Restoring natural characteristics of a Southern California wetland.
San Elijo Lagoon Ecological Reserve is transitioning from open water and mudflat habitats to salt marsh and riparian habitat as a result of urban pressures. Highways, a railroad, and nearby infrastructure all contribute to restricted tidal flushing and degraded water quality in the reserve.
As population expands in Southern California, the ecology of the wetland will continue to be impacted by both historical and future development.
There is a long-range plan under way to restore the lagoon to a more natural state. San Elijo Lagoon is a biodiversity hot spot, one of few remaining wetlands in Southern California. The 915–acre reserve hosts more than 700 species of plants and animals, many rare and endangered. Seven miles of trails for hiking, bird watching, and wildlife photography offer people a natural environment for solace and inspiration.
San Elijo Lagoon Restoration Project Goal
The San Elijo Lagoon Restoration Project (SELRP) will restore and maintain San Elijo Lagoon Ecological Reserve to perpetuate native plants and animals characteristic of Southern California, as well as to restore and maintain estuarine and brackish tidal flushing.
The reserve is located within the City of Encinitas, and is owned and managed by California Department of Fish and Game, County of San Diego Department of Parks and Recreation, and San Elijo Lagoon Conservancy.
San Elijo Lagoon Conservancy, project stakeholders, and sponsors California State Coastal Conservancy and San Diego Association of Governments (SANDAG) are working together to address the restoration of San Elijo Lagoon.
The Need for Lagoon Restoration
Over the past several decades, the ecological system has gradually degraded:
- Urban development has altered the hydrology and increased sedimentation within the lagoon.
- Urban runoff affects habitat type and quality. Mechanical breaching of the ocean inlet is routinely performed to maintain tidal flushing within the lagoon. However, sedimentation has reduced open water and functional tidal mudflats.
- Invasive plants proliferate in muted tidal conditions and increased sedimentation. Plants such as the freshwater cattail block tidal channels and impact lagoon hydrology and tidal exchange. The expansion of two key species, cordgrass (Spartina spp.) and pickleweed (Sarcoconia pacifica), has been documented through focused vegetation mapping performed by SELC from 2001 through 2008. Changes in species will continue if no restoration occurs, speeding the transition of the lagoon from open water and mudflat habitats to salt marsh and riparian habitat.
San Elijo Lagoon Restoration Project Objectives
1. Physical restoration of lagoon estuarine hydrologic functions
- Open the lagoon mouth regularly, or create a permanently open mouth, to enhance the health and ecological value of the lagoon.
- Enlarge the tidal prism to increase area of tidal expression within the lagoon and manage freshwater inputs.
- Improve water quality through restored tidal circulation, thereby reducing impacts to the public from beach closures due to high bacteria counts and the potential for mosquito- borne disease.
- Ensure no adverse change to current flood protection, specifically to existing infrastructure and adjacent development.
- Minimize the disturbance of cultural resources.
2. Biological restoration of habitat and species within the lagoon
- Provide a natural gradient of habitats that considers climate change, anticipated sea level rise, heterogeneity of habitats, and tidal channels of various orders.
- Enhance habitats for native species, including rare and endangered species, to maintain species diversity appropriate to habitat distribution and regional conservation efforts.
3. Management and maintenance to ensure long-term viability of the restoration efforts
- Develop a cost-effective management and maintenance plan for supporting the proposed habitat enhancements, curtailing growth and expansion of exotic species, and maintaining regular tidal flow.
- Design and implement a biological and hydrological monitoring program to assess the success of restoration efforts and facilitate adaptive management decisions.
- Maintain lagoon public access and educational opportunities consistent with resource protection needs and requirements.
Next Steps: Combined EIS/EIR
Given the project complexity and range of potentially significant issues, the appropriate environmental document will be a combined Environmental Impact Statement (EIS)/ Environmental Impact Report (EIR).
The environmental review and permitting process will involve many of the stakeholders. Because of both federal and state discretionary actions, the SELRP will be evaluated pursuant to the federal National Environmental Policy Act (NEPA) and the California Environmental Quality Act (CEQA).
As an essential component of the implementation, maintenance and monitoring endowment will be a part of the final restoration plan. The endowment will provide funds to ensure that tidal connection remains open to the ocean, which will ensure tidal flushing in the East Basin, as well as adaptive management for sea level rise and the availability of transitional habitats, and operations, maintenance and monitoring within the boundaries of the project.
Historical Wetland Loss
Nearly 90% of Southern California’s wetlands were developed or severely degraded in the decades prior to the 1980s. This was a time when the draining and destruction of wetlands was considered acceptable in permitting, an inevitable part of development. Many wetlands were drained to support agricultural uses, while others were filled for urban development, diked for water impoundments or to diminish flooding, or dredged for marinas and ports. Indirect impacts from pollutants, urban runoff, and invasion by non-native species continue to degrade and destroy wetlands.
A number of state and federal agencies, wetland conservation groups, and nonprofit organizations have been allocating resources to wetland restoration throughout the state. This is particularly applicable to coastal systems in the densely-populated San Diego region. To determine the most appropriate post-restoration lagoon structure and function, a variety of factors can be considered: including historic conditions, maximization of regional habitat diversity, plant and animal species requirements, maintenance variables, public preference, etc.
Thousands of years ago, San Elijo Lagoon was an embayment, meaning incoming tides reached the current La Bajada Bridge in Rancho Santa Fe. San Elijo Lagoon is the terminus of the 77- square mile Escondido Watershed as it drains into the ocean. Because of urban density, and transportation infrastructure traversing the lagoon, tidal circulation has been severely restricted, leading to beach closures and elevated bacteria levels.
- 1912: Pacific Coast Highway opened
- 1925: Railroad Berm constructed
- 1930s: A series of dikes and levees were constructed.
- 1965: Interstate 5 opened, constricting hydrology between Central and East Basins
- 1980s: Concrete dike built that crossed the East Basin to create habitat for migratory waterfowl.
These hydraulic barriers, along with development adjacent to the lagoon and upstream, have severely restricted the natural tidal prism, leading to a consistent degradation of water quality in the lagoon and the Pacific Ocean adjacent to the lagoon mouth.
History of SELRP Project Planning
The SELRP project is the culmination of 23 years of planning for the restoration of the Lagoon’s ecological systems.
The San Elijo Lagoon Enhancement Plan (1996) served as the original baseline, recording the then-current condition of the lagoon and laying out a long-term plan for restoration of a threatened wetland. At that time, there was no funding for an Environmental Impact Report (EIR)—a legal prerequisite for all large scale projects with potential environmental consequences.
In 1996, San Elijo Lagoon Conservancy began to create small, proactive habitat management projects in San Elijo Lagoon. The end result was the San Elijo Lagoon Action Plan (1998), which was further refined in the Escondido Creek Watershed Restoration Action Strategy (2005) that addressed restoration of the entire Escondido Creek watershed.
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