Walnut Creek Habitat and Open Space







The Walnut Creek Habitat and Open Space protects 60.9 acres of land containing oak and walnut woodlands, coastal sage scrub, and public access to Walnut Creek riparian areas in unincorporated Los Angeles County adjacent to San Dimas. Walnut Creek Habitat and Open Space was originally envisioned to be to continuous with the City of San Dimas's Loma Vista neighborhood park.

WCA's newly restored Walnut Creek Nature Loop Trail connects to the Antonovich multi-purpose trail system and offers vistas of the San Gabriel Mountains National Monument. The Walnut Creek Nature Loop trail features habitat restoration, benches, and interpretive features highlighting California ecology. 

In 2023, WCA and the neighboring Tzu Chi Foundation completed a lot line adjustment to ensure protection of the connection between the Walnut Creek Habitat and Open Space to the County-maintained Antonovich trail in perpetuity. This lot line adjustment will also allow WCA to rehabilitate continuous habitat from the Walnut Creek stream corridor to upland coastal sage scrub.


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 founded 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.





Downloads (PDFs)

Conceptual Master Plan Report

West Phase Conceptual Plan

Initial Study & Mitigated Negative Declaration (IS/MND)

IS/MND Appendix A: Site Assessment Report Part 1

IS/MND Appendix A: Site Assessment Report Part 2

IS/MND Appendix C: Biological Constraints Analysis

IS/MND Appendix D: Jurisdictional Delineation Report

IS/MND Appendix E: Phase I Cultural Resources Report

IS/MND Appendix F: Geotechnical Feasibility Evaluation

IS/MND Appendix G: Hydrological Investigation

IS/MND Appendix H: Traffic Evaluation

Section 7 Mitigation Monitoring Program