Specific Land

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Tres Hermanos is important, but two additional large tracts of land need saving as well.

Saving these 9,000 acres will create an unprecidented legacy, a gift of sanity to ourselves, and our region's future.

This sprawling collection of properties forms a large, unprotected wildlife corridor which provides habitat and transit for many threatened and endangered species.

There are numerous scientific reasons for saving this land. (Read More, and more here.) But there is another very important reason we haven't discussed, yet.  Known as the "Missing Middle," these three properties create a link between 13,000 acres in Chino Hills State Park and  4,000 acres of preserved open space in Whittier.

"When complete, this phenomenal corridor will serve as a lifeline for wildlife, a place of recreation, and retreat for the residents of the region. The trails and pathways will extend from the San Gabriel River in Los Angeles County on the west to Temecula in San Diego County on the southeast. Imagine what a gift to the future this could be – a linkage of natural lands in one of the most highly urbanized regions of the world."  

Concerned citizens have been working on creating this corridor for the last over 30 years. You can help too. Volunteer or Donate.

In the map below, you can see how the three properties fit into, and create the "missing middle" of the wildlife corridor.
... Read more.

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Each individual property presents its own unique challenge:

We begin with Tres Hermanos

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The 2445 acres of Tres Hermanos are located partly in Los Angeles County and partly in San Bernardino County.  Approximately 695 of these acres are located in the city of Diamond Bar, in eastern Los Angeles County and pproximately 1750 of these acres are located in the city of Chino Hills, in south western San Bernardino County.  

Tres Hermanos has a colorful recent history.  Originally part of a Spanish land grant, it was owned by the powerful Los Angeles Times Chandler family.  Most recently, in the 1970's it was purchased by City of Industry and has had its share of failed plans.  City of Industry originally envisioned it to be part of a water pumping plan (see below).  Their latest plan was to install a huge solar farm on it, a plan which resulted in multiple law suits, criminal investigations, and interesting political drama.

Finally, in February of 2019, the three cities, City of Industry, Diamond Bar and Chino Hills came to a settlement agreement.  They recreated the Tres Hermanos Conservation Authority, and made it the ranch's owner, with the restriction of limiting the land to "open space, public use or preservation."  The three cities now jointly manage the Conservation Authority.

Click here for a more detailed explanation of the Tres Hermanos Conservation Authority creation process and a link to the creation documents.  

That said, both Chino Hills and Diamond Bar currently have development zoning on Tres Hermanos, and Diamond Bar has it designated as a general plan "planning area," which is a code name meaning "open for development". 

We applaud the three cities for setting aside their differences and working together to create the Conservation Authority.  We now urge them to take the next steps forward toward truly saving this important historical site and designating it as protected natural open space.

Industry's Tonner Canyon Property

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City of Industry purchased this land with the intention of creating a huge resevoir which would reach up into Tres Hermanos.  Their plan included several dams, which would allow them to pump water into Upper Tonner Canyon (Tres Hermanos) during the evening hours, when electricity rates were cheap.  During daytime hours, they planned to bring the water back down to Lower Tonner Canyon, generating electricity for a profit when rates were higher. Fortunately, that plan was never realized and luckily, other plans like a solar farm were never realized either. 

This pristine, undeveloped, biologically diverse property is part of Los Angeles County Sensitive Ecological Area 15.  Los Angeles County recently strengthened development requirements for their Sensitive Ecological Areas, which, combined with the steep, hilly topograpy, would make development here difficult.

This land, as one can see from the Hills for Everyone Map above, is a critical link in the creation of the wildlife's corridor's "Missing Middle."  

We say leave the few precious hills we have left intact, and save this land as natural open space for posterity.

Shell Aera

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The nearly 3,000 acres of the Shell Aera property extend from beyond Harbor Blvd in the west, past the 57 freeway to the east.  Oil wells on this Shell Aera property are nearing the end of their production life.  

Shell Aera had ambitious plans for this property once the oil wells ran dry.  Their ecologically disasterous plan was to bulldoze the property's hills essentially flat, requiring the relocation of over 50 million cubic yards of soil.  Then they planned to build 3,600 houses along with 300,000 square feet of retail space on the geologically unstable land, with the main exit from the development connecting to Brea Canyon Rd.  In case of a fire or emergency, safe evacuation would have been impossible.

Portions of this area are also part of Los Angeles County Sensitive Ecological Area 15. After Los Angeles County strengthened the development requirements for its Sensitive Ecological Areas, Shell Aera recently withdrew its development plan.  

This huge parcel is also a critical part of the wildlife corridor's "Missing Middle." Other conservation organizations such as Hills for Everyone have been attempting to purchase this land for years in an effort to save it as natural open space.

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You've seen Tres Hermanos on the video. Here one can see the hills Aera planned to flatten on the left of the 57 freeway.  On the right of the freeway we can see a portion of City of Industry's property.  All these hills deserved to be saved.