Stormwater Engineering Projects

Picture of Big Tujunga Wash Mitigation Area



Please be aware that maintenance activities will be conducted throughout the Big Tujunga Wash Mitigation Area (BTWMA) beginning in February and continuing through December 2018. Work consists of quarterly invasive plant removal, quarterly trails clearing and care, and monthly wildlife maintenance to protect endangered species on site. Crews will also respond as needed to any trail issues that may arise. Crews generally will work between the hours of 7 a.m. and 4 p.m. No work will be conducted on the weekends.

This work is being performed by Chambers Group, an environmental consulting firm, under supervision of the Los Angeles County Department of Public Works.

Please be aware that planned maintenance activities may involve the use of small ATVs and/or inflatable (non-mechanized) boats to help facilitate specific maintenance tasks and that this equipment has been authorized by LA County Public Works for use onsite by the maintenance crews.

Please be watchful when riding horses or hiking in the vicinity where the crews are working. Crews will be cautious when equestrian riders or hikers are nearby, but it's best to avoid active work areas whenever possible. If you do come upon a crew, please call out to them if they do not see you so they can stop their equipment and allow you to pass by safely.

Bilingual Chambers Group biologists are often onsite during peak-use weekends. They are approachable and are happy to provide educational information about the Mitigation Area. The on-site biologists value user ideas, concerns and feedback.

The 12th Annual Trails Cleanup Day is planned for Fall 2018. Further details will be posted and distributed when available.

Chambers Group experts monitor all maintenance activities to ensure that sensitive biological resources are not negatively impacted during maintenance activities.

If you have any questions regarding planned maintenance activities, please contact the Los Angeles County Department of Public Works at


The Big Tujunga Wash Mitigation Area was purchased by the Los Angeles County Flood Control District in 1998 to compensate for habitat loss from other projects. The site encompasses approximately 210 acres of land located in the City of Los Angeles-Sunland area.

For nearly two decades the Mitigation Area's native alluvial scrub, cottonwood-willow riparian, and oak-sycamore woodland plant communities accommodated miles of winding equestrian and hiking trails and provided suitable or potential habitat for a number of endangered, threatened, and sensitive plant and wildlife species including Davidson's bushmallow, Plummer's mariposa lily, slender-horned spineflower, San Diego horned lizard, black-crowned night heron, great blue heron, Cooper's hawk, loggerhead shrike, southwestern willow flycatcher, least Bell's vireo, and Santa Ana sucker.

In December of 2017, the Creek Fire burned through the Mitigation Area, leaving these plant communities severely fire-damaged or destroyed. While goals for the Mitigation Area ultimately remain the same, the plans to reach those goals have been revised for 2018, shifting from a highly maintenance-based approach to one of restoration and maintenance.

The Creek Fire, while devastating to the Mitigation Area, has provided a wealth of opportunity to reestablish trails and restore habitat function that is essential for sensitive wildlife species to thrive. During the Mitigation Area's recovery process, implementation efforts will focus heavily on exotic plant and wildlife removal in order to support the return of native habitat and wildlife to the Mitigation Area.

Big Tujunga Wash Mitigation Area



For more information on the project or to report minor incident, please contact or phone the LA County Sheriff at (800) 834-0064.

Updated on: 09/26/2018