Alta Transforms South LA with Green Alleys: Innovative Designs and Stormwater Capture Create a Sustainable Urban Oasis

Alta led the design team for a network of green alleys in South Los Angeles which completed construction in January 2023. The design included subsurface stormwater capture via infiltration galleries, planters within the alleys to calm traffic and provide landscape areas, new parkway swales at cross-streets to capture additional runoff, and thematic surface treatments related to neighborhood history. Alta’s role included managing the project’s concept and schematic design, design development, construction documents, bidding assistance, and construction support.

The Alta team balanced innovative design strategies with approved city standards and reconciled conceptual stormwater capture plans from grant applications with real-world topography and surface conditions. Additionally, the team managed private encroachments into public rights-of-way, including protection in place, relocation, and property owner expectations.

These projects were funded through a combination of California water quality grants.