Aligning Infrastructure And Environmental Priorities
Sustainable water design takes center stage at Earvin “Magic” Johnson Park
By Gary Lai
Photos: MIG
By 2050, the population in California is expected to increase to 50-million people, while rainfall is projected to decrease by 10 to 15 percent due to climate change. With Californians using the equivalent volume of water of Shasta Lake—the state’s largest reservoir—every 40 days, a new model for urban-water use is being considered at every level of government.
The renovation of Earvin “Magic” Johnson Park in Los Angeles County demonstrates how urban-park design can respond to water-conservation needs by renovating older, water-intensive, man-made lake infrastructure into a renewable water resource and community amenity. The project utilizes and treats storm-water runoff from a 375-acre watershed not only to bring to life the park’s original ecosystem habitat through the creation of wetlands but to clean and use the runoff water as an irrigation source for the entire park.
The resulting effect is enhanced by a lakeside community loop trail with picnic areas and scenic viewpoints, a destination children’s play area, and outdoor classrooms. The park is located in the Willowbrook community of South Los Angeles, which has been the center of protests and civil unrest in the black community over the past century. It is very important that the park be anchored by a new event center, which stretches along the lake and offers indoor and outdoor social spaces that connect visitors with the water and landscape.
The project updates a park that was initially opened in 1994. The project was championed by former County Supervisor Mark Ridley-Thomas and commissioned by Los Angeles County Parks and Recreation and Los Angeles County Development Authority, in partnership with Los Angeles County Public Works, after being approved by the Los Angeles County Board of Supervisors in 2016. The Los Angeles-based firm AHBE Landscape Architects, now integrated with Berkeley-based MIG and operating as AHBE | MIG, developed a conceptual master plan for the 120-acre park. The firm served as the prime design consultant for the $70-million Phase 1-A renovation, and current additional renovations.
The outcome of this project has been to transform a widely used community-based park into something more—an interactive and dynamic center of learning, nature, and engagement that is powered through environmentally sustainable design and the effective use of treated storm water.
The most recently completed phase opened to the public this year. AHBE | MIG collaborated with 20+ sub-consultants, including Paul Murdoch Architects, which designed the park’s 20,000-square-foot community event center, and Pacific Advanced Civil Engineering Inc. (PACE), which designed the storm-water treatment and recapture system. Together, these elements of landscape design, architecture, and engineering have created a nature oasis and vastly new park experience for visitors.
Getting Started
The Los Angeles County Department of Parks and Recreation led a comprehensive and community-driven process to prioritize new amenities for the park, and the master plan was developed and adopted in 2015. The plan outlines features to be built over the next two decades. The storm-water capture and treatment functionalities were developed through close coordination with PACE and Los Angeles County Public Works, which considers the project a template for such systems regionwide.
“As the county’s builder, Los Angeles County Public Works is constantly looking for ways to improve a community’s quality of life through investments in public infrastructure,” Los Angeles County Public Works Director Mark Pestrella says. “This latest phase of park improvements includes a $28-million investment in water resiliency, including biofiltration gardens and an engineered-treatment wetlands that will clean neighborhood runoff using nature-based solutions.”
Capturing Storm Water
Storm water is first diverted from a local watershed. The park is part of the 375-acre Compton Creek Watershed, a major contributor of water to the Los Angeles River, draining an area of approximately 42.1 square miles. The Compton Creek channel begins in the City of Los Angeles near Main and 107th Street, then flows generally south 8.5 miles to the confluence with the Los Angeles River in Rancho Dominguez. Storm water flows through the watershed to the creek channel, which empties to the Pacific Ocean. Located entirely within the alluvial, coastal floodplain of the Los Angeles River, this low-gradient stream was historically dominated by freshwater marshes and willow-cottonwood forest. Currently, the Compton Creek watershed area supports a population of more than 700,000.
For the park’s upgraded design, a diversion pump system was developed to capture and siphon water from the storm-water system running under El Segundo Boulevard to the park’s newly created micro-treatment center that uses a combination of traditional chemical and mechanical water treatment and natural treatment through a constructed wetland along the lake edge. In this way, the park can process as much as 12 acre-feet—or 3.9-million gallons—of water from a significant water event.
