Valley Glen, Los Angeles, California

Tujunga Wash Greenway and Stream Restoration Project

Background

Sign showing Tujunga Wash Greenway and Stream Restoration Project
Source: Los Angeles County Public Works

The Los Angeles River and its tributaries have, over the past 60 years, been channelized, buried, diverted, and otherwise modified—primarily for flood control and convenience. The surface waters in the Los Angeles region now flow almost entirely through pipes and engineered, concrete channels fenced off from neighboring communities (for safety reasons).

Over the last few years, residents, local officials, water resource professionals and landscape architects have worked together to revitalize Los Angeles's river system, looking beyond flood control to provide additional benefits: water quality, recreational, aesthetic, habitat, ground water recharge and water supply, to name a few. The City of Los Angeles has invested in bikeways, bridges, parks, bike paths, public art, and street improvements. The City also sponsored the Los Angeles River Revitalization Master Plan, completed in 2007, which strives to establish environmentally sensitive urban design, land use, and development guidelines for the River zone to enhance economic development, provide amenities to the community, allow public access to the river, and support the ecological and flood control functions of the river ecosystem.

The County of Los Angeles (1996) adopted the Los Angeles River Master Plan, and has established important landscaping and signage guidelines for the River. Currently, the U.S. Army Corps of Engineers is engaged in several studies to restore a functioning ecosystem within selected areas of the channel. Many grants have been received for trees, pocket parks, bikeways, and other features that contribute to the greening of the River corridor.

According to the Los Angeles River Revitalization Master Plan, nonprofit groups have been instrumental in raising public awareness of the River's potential, including the Friends of the Los Angeles River, TreePeople, North East Trees, The River Project, the Arroyo Seco Foundation, The Coastal Conservancy, and the Trust for Public Land. Over the long term, these groups have sponsored public education programs, river cleanups, monitoring studies, and physical improvements, and they have sponsored and implemented a number of revitalization projects, including pocket parks, landscape improvements, and water quality treatment areas. The following are examples of the valuable work by nonprofit groups:

  • TreePeople produced the Sun Valley Watershed Management Plan (with the County of Los Angeles) and the Hull House demonstration site.
  • North East Trees developed numerous greenway parks and with the Arroyo Seco Foundation produced the Arroyo Seco Watershed Management Plan.
  • The River Project produced the Tujunga/Pacoima Watershed Management Plan as well as earlier studies and planning efforts for Tujunga Wash, Taylor Yard and, with the County, implemented the Valleyheart Greenway.

Other efforts have focused on the watershed—particularly along the rivers in the basin. The Mountains Recreation and Conservation Authority and its partner organization, the Santa Monica Mountains Conservancy, along with the Rivers and Mountains Conservancy, and the Los Angeles and San Gabriel Rivers Watershed Council are all engaged in planning, designing, and building community, neighborhood, open space, parks and trails along the River and throughout the County.

These projects demonstrate that greening publicly owned, underutilized lands provides an important environmental education function that increases awareness of the value of rivers and their relationships to the entire watershed. Because the river system has been so significantly modified over the years, the changes to the system must occur gradually and in stages.

On-Site BMP Examples

One of the newly completed revitalization projects in the Los Angeles region is the Tujunga Wash Greenway and Stream Restoration Project. Located in Valley Glen, California, a neighborhood in Northern Los Angeles, the $7 million, 1.5-mile project diverts an average of 325,000 gallons per year of stream flow from the existing flood control channel through a newly created, natural streambed. The project grew out of a multi-agency partnership between Los Angeles County, the City of Los Angeles, and the Mountains Recreation and Conservation Authority, which includes the Santa Monica Mountains Conservancy and the Rancho Simi and Conejo Recreation and Park Districts. The Mountain Recreation and Conservation Authority will provide long-term maintenance of the project area. Funding for the project came from state and county government sources.

Image shows chain link fence in poor repair Image shows new access point with iron gate and stone columns
Before: access to the Wash and adjacent areas was forbidden (Source: Los Angeles County Public Works). After: the greenway entrance is enhanced by stone columns and an artful iron gate (Source: Los Angeles County Public Works).

