The Los Angeles River (LA River) is one of Los Angeles County, California's most valuable assets, providing flood risk management for millions of County residents. Since floods in the early 20th century cost dozens of lives and hundreds of millions of dollars in property damage, efforts have primarily focused on using the LA River for flood control. In 1996, the county developed its first LA River Master Plan (LARMP) with the goal of identifying ways to revitalize the river and create community resources through aesthetic enhancement, recreational opportunities, flood control, and environmental values.
In 2018, the county embarked on updating the 1996 LARMP, with the intent of considering the wealth of knowledge developed in the past 20 years and employing a regional approach. The master plan update focuses on creating continuous, healthy, and equitable open space and promoting water stewardship while not compromising flood control. The LA River Master Plan update follows a public process that engages local communities and seeks input from stakeholders along the LA River.
As part of the master plan update, Geosyntec is reviewing existing hydrology, water quality, and peak flow management in the river; helping the county and its regional partners establish a process for determining beneficial uses along the LA River; and reviewing and updating models and identifying flood control system capacity, existing deficiencies, and the physical condition of the river infrastructure. As project manager, Geosyntec is managing a group of subconsultants comprised of architects, landscape architects, planners, nonprofits, and public facilitators. The Geosyntec team is also researching, summarizing, and detailing existing ecosystem and habitat conditions; open space, recreation, and trails; significant community programming, cultural venues and institutions, and art policies and installations; operations and maintenance conditions; access, security, and safety conditions; and demographics, public health, and social equity issues. Sustainability and resilience planning are central to the topics described, so we are analyzing how climate and shifting resources affect the future of the LA River. The Geosyntec team will investigate utilizing the channel right-of-way and immediately adjacent properties to create 51 miles of connected and accessible open space, capture water in the channel for aquifer recharge, and improve water quality. The process is being driven with input from a steering committee, focused workgroups, and the public through community meetings at multiple locations within the 834 square-mile watershed.
The LARMP update will serve as a guidance document that unites the 51-mile LA River, providing multi-benefit solutions for managing flood risk as well as creating continuous, healthy, and equitable open space based on assessed conditions and stakeholder input. It unites regional scale planning with an implementation plan to tie proposals to clear funding paths through program-scale funding.