IMPORTANT UPDATE:
For information about removal of citrus trees on flood control property, see Citrus Orchard section below.
Where is the Santa Ana River Canyon Habitat Area?
The Santa Ana River Canyon Habitat Area is comprised of approximately 1,100 acres of canyon habitat along the Santa Ana River from downstream of Prado Dam to Weir Canyon Road.
What is the Habitat Management Plan?
The Santa Ana River Canyon Habitat Management Plan (HMP) was developed in 2009 as a requirement of the Santa Ana River Mainstem Project (SARMP). The HMP addresses mitigation of impacts on the floodplain and open space wildlife habitat in the Santa Ana Canyon downstream of Prado Dam.
The HMP includes:
• Preservation and maintenance of the existing habitat at the time of plan adoption
• Recommendations for future habitat enhancement, and;
• Protection of recreational components within the Habitat Management Area (HMA)
The primary objectives of the HMP are to:
1. Develop a plan for the management of floodplain habitat to be reserved as open space.
This is in accordance with the requirements of the Local Cooperation Agreement (LCA) between the US Army Corps of Engineers and the SARMP local sponsors, which include the Orange County Flood Control District (OCFCD), Riverside County Flood Control and Water Conservation District, and San Bernardino County Flood Control District.
2. Identify the HMA and its resources as required by the SARP Phase II General Design Memorandum Final Supplemental Environmental Impact Statement (FSEIS) and the Local Cooperation Agreement (LCA).
3. Identify various activities permitted within the HMA.
4. Identify maintenance standards and responsibilities, and;
5. Identify existing uses within the floodplain and any operational constraints posed by existing uses.
Citrus Orchard within the HMA
In 1987, the Orange County Flood Control District (OCFCD), as part of a 240-acre purchase from land developer CW Associates, acquired a 21-acre citrus orchard, located along the Santa Ana River floodplain in the city of Yorba Linda within the HMA. The area remains under the ownership of the OCFCD for flood control purposes.
Detection of Huanglongbing (HLB) Disease at Citrus Orchard on OCFCD Property
On October 21, 2024, California Department of Food and Agriculture (CDFA) confirmed the presence of 53 Huanglongbing (HLB)-positive trees within the orchard. HLB is carried and spread by a tiny insect called the Asian citrus psyllid (ACP). The orchard is located within an established ACP and HLB State Interior Quarantine zone.
Why Were the Citrus Trees at the Orchard Removed?
Initially, CDFA designated the 53 HLB-infected trees a public nuisance and issued an order to treat and remove the infected trees within 72 hours upon receipt of notice to prevent the spread of the HLB disease. Under emergency action, OC Public Works utilized a private contractor to remove all citrus trees from the orchard to prevent the spread of ACP and HLB and reduce potential impact to residential citrus trees and commercial citrus production throughout the region.
Steps to Safely Remove Infected Trees:
• October 2024: OC Public Works retained the services of West Coast Arborists, Inc., (WCA) which promptly treated and removed the 53 HLB-infected trees within the required 72-hour period. Additional surrounding trees were then tested as required by protocol.
• November 1, 2024: CDFA issued an order for two treatments for the remaining citrus trees in the orchard to suppress the ACP population. OC Public Works retained the services of TruGreen, a CDFA-recommended contractor, for insecticide treatment for a majority of the orchard (Parcels 1 and 2) that had available access. Subsequently, crews were able to create safe access to the remaining area of the infected orchard (Parcel 3), which facilitated the treatment of the entire orchard.
• November 18, 2024: CDFA confirmed the presence of 33 additional HLB-positive trees in the orchard, also requiring their treatment and removal within 72 hours. WCA completed the work within the required period. Additional samples from surrounding trees were collected for testing upon the removal of the 33 HLB infected trees as required by the protocol.
• Mid-December 2024 to early January 2025: Removal of remaining citrus trees. This work was substantially complete as of January 6, 2025.
• January 14, 2025: CDFA confirmed all required steps were completed to mitigate the pest risk, including treatment and tree removal.
• Nearby residential properties: Along with the treatment and removal of the infected trees from the site, CDFA will be conducting surveys, performing treatment and collecting samples on residential properties with HLB host plants located within 250 meters of the HLB site.
