Walnut Creek Habitat and Open Space







The Walnut Creek Habitat and Open Space is a combined total of 60.9 acres of oak and walnut woodlands, coastal sage scrub, and access to Walnut Creek riparian areas in unincorporated Los Angeles County and adjacent to San Dimas’s Loma Vista neighborhood park. The site offers the opportunity for riparian and upland habitat enhancement and trails with quality vistas of San Gabriel Mountains National Monument and connection to the Antonovich multi-purpose trail system.


Our Plans

A Conceptual Master Plan adopted by the WCA identified the predominant public use activity for this property as passive recreation that highlighted the existing natural landscape. The plan includes development of educational and interpretive features to inform visitors about the native California environment and cultural resources. The plan further lays out the management of invasive plants and re-vegetation with native species.



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Initial West Phase Development

An initial West Phase is currently being planned. It is proposed to include site clean-up, passive recreational elements, habitat enhancements, and the planting of a vegetated screening buffer. This phase will accomplish the necessary improvements to provide public access over a portion of the Project Site. As identified in the attached Exhibit B, recreational elements include trail development and trail-side amenities (interpretive signage, benches, etc.) that will create a looped spur trail connection to the existing LA County Antonovich Trail. Public access will only be made from the Antonovich Trail, accessible from four nearby County-operated trail staging areas. Site clean-up includes removal of buildings from a portion of the Project Site under City ownership.


Property Overview

Today this area is a critical wildlife corridor for species moving between Bonelli Regional Park along Walnut Creek towards the San Gabriel River. It is also formally of home of the Voorhis Campus, a school for underprivileged boys foundaed in 1927. In 1938, the property was donated and the school became a unit of CalPoly Pomona until 1956 when severe overcrowding at the San Dimas campus caused the agricultural and landscape architecture programs to be moved to the current Cal Poly campus site, formerly property of the Kellogg Ranch.

The original Voorhis campus was situated on 145 acres of oak-dotted hills and mesa and was eventually sold to the Pacific Coast Bible College before being split with roughly 2/3 of the original acreage currently owned by the Tzu Chi Foundation, an education and international humanitarian relief organization that provides low cost medical care and educational programs to disadvantaged communities in the San Gabriel Valley. The remaining 1/3 of the original acreage is the property now owned by the Watershed Conservation Authority and City of San Dimas.

A few of the original campus buildings remaining on the park property may find re-use opportunities in the park. Like all of our park properties, the WCA’s goal is to create a project that will be a model for sustainable, multi-benefit watershed projects that address the open space recreation and watershed needs of the region.



The first step in development of the park will be the construction of a trail connection to the Antonovich Trail and implementation of a riparian buffer between the park and residents.  



Downloads (PDFs)

Conceptual Master Plan Report

West Phase Conceptual Plan

Initial Study & Mitigated Negative Declaration (IS/MND)

IS/MND Appendix A: Site Assessment Report

IS/MND Appendix B: Concept Development Report

IS/MND Appendix C: Biological Constraints Analysis

IS/MND Appendix D: Jurisdictional Delineation Report

IS/MNDAppendix E: Phase I Cultural Resources Report

IS/MND Appendix F: Geotechnical Feasibility Evaluation

IS/MND Appendix G: Hydrological Investigation

IS/MNDAppendix H: Traffic Evaluation

Section 7 Mitigation Monitoring Program