at the Bay Area from a bird’s eye view. How have our homes, offices, parking lots, and other built structures shaped the ecology of the land? Our city neighborhoods and streets are designed to prevent flooding. These urban engineering developments have been effective in creating comfortable neighborhoods; however, the ever-growing swaths of impervious surfaces are also effectively altering the environment in unexpected ways.
Under normal conditions, rainwater is detained by plants and absorbed into native soils. When the land is covered in pavement, rainwater can no longer permeate the subsurface and is rapidly carried to creeks and streams lower in the watershed. Elevated water velocities scour stream banks, degrade natural habitat, and ultimately reduce biodiversity. Increased urban runoff also inundates fragile creek ecosystems with high levels of contaminants such as gasoline, motor oil, and copper from car break pads as well as nutrients and chemicals from lawn fertilizers and Industry.
While city and state planning commissions are starting to wake up to these issues, we are still years away from having any comprehensive regulatory effort to deal with the environmental impacts of storm runoff. However, large gains can be made from private citizens doing their part in their homes, schools, and businesses. Widespread application of Low Impact Development (LID) strategies such as the use of rain gardens, bioswales, and rainwater harvesting systems can retain significant amounts of rainwater on-site instead of ushering it into our creeks and streams.
Rainwater harvesting systems in particular can provide multiple benefits for home users. First, they help protect local riparian communities by reducing the amount of water flowing into a creek. Second, depending on the size of the system installed, homeowners can augment their water supply by using captured rainwater for outdoor irrigation or for indoor non-potable water uses, such as water for flushing toilets or washing dishes.
The Watershed Project is constructing rainwater harvesting systems around the Bay Area. One such system, funded by the San Francisco PUC, will be built at the Alice Fong Yu Alternative School in San Francisco in partnership with the Alice Fong Yu Parent Teachers Association. The plan consists of draining the roof of a small shed in the school garden, capturing the rain in a cistern and using the rain to water the school garden. Parents, students, school officials and community volunteers will be involved in all steps of the process – from installing the rainwater harvesting system, to designing the educational signage and planning the ribbon cutting ceremony. Most important, installation of the rainwater harvesting system will be added to the current garden curriculum at the school to teach students about the importance of Low Impact Design strategies.
There is no denying that cities will continue to grow. However, we do not have to commit ourselves to outdated development norms. We should and must choose to manage rainwater as a resource instead a nuisance. The Watershed Project looks forward to bringing demonstration projects to communities around the Bay Area to ensure that we preserve the integrity of our precious watersheds for years to come.
If you’re interested in partnering with the Watershed Project to develop a rainwater harvesting system or another LID project, contact matt@thewatershedproject.org to explore opportunities.
