Diamond Bar housing element map

2013 General Plan Housing Update Map

The areas circled in red, including the trails around Diamond Bar Center, were designated as "open space" during that process.

Then in 2014, based upon the new Housing Area Map, the city updated its zoning.

As you can see below, the new zoning map did not look anything like the Housing Update map designations. Larger Version.

Diamond Bar housing element map

Diamond Bar Current Zoning Map, updated 2014

All the open space designations disappeared and were replaced with zoning for residential housing. See the larger map here.

It remains the case that all of our natural open space is still zoned for housing.

Then, in 2016 Diamond Bar began working on a new General Plan.

Now we're seriously concerned a about the Diamond Bar Center Trail area.

The new General Plan's proposed language, states that the 450 acres of Diamond Bar Center trails will be "preserved in perpetuity."

But, notice the General Plan's Existing Parks, Open Space, and Recreation Facilities map below.

Diamond Bar Existing Parks map

Existing Parks, Open Space, and Recreation Facilities Map for new General Plan

Notice that Diamond Bar Center Trail area is designated only as a "Vacant Natural Area", not open space.

This seems odd, since the area around Trigger Lane in the lower left is designated as Open Space/Greenways/Trails

Here's the question: if the Diamond Bar Center trail area is to be protected in perpetuity, why isn't it also designated as open space? See the larger map here.

It gets even more interesting.

Diamond Bar Land Use Planning map

City of Diamond Bar General Plan Land Use Map

Notice that the Diamond Bar Center trails are now designated as a "Planning area."

While, once again, the Trigger Lane area in the lower left corner is designated as Open Space. See the larger map here.

A Planning Area is natural land designated for development.

According to proposed General Plan language, a Planning Area: "...is applied to properties where creative approaches are needed to integrate future development with existing natural resources."

The General Plan Document which defines a Planning Area can be found here. It mentions Government Code 65450. The specific language of that statue can be found here.

Bottom line: There are no constraints on natural open space development in these areas.

Diamond Bar Steep Slopes map

City of Diamond Bar Steep Slopes Map

Notice the natural open spaces designated for housing all have slopes over 30 percent

This means that any development of natural open spaces will require significant grading and the resulting destruction of ridgelines and native habitat. See the larger map here.

Diamond Bar's rugged topology already limits residents' ability to evacuate during an emergency.

Soils in these areas are also subject to landslides and liquefaction, during