By Kat Sawyer
The Watershed Project recently taught a webinar for EBMUD on Rain Gardens and Rainwater Harvesting. One of the attendees was a Master Gardener named Joni who lives in the hills of El Cerrito. She was in the process of installing a rainwater catchment system at her home with DIG Cooperative (https://www.dig.coop/). After the installation was complete, she invited me to visit her garden. Last week I took a tour of her backyard and was charmed by its many ecological features.
The story of Joni’s backyard is one of dedication and persistence that began over 20 years ago. Like many hillside homes, her backyard was a steep incline overgrown with ivy, making it a formidable place to access and enjoy. Over the course of time, she has transformed it into a delightful place in tune with the cycles of nature.
Her first step was to lay out a serpentine pathway with rope, winding it down the hillside to define a path to be dug out in order to create a Celtic labyrinth that meanders down to the lower yard. While we walked it together, she told me that a labyrinth is designed to lead away from the center toward the periphery before making its way back to the middle, simulating the sacred path of an inward journey.
Along the pathway, she has begun to construct a Hugelkultur bed made of tree limbs and stumps topped with yard cuttings.
Hugelkultur is an ancient water-wise gardening technique that builds soil by mounding biomass on top of wood in an above-ground planting bed. As the wood decays underneath, it becomes a consistent source of nutrients and heat, making it a good place to grow plants and sequester carbon. The logs and branches act like a sponge. Rainwater is stored and then released during drier times. In our climate, it requires watering once a month in the dry season.
Another point of interest along the pathway was a section of hand-built gabion rock walls that Joni constructed with rocks she sifted from her rocky Franciscan soil and wrapped in chicken wire. The word “gabion” is Italian for “cage,” and the first gabion walls were made by Roman armies with woven willow wattle. Gabion walls provide a solid form without using concrete and they look more natural because plants can grow inside them.
After walking the labyrinth through the yard, we ventured back up the hill to see her new rainwater harvesting system.
Two 530-gallon slimline rain tanks were installed by DIG last month to capture stormwater from an 800 sq ft section of roof. With an average of 25 inches of rainfall annually, these tanks will manage over 12,000 gallons per year by detaining rain for slow release and irrigation. These tanks are located at the top of the hillside, so gravity will assist the flow downhill to plants in the lower yard. In foggy weather, the first flush filter pipe also captures fog condensate from the air!
A backyard oasis like Joni’s takes years to create, but it can happen step-by-step. In the pauses between work, inspiration comes for the next task, informed by the knowledge gained from living with the space for a while. The reward is a transformation that makes the home more resilient and ecologically beneficial. Implementing techniques like rainwater catchment and organic gardening in our yards can make city environments healthier for all.