Shadelands Drive & N. Wiget Lane Bio-retention Basin Project Completed
The City of Walnut Creek constructed a new bio-retention basin at the southwest corner of Shadelands Drive and N. Wiget Lane, which will slow, filter, and treat storm water and roadway runoff before the water enters storm drain systems and waterways.
The Walnut Creek Public Works Department completed construction on the Shadelands Drive and N. Wiget Lane Green Infrastructure Improvement Project in May 2026. City workers installed a new, aesthetically pleasing bio-retention basin, drought-resistant plants, and an irrigation system at the southwest corner of Shadelands Drive and N. Wiget Lane.
Bio-retention basins, often called “rain gardens,” are shallow, landscaped basins used to slow, filter, and treat stormwater and roadway runoff — which contain sediment, grease, oils, and other pollutants — before the water enters storm drain systems and waterways. Stormwater is directed to the basin and then percolates through the system of perforated pipe and drain rock underneath, and soil and planting on top, allowing the water to slowly soak into the ground and leave no standing water for any great length of time.
The City worked with UC Master Gardeners to help identify the most effective and water-wise plants and soil mix to use as a part of the bio-retention basin system, which included more than 80% native plants to support a healthy pollinator habitat.
Before: At the southwest corner of Shadelands Drive and N. Wiget Lane, stormwater would pool and cause soil erosion and unfiltered runoff. Additionally, there was a large sidewalk gap along N. Wiget Lane and Shadelands Drive that needed attention to ensure vehicular and pedestrian safety.
The completion of the bio-retention basin was part of a larger project to improve pedestrian safety and access along the southwest corner of Shadelands Drive and N. Wiget Lane, which began in late 2023. The project involved closing a sidewalk gap along N. Wiget Lane and Shadelands Drive by constructing a new 10ft-wide sidewalk that wraps around the Master Gardeners Our Garden site; the bio-retention basin was built between the new sidewalk and the east fence of the garden. Additionally, the City improved the corner curbs with curb ramps and 15ft-wide curb extensions.
Before: The construction of the bio-retention basin at the southwest corner of Shadelands Drive and N. Wiget Lane was one part of a comprehensive roadway improvement and pedestrian safety project.
After: Completed roadway and safety improvements include new corner curbs with curb rampls and 15ft-wide curb extensions.
After: Facing south at the corner of Shadelands Drive and N. Wiget Lane, improvements include the new 10ft-wide sidewalk that closed the previous sidewalk gap, curb ramps, roadway markings, and the bio-retention basin.
