One of the reasons I’ve always been so enthusiastic about green roofs is their contribution to stormwater management. Green roofs can capture 60-80% of rooftop rainwater runoff so less water is directed into storm drains and ultimately the ocean. A green roof becomes a strainer for whatever water does end up flowing to the storm drains, removing a lot of the particles, chemicals, pollution and other “bad stuff” which would otherwise run into our ocean.
So I was extremely happy to see the City of San Diego’s new Sustainable Landscape Guidelines created in partnership with the San Diego County Water Authority. These guidelines focus on ways homeowners can create sustainable landscapes with watershed development in mind, harvesting rainwater and prevent pollution.
What’s so important about watershed? What is watershed? Watershed is any area water including rain or snow flows through, including water running downhill into streams, rivers, lakes, or oceans. Forests, grasslands, deserts, agricultural land and cities are all part of the watershed.
Natural watershed absorbs and holds onto a lot of the water, so it is available for plants when needed. Some becomes groundwater deep under the watershed. But when we replace our canyons and open spaces with impermeable surfaces like buildings and parking lots, water runs off the area. There is no chance for it to be absorbed and provide a release of moisture. There is an increased chance of erosion, and pollutants are washed off the surfaces and end up on our waterways.
Anything we can do as individuals to replace these lost watersheds with our landscaping including green roofs (and living walls to an extent) helps restore nature’s water cycle and prevent pollution.
Because of our recent drought, many of us are ripping out water-thirsty lawns and replacing flower beds with hardscaping, artificial turf, and similar features. In doing so we lose many little bits of watershed. Water runs off your hardscaping into drains and is lost to the eco-system until it hits the ocean along with all the pollutants in your yard any rain or irrigation runoff washed over. Two words for you homeowners who don’t think your yard has any pollutants: Dog poop.
The City of San Diego’s guidelines suggest ways you can save water without destroying watershed. Creating basins or bioswales and using rainwater harvesting cisterns and barrels are a good start. If you’re installing a new landscape design, keep your property’s water flow patterns and existing irrigation in mind to minimize runoff.
The great news: you don’t have to figure out all the solutions yourself. The San Diego County Water Authority’s Water Smart San Diego website offers free advice on adopting water conserving practices both for your home and business. The new Sustanability Guidelines are posted on the website here.
There are classes and workshops including a four-class series held at different locations throughout San Diego County. You can apply here – it’s free, but there is a waiting list because the program is so popular.
You can access a series of six instructional YouTube videos through the Water Smart San Diego website for do-it-yourself instructions on creating a sustainable landscape. Each segment is only five minutes long. You can start with the videos, and still attend the workshop classes later.
It’s crazy not to take advantage of all of these resources. If you’re a water customer or a taxpayer in San Diego County, you’ve already paid for all these tools. It’s one of those uses of my tax dollars that is well worth the investment in my opinion.
You can find the Sustainable Landscape Guidelines on the Water Smart San Diego website here at this link.