Intent To Prepare a Draft Environmental Impact Statement for the San Diego Shoreline Feasibility Study, Oceanside, CA

AGENCY:

Department of the Army, U.S. Army Corps of Engineers (USACE), DOD.

ACTION:

Notice of intent.

SUMMARY:

The Los Angeles District of the USACE will prepare a Draft Environmental Impact Statement (DEIS) to support the San Diego Shoreline Feasibility Study, Oceanside, California. The Study Area includes the shoreline between Oceanside Harbor and the Agua Hedionda Lagoon within the cities of Oceanside and Carlsbad in northwest San Diego County. The study area shoreline is approximately seven miles in length. The project environment includes predominantly beach, coastal strand and/or marine inter-tidal/littoral/pelagic zones.

The predominant problem that threatens the shoreline is continual beach erosion averaging 1.1 meters per year, despite the considerable amount of beach fill deposited, (totaling approx. 2.3 million cubic meters), on a periodic basis. Causes for this erosion has been attributed to upcoast harbor construction, dam construction, storm damage, and river sand mining.

The loss of beach width and increased exposure of property has resulted in increased coastal damage, safety issues, and loss of recreation opportunities. This feasibility study will focus on addressing the problems and needs cause by beach erosion. The DEIS will analyze the potential impacts (beneficial and adverse) on the environment for the range of alternatives, including the recommended plan.

The Los Angeles District and the City of Oceanside will cooperate in conducting this Feasibility Study.

ADDRESSES:

District Engineer, U.S. Army Corps of Engineers, Los Angeles District, ATTN: CESPL-PD-RN (L. Young), PO Box 532711, Los Angeles, CA 90053-2325.

FOR FURTHER INFORMATION CONTACT:

Ms. Lisa Young, Environmental Coordinator, telephone (213) 452-3852, or Mr. Tony Risko, Chief, Coastal Studies, Group, telephone (213) 452-3833.

SUPPLEMENTARY INFORMATION:

1. Authorization

This Feasibility Study was authorized by the House Public Works and Transportation Committee Resolution adopted April 30, 1992 which states: “Resolved by the Committee on Public Works and Transportation of the Unites States House of Representatives, that in accordance with Section 110 of the River and Harbor Act of 1962, the Secretary of the Army, acting through the Chief of Engineers, is requested to investigate the feasibility of providing shore protection improvements along the shores of the City of Oceanside, San Diego County, California, in the interest of shoreline protection and storm damage reduction and other related purposes.”

2. Background

During the 1880's Oceanside Beach was approximately 90 meters wide. This shoreline width was further advanced in the floods of 1889, 1891, and 1916 bringing large volumes of sediment from the San Luis Rey and Santa Margarita Rivers. The City used the widened beach as a resource, and in 1927 a recreational pier, beachfront, strand, parking lots and houses were constructed in front of the seacliff. During this period a dam was also constructed on the San Luis Rey River to control flooding. At the start of the U.S. involvement in World War II, the U.S. Marine Corps designed and contracted construction of a small boat basin in a narrow lagoon between the Santa Margarita and San Luis Rey Rivers to support an amphibious training base. This included four jetties, which were later extended. Another dam was constructed on the Santa Margarita River to control flooding in 1949.

The presence of the coastal structures, such as jetties and breakwaters, has resulted in the disruption of sediment transport, creating a variety of localized shoreline effects. Sediment tends to accumulate at the beach north of the harbor, within the harbor entrance, and south of the harbor south jetty. However, erosion tends to occur downcoast of the labor. Damages reported by residents consist mainly of inundation damages and damages to revetment. These damages occur when storm wave conditions coincident with high tidal elevations or storm surge causes an elevated sea surface and higher wave run-up elevation. The majority of damages in Oceanside occurred during storms in 1977-1978, 1982-83, 1988, 1993-1994, and 1997-1998. In addition to high waves and water surface elevations, damage is intensified by shoreline erosion and beach retreat. Oceanside has historically experienced a narrow beach, but has recently undergone accelerated erosion. A large volume of material has been placed back on the beach during construction and maintenance dredging, but a deficit in sand for the beach still exists. The average recession of Oceanside Beach from 1940-1999 is approximately 60 meters or 1.1 m/yr. In 1974, the USACE issued a position paper on beach erosion that tentatively indicated that the harbor was the primary cause of erosion.

3. Alternatives

The Feasibility Study will focus on the problems and needs caused by beach erosion. In general, alternative plans will focus on reducing the beach erosion and improving sand accumulation through either construction or management project features such as groins, reefs, and/or dredge and disposal. Other features may include coordinated environmental enhancement of the lagoons or river mouths in the project area.

The primary undesirable impacts of concern from any of the alternatives will likely be related to temporary turbidity and displacement of sand dwelling organisms and their predators. These will be addressed in the study as part of the plan formulation of the Feasibility Study, and potential impacts will be analyzed in the DEIS.

4. Scoping Process

Participation of all interested Federal, State, and County agencies, groups with environmental interests, and any interested individuals is encouraged. Public involvement will be most beneficial and worthwhile in identifying the scope of pertinent, significant environmental issues to be addressed; identifying and eliminating from detailed study issues that are not significant; offering useful information such as published or unpublished data; providing direct personal experience or knowledge which informs decision making; and recommending suitable mitigation measures to offset potential impacts from the proposed action or alternatives.

5. Public Scoping Meeting

The specific date, location, and time of the public scoping meeting will be announced in the local news media at least two weeks prior to the meeting. A separate notice of this meeting will be sent to all parties on the study mailing list. The purpose of the scoping meeting will be to gather information from the general public or interested organizations about issues and concerns that they would like to see addressed in the DEIS. Comments may be delivered in writing or verbally at the meeting or sent in writing to the Los Angeles District at the address given above.