Pacoima, which is a rendition of Pacoinga Village by the Fernandeño Tataviam tribe, is one of the oldest neighbourhoods in Los Angeles. Surrounded by factories and paved over with concrete, the community is now embarking on an urban revival project led by the City of Los Angeles Sanitation & Environment, Pacoima Beautiful, and The Trust for Public Land.
As the first project to be unveiled for Pacoima Beautiful’s Urban Greening Plan, Bradley Plaza Green Alley transforms an underused alleyway between a major street and a low-income housing community into a shared space that provides ADA-accessible amenities, introduces nature into the city, reduces the heat island effect, and manages stormwater. As the project’s engineer and consultant, Arup provided infrastructure expertise including stormwater management, conceptual lighting design, sustainability consulting, Geographic Information System (GIS) consulting, and community outreach support.
Involving local communities
Throughout the entirety of the project, Arup and the project team engaged with local residents to understand their needs and tailor solutions to best serve the community. At the start of the project, Arup introduced three concept schemes at a local workshop, and community members were encouraged to choose the elements and overall design they liked best. We consolidated feedback from the event and produced a design to meet their needs and priorities, which included shaded areas, artwork that showcases the local culture, and more. The project team also conducted five focus group outreach events, including one with a youth environmental group and one with a coalition of mothers who live in public housing adjacent to the project site.
By engaging with the Fernandeño Tataviam tribe, Arup and the project team were also able to incorporate Fernandeño Tataviam language and indigenous art throughout the space.
2M gallons annual rainwater capture capacity
1,346trees and plantsplanted throughout the Alley
We’re redefining how we manage stormwater in Los Angeles. In a dry city that is prone to flash floods, we’re enabling places to capture, hold, and let go of stormwater safely. ”Anthony Kirby Associate Principal
Improving stormwater management
The alley had traditionally carried dirty stormwater into the street, which caused flooding in the area due to the deteriorated condition of the alley infrastructure. Arup, working with landscape architects Rios Clementi Hale Studios (RCHS), redefined the geometry of the alley which now directs stormwater into a series of planters that will capture, hold, and release water to a subsurface infiltration trench. The water is filtered as it passes through vegetation, which enables the groundwater aquifer under the alley to be replenished with treated stormwater. As a result of the design, the project exceeds the City of Los Angeles’ Low Impact Development and stormwater capture requirements, with a capacity to capture 2M gallons of rainwater per year.
To help visualize the project and any water-related risks, Arup used GIS technology. We used watershed maps to lay out the site’s stormwater features and provided the required clearances to adjacent buildings for the stormwater infiltration facilities.
Landscaping elements for improved health and wellbeing
The design team introduced trees and shading to reduce the urban heat island effect, further improving public health. Staying true to the spirit of Pacoima, the project incorporates a ground painted in a wavelike pattern mimicking rushing water. The project uses a pavement street bond, or asphalt colouring, that increases the cooling effect, to enable the painted ground to reflect heat instead of absorbing it.
What I find remarkable is how culturally aware the project is. Pacoima Beautiful engaged the Fernandeño Tataviam tribe who historically owned the land, and the design incorporates Fernandeño Tataviam symbols and interpretive signs that translate to the Tataviam language. ”Vanessa Thompson Civil and Environmental Engineer
It’s a community-led process, which leads to a successful project that addresses the needs and desires of the local community. ”Vanessa Thompson Civil and Environmental Engineer
Targeting Envision certification
Bradley Plaza Green Alley aims to achieve Envision Platinum certification, which recognizes sustainability in infrastructure projects. The project sits well within its surroundings, exceeds Los Angeles’ low impact guidelines for stormwater management, uses recycled materials, incorporates landscaping that improves public health, and serves the needs of the community – making it an excellent fit for the certification.
Bradley Plaza Green Alley is funded through the City of Los Angeles Housing and Community Investment Department, Community Redevelopment Agency (CRA/LA), LA Sanitation and Environment, Los Angeles Department of Water and Power, Los Angeles Waterkeeper & The Liberty Hill Foundation, California Natural Resources Agency, The Boeing Company, and Wells Fargo Foundation. Additionally, the project had broad support from the San Fernando Gardens Housing Authority, whose residents live adjacent to the site.
All images courtesy of the Trust for Public Land.