Biofiltration System
The water is then treated. The park had two man-made lakes that were filled with potable water but lacked a circulation system. The new improvements tie the lakes to the storm-water system, filling them with treated recirculating storm water. The lake water is then used to irrigate the entire 130-acre park. The north lake remains essentially unimproved, other than benefiting from the significantly cleaner water circulated through it. The south lake’s shape was redesigned to allow more water capacity, to incorporate biofiltration with the freshwater marsh habitat, and to connect community experiences and social spaces with the lake and wetlands.
The diversion pump system takes raw storm water and separates out any solid waste and debris. The water is then pumped through a series of 24-inch-diameter pipes to the micro-treatment plant, which provides secondary chemical and mechanical treatment. The plant sends the treated water to the various discharge points in the wetland areas for final polishing. As an additional benefit, the lakes now act as a treatment and storage facility for runoff into Compton Creek. The 85th-percentile storm-water flow is treated for pollutants and settlements using the park’s system rather than following directly into Compton Creek and into the Pacific Ocean.
Park Irrigation/Landscape
The treated storm water fills the lake and is recirculated to irrigate the entire park land, creating a habitat for resident and migratory birds, insects, and other urban wildlife. The project incorporates some of Southern California’s vital native-plant communities, including Coastal Sage Scrub and Freshwater Marsh. This, in turn, influences the local ecology by altering soil moisture, which provides shade, protection, and food for animals. Such wetlands have been in decline in Southern California, so the project offers a way to restore the natural ecosystem. Some of the native-plant species integrated in the park design were chosen to attract natural pollinators such as bees, butterflies, and hummingbirds.
A Community Center
A key part of the project is the LEED Gold-certified community event center, designed by Paul Murdoch Architects, to complement the lake and the entire park. The 20,000-square-foot center stretches along the lake to offer indoor and outdoor social spaces with generous views of the water, while also featuring large multipurpose rooms for community events, classrooms, and a commercial kitchen. Sustainable features of the building include overhangs and piers to shade the abundant glass walls, and photovoltaic solar panels on the high roof. But the main, sustainable feature is its social function as a place where the community can now come together. The main community room is the only one of its kind in South Los Angeles. The room also features a full-wall mural, “The Guardians,” by Carla Jay Harris.
“As the overall project demonstrates, a significant investment in sustainable design in urban parks can help activate and nourish communities through education, social equity, and reconnection with the natural environment, providing long-term benefits to us and our restored public spaces,” says Paul Murdoch.
Incorporating Learning And Play
The improvements to Earvin “Magic” Johnson Park ultimately are about creating an experience that brings together the community through the natural and physical realm, including additional community social spaces and a wedding lawn.
Encouraging health, wellness, and education is also incorporated into the park design. The park’s half-mile loop trail and children’s area with splash pad encourage movement and exercise. Education is supported through open-space classroom areas and explanatory exhibits that identify natural plant and animal life.
“In the heart of the urban community of Willowbrook, Earvin “Magic” Johnson Park will be the ultimate destination where fitness, programming, and wetlands are laid out to provide play, health, and leisure opportunities for children and all demographics for generations to come,” says Los Angeles County Department of Parks and Recreation Director, Norma E. García-González.
Gary Lai is a Principal and Director of Regenerative Design for AHBE | MIG. Reach him at glai@migcom.com.
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Project Elements
Phase 1-A completions of the Earvin “Magic” Johnson Park include:
A half-mile lakeside community loop trail with picnic areas
Scenic viewing points
A destination children’s play area with splash pad
Outdoor classrooms and educational interpretive graphics describing the environmental story of the park
California native Coastal Sage Scrub and Freshwater Marsh wetland habitats
Community social spaces
A wedding lawn.
California Natives
Some of the native-plant species integrated in the park design include:
Artemisia californica (California Sagebrush)
Eriogonum fasciculatum (California Buckwheat)
Salvia leucophylla (Purple Sage)
Salvia mellifera (Black Sage)
Heteromeles arbutifolia (Toyon)
Salix lasiolepis (Arroyo Willow)
Schenoplectus spp. (Bulrush)
Juncus acutus, Typha (Cattail)