From Pasture to Percolation: One Resident’s Effort to Recharge Groundwater

A Well Aware Case Study

The Connection Between Recharge and Rural Residents

Individual residents can play an important role in protecting and enhancing our precious groundwater supply. In Sebastopol, within the Santa Rosa Plain Groundwater Subbasin, Martin Mitchell is doing just that. Mitchell is restoring his property in an effort to revitalize the land, support the return of native species, and recharge the groundwater basin. Mitchell wants to show others the value of sustainable living through changes they can implement on their own properties.

Restoring Soil Health and Groundwater Recharge

Mitchell purchased his 4-acre property in August 2020 and set out to transform the land from unproductive turf to a vibrant native landscape. Prior to his purchase, the property was a depleted horse pasture, which often flooded and ran off down the sloped property due to the soil lacking organic matter, carbon, and the ability to retain water. Mitchell sought to improve the soil health first, rebuilding the top layer with wood chips and cardboard which also helped to recarbonize the soil. He estimates he has added 4,000 yards of chips or two million pounds of pure organic matter.

In 2022, Mitchell began excavating to create bioswales, to collect stormwater runoff and help to recharge groundwater to the basin. Native plants made up much of the bioswales, including:

• Douglas iris
• Coyote brush
• Coffeeberry
• Sticky monkey flower
• Pacific wax myrtle
• Buckeye

These help to filter out pollutants in the water ensuring healthy water quality of the recharged water. His most productive bioswale, dubbed his “Quail Swale”, consists of several plants with fibrous root networks to filter contaminants and is about 70 feet long, three feet wide, and about three feet deep. In combination with his other two swales, they have a recharge potential of upwards of 50,000 gallons or more per year. He also has seen an increase of native animal species, including quail, weasels, killdeer, and frogs.

Leading by Example

Mitchell hopes to serve as an example, showing that individual residents can make a difference and be a vital part of a sustainable future. He wants to remind people to be mindful of what they are planting and how it affects the environment. Mitchell is hoping to make his property an educational center for others to visit and get inspired to make their own changes. Future projects include planting a native orchard on a yet to be used portion of his land, currently home to his flock of black belly sheep, who rebuild the soil by cycling nutrients and fertilizing the soil. He is constructing a no-emissions, off-grid, solar-powered multiple-purpose building with an ADU and a gray water system that will be fed from his laundry machine. Several other tanks on site can be filled with up to 300 gallons and used during droughts to reduce the burden on the groundwater basin. Mitchell is in the process of building a more permanent home, using shipping containers that will include solar panels to reduce his energy demands. 

Advice and Resources

Mitchell’s work is great example of how to transform unproductive turf into spaces that not only help reduce outdoor water demands, but support groundwater recharge and help the Sonoma County GSAs achieve their sustainability goals. Mitchell advised those who are looking to make similar changes to seek people with expertise to help guide the process. While Mitchell’s educational background is in gardening, he felt that the guidance of a naturalist and working with Permaculture Artisans were hugely important to his success. The Sonoma County GSA’s website, wellawaretoolkit.org, offers several similar resources to help those looking to improve their landscapes, including design templates, best practice guides, and connecting with Qualified Water Efficient Landscaper (QWEL)-certified landscapers.

Groundwater Conservation and Recharge

Restoring soil health promotes plant growth and helps to recharge the groundwater basin by allowing more water to percolate to the basin. Creating bioswales featuring native plants help to filter the water of debris and pollutants so it drains down to the basin. Bioswales on the property will help to recharge thousands of gallons of water to the groundwater basin while adding a beautiful, native landscape. If creating swales is not an option, another way that landowners can slow rain runoff and reduce invasive weeds is by putting arborist chips on contours.