What Will Be Done on the Property Now that the Trees Have Been Removed?
The restoration of natural conditions will support native habitat, prevent further spread of the ACP and HLB, and avoid the use of resources for future treatments and removals required by regulatory agencies.
The existing habitat adjacent to the orchard currently supports the least Bell’s vireo, a federal and state endangered bird species. The US Fish and Wildlife Service (USFWS) and the California Department of Fish and Wildlife (CDFW) support efforts to remove man-altered habitats in favor of expanding native habitats within the HMA, with USFWS actively encouraging a land use change of the former orchard to restore habitat suitable for the least Bell’s vireo.
Additional Information About the Huanglongbing (HLB) Disease
The plant disease known as citrus HLB or citrus greening is a destructive disease affecting citrus worldwide. HLB is carried and spread by the Asian citrus psyllid (ACP). Fruit from infected trees is of no value because of poor size and quality. Once infected, the tree will eventually die, several months to a few years after infection.
In 2009, ACP was first detected in Orange County, triggering a quarantine to restrict movement of regulated plant material. The first confirmed case of HLB in Orange County was in April 2017. Currently, HLB quarantines have been established in portions of Los Angeles, Orange, Riverside, San Bernardino, San Diego and Ventura counties. More than 8,900 trees have tested positive for the disease and have been removed, including 5,006 trees at 3,167 residential properties in Orange County.
We will continue to work with CDFA to support pest detection, enforcement of quarantine and eradication efforts. Our goal is to protect Orange County’s agricultural industry and the ability for residents to grow and eat fresh fruits and vegetables free from exotic pests and diseases. We will work closely with impacted industries such as produce vendors, growers, and farmer’s markets to ensure they are aware of the quarantine requirements.
Residents with questions regarding this activity can contact the Orange County Agricultural Commissioner’s office at 714-955-0100 or CDFA’s Pest Hotline at 1-800-491-1899.
Additional information about HLB and the ACP can be found here: https://www.cdfa.ca.gov/citrus/pests_diseases/hlb/regulation.html
Santa Ana River Parkway Project within HMA
The County of Orange is proposing to extend and realign the Santa Ana River Bikeway and Riding and Hiking Trail to better serve users and to complete its portion of the proposed 100-mile recreational parkway adjacent to the Santa Ana River. The project site is located along the Santa Ana River Parkway between Gypsum Canyon Road and the Orange County Boundary.
• The Santa Ana River Parkway Project will extend the Santa Ana River Bikeway and the separate Santa Ana River Riding and Hiking Trail within this parkway.
• The Santa Ana River Bikeway is a regional Class I (off-road, paved) bikeway; it accommodates pedestrians and commuter and recreational bicyclists.
• The Santa Ana River Trail is a regional riding and hiking trail (unpaved); it accommodates walkers, hikers, runners, joggers, mountain bicyclists, and equestrians.
Currently the Orange County portion of the Santa Ana River Class I Bikeway extends 28 miles from the Pacific Ocean to the county boundary. The bikeway is adjacent to the Santa Ana River for most of this distance. The 26-mile Riding and Hiking Trail also begins near the Pacific Ocean and ends approximately 2 miles downstream of the Orange County boundary, at Gypsum Canyon Road in the city of Yorba Linda. Access to the Parkway is available from numerous public roadways which span the river, and from regional and local parks and trails.
Flood Control Improvements within the HMA
Flood control improvements within Santa Ana River between Prado Dam and Weir Canyon Road (known as Reach 9) include levee projects (Phase 1, 2A, 2B, 3, 4, 5A, 5B, BNSF, Mobile Home, BNSF) for the protection of the:
- SR-91 Freeway
- Green River Housing Estates
- Green River Mobile Home Park
- Green River Golf Course
- Residential and commercial establishments along La Palma Ave in the city of Yorba Linda and;
- Santa Ana River Interceptor (SARI) Line – a major sewer trunk line owned and operated by the Orange County Sanitation District and Santa Ana Watershed Project Authority.
Restoration, mitigation and conservation efforts for the Reach 9 improvements are included in the HMP and include native vegetation establishment.
