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Availability of a Draft Environmental Impact Statement, Whittier Narrow Dam Safety Modification Study, Los Angeles County, California

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Department of the Army, U.S. Army Corps of Engineers, DoD.


Notice of availability; request for comments.


The U.S. Army Corps of Engineers (Corps) announces the availability of a Draft Environmental Impact Statement (EIS) for the Whittier Narrows Dam Safety Modification Study, Los Angeles County, California for review and comment. Pursuant to the National Environmental Policy Act (NEPA). The Corps has prepared a Draft EIS for the Whittier Narrows Dam Safety Modification Study (DSMS). The Draft EIS evaluates risk management plans (alternatives) to remediate safety concerns such as overtopping and seepage. The Draft EIS describes and analyses the impacts of risk management plans (RMPs) that are formulated, evaluated and compared through the DSMS process in order to identify a recommended RMP that reduces risks to downstream life-safety and property associated with dam failure. Implementation of the recommended risk management plan would mitigate the intolerable Dam safety risk and allow the Dam to safely function as originally intended and authorized. Without this action, the Dam could fail resulting in life-threatening floods to downstream communities. The Proposed Action is needed to provide life-safety to the communities downstream of the Whittier Narrows Dam.


Written comments pursuant to the NEPA will be accepted until the close of business on January 28, 2019.


The document is available for review at:


(2) U.S. Army Corps of Engineers, Los Angeles District, 915 Wilshire Blvd., Los Angeles, CA 90017-3401.

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Ms. Deborah Lamb, U.S. Army Corps of Engineers, Los Angeles District, phone number (213) 452-3798. Questions or comments regarding the Whittier Narrows Dam DSMS Draft EIS, contact Ms. Deborah Lamb by phone or by email to or Whittier Narrows DSMS EIS

For further information regarding the Whittier Narrows DSMS, contact Mr. Doug Chitwood, (213) 452 3587, or by email to

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1. Background Information. Construction of Whittier Narrows Dam was completed in 1957 as an integral component of the Los Angeles County Drainage Area (LACDA) system of dams and channelized rivers authorized by Congress in the Flood Control Act of 1936. The Whittier Narrows Dam primary purpose is flood risk management with recreation added in the Flood Control Act of 1944 (Pub. L. 78-534). Whittier Narrows Dam is located approximately 11 miles east of downtown Los Angeles, Los Angeles County, CA. The dam protects over one million people and reduces economic damages to the communities downstream during flood events. The Corps has classified Whittier Narrows Dam as very high risk due to the potential for seepage and hydrologic issues during rare storms that could lead to failure. The DSMS and Draft EIS identify and evaluate alternatives to address these deficiencies and reduce the annual probability of failure and the Start Printed Page 64338risk to life safety to within the Corps' tolerable risk guidelines as presented in Engineering Regulation 1110-2-1156.

A Notice of Intent to prepare the Draft EIS was published on July 22, 2013 in the Federal Register. A public scoping meeting was conducted on September 11, 2013 in the City of Pico Rivera, California. The Draft EIS is available for a 45-day review period pursuant to the NEPA.

2. Risk Management Plans (Alternatives). In addition to a No Action Alternative, the Draft EIS evaluates an array of remediation alternatives including: (1) Raising the crest elevation of the dam with a 12 foot high parapet wall on top of the crest, constructing an auxiliary labyrinth spillway adjacent to the existing spillway, and a trench drain and filter blanket; (2) placing a 10 foot wide roller compacted concrete series of steps on the downstream slope of the Dam embankments with trench drain and filter blanket.

3. NEPA Scope of Analysis. The Draft EIS evaluates the impacts of risk management plans on environmental resources and the human environment. Resources initially identified in the NEPA scope of analysis as potentially significant without implementation of mitigation measures include noise and vibration and recreation.

Resources initially identified in the NEPA scope of analysis as potentially significant without implementation of mitigation measures include, but are not limited to: Water quality, noise and vibration, air quality, socioeconomics and environmental justice, land use, recreation, visual and esthetic resources, traffic and transportation, historical and cultural resources, vegetation and wildlife, and special status species.

Public Participation: As part of the public involvement process, the Corps' Los Angeles District anticipates the public meeting will be held in January 2019. The public review meeting will allow participants the opportunity to comment on the Draft EIS. Attendance at the public hearing is not necessary to provide comments. Written comments may also be given to the contact listed under FOR FURTHER INFORMATON CONTACT section.

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Brenda S. Bowen,

Army Federal Register Liaison Officer.

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[FR Doc. 2018-27114 Filed 12-13-18; 8:45 am]