One of the main objectives of this project is to recharge groundwater to the San Fernando Valley groundwater basin, an important natural function lost when the Wash was channelized in the early 1950s. Groundwater is an important source of water for the Los Angeles region, accounting for 15 percent of the areas water supply (85 percent of water is currently imported from other areas). Sponsors of the Tujunga Wash project estimate that the recharge achieved through this project will provide enough water for 760 families of four annually. As climate change threatens water supply reliability in Southern California, in-situ sources such as the groundwater basin will become increasingly important.

The project is designed to balance groundwater recharge, flooding, and erosion concerns and to reverse some of the effects of past channel modifications. The enhancements to the Tujunga Wash fit into the larger framework of a holistic, watershed approach emphasizing multi-benefit projects that address flood control, groundwater recharge, and water quality, and that also look at on-site BMPs as an important component of a watershed-based strategy.

Community amenity is also an important concern. The new stream corridor was designed with California native trees and plants to reflect the region's arid environment. A greenway with a paved trail for running, walking, and biking spans the length of the restored channel and designers incorporated picnic tables at the park entrance and benches along the length of the trail. Dogs are allowed in the park (on leash) as long as owners collect their waste.

A before-and-after comparison at the site shows the drastic aesthetic improvements that can be appreciated by neighbors and park users even if they're unaware of the groundwater recharge benefits of the project. The revamped site features new, green fencing and vegetation compared to the rusted, chain link fence and bare dirt banks that existed before. As this project matures, vegetation will continue to develop and the channel should maintain a natural form.

Tujunga Wash before restoration featuring bare slopes, a concrete channel, and rusted fencing The Wash after project completion, showcasing a natural streambed, native vegetation, and new fencing
Before: Tujunga Wash before restoration featuring bare slopes, a concrete channel, and rusted fencing (Source: Los Angeles County Public Works). After: The Wash after project completion, showcasing a natural streambed, native vegetation, and new fencing (Source: Los Angeles County Public Works).

Local officials see the project as a success story that will serve as a pilot or demonstration project for future stream restoration activities undertaken as part of the Los Angeles River Master Plan and nationwide. According to Joseph T. Edmiston, executive director of the Santa Monica Mountains Conservancy, "There are dozens of similar projects on the drawing board. This one really shows that we can combine recreation, aesthetic amenities and river function . This is the first real example of re-establishing important natural function by recharging the aquifer." Los Angeles City Councilwoman Wendy Greuel emphasizes that "this is about a bigger plan for sustainability and livability along the river. This is another instance where the city and county are working together, along with the Army Corps of Engineers, as we look at the entire Los Angeles River Master Plan, a whole revitalization to give us more green space and to be environmentally friendly." (Anderson, no date.)

Plans are underway for Phase 2 of the project, which included a half-mile extension of the greenway upstream of Vanowen Street for $7.5 million and an $18 million groundwater recharge project at Hansen Dam (further upstream). Elsewhere in the Los Angeles area, other parts of the Los Angeles River Master Plan are unfolding as projects are funded and implemented. The vision of the plan as a whole—to bring the streams back to a more natural state and provide public amenities serving the communities' recreational and water resource needs—is a noble one and is worth watching in the months and years to come.

Opening ceremony for the Tujunga Wash Greenway and Stream Restoration Project
Opening ceremony for the Tujunga Wash Greenway and Stream Restoration Project (Source: Los Angeles County Public Works)

Additional Information

    Los Angeles River Master Plan. 1996 plan to enhance and restore some of the ecological function of the Los Angeles River and its tributaries.

    http://ladpw.org/wmd/watershed/LA/LARMP/

    Los Angeles River Revitalization Master Plan. 2007 plan sponsored by the City of Los Angeles to revitalize the Los Angeles River system.

    http://www.lariverrmp.org/

    Tujunga Watershed Project. This site includes background about the project, links to the Tujunga/Pacoima Watershed Plan, and educational curricula tailored to different grade levels.

    http://www.theriverproject.org/tujunga/

    The River Project. A Los Angeles regional organization dedicated to planning for natural resource protection, conservation and enhancement in Los Angeles County.

    http://www.theriverproject.org/

References


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