Stormwater Engineering Projects

Picture of Big Tujunga Dam


Availability of Draft IS/MND:

A Draft Revised and Recirculated Initial Study/Mitigated Negative Declaration (IS/MND) has been prepared and is available for public review. Los Angeles County Public Works is soliciting comments from members of the public, organizations, and government agencies on the Draft IS/MND.

Click here to access the Notice of Intent, published on September 24, 2021.

Click here to access the Draft Revised and Recirculated IS/MND (excluding appendices).

Draft IS/MND Public Meeting:

A public meeting was held virtually on Thursday, October 14, 2021. The presentation slides can be accessed in the Resources Section below.

Click here to view a recording of the public meeting.

Submitting Comments:

Comments on the Draft IS/MND can be submitted in writing to the mailing address, email address, or by fax. Comments must be submitted no later than Monday, October 25, 2021, which marks the end of the review period.

Mail - include a return address and contact name in your agency
Los Angeles County Public Works
Stormwater Engineering Division, Sediment Management
P.O. Box 1460,
Alhambra, CA 91802-1460

Email - include 'Big Tujunga Reservoir Restoration Project IS/MND' in the subject line

Fax - include a contact name in your agency
(626) 979-5436

Tentative Schedule:

The project bid period is anticipated in Summer 2022. Activities at Maple Canyon Sediment Placement Site are scheduled to begin in Fall 2022 before activities at Big Tujunga Reservoir begin in Spring 2023.


The 2009 Station Fire was the largest fire in Angeles National Forest (est. 1892) recorded history and burned over 160,000 acres in the San Gabriel Mountains. Approximately 87% of the watershed tributary to Big Tujunga Reservoir was burned, making sediment deposition inevitable during subsequent storm events. The storms that occurred in the wet seasons after the fire increased sediment accumulation in the reservoir by more than one million cubic yards.

The sediment in the reservoir can impact the operation of the valves and reduce the capacity for water conservation and flood control. Sediment removal is necessary to maintain the operability of the dam and protect the communities and environment downstream of the dam.

Pursuant to the California Environmental Quality Act (CEQA), an Initial Study/Mitigated Negative Declaration (IS/MND) was originally prepared in 2013. A Revised and Recirculated IS/MND has been prepared and available for public review.

Big Tujunga Reservoir before the Station Fire
Big Tujunga Reservoir after the Station Fire
Pursuant to the National Environmental Policy Act (NEPA) an Environmental Assessment (EA) is being prepared. A public scoping meeting will be conducted by the United States Army Corps of Engineers.

Maple Canyon Sediment Placement Site Big Tujunga Reservoir Project Map Photo Taken After Big Tujunga Dam Seismic Rehabilitation and Spillway Modification Project



For more information about the project, or to be added to the project mailing list, please email or call (626)458-6119

Updated on: 10/21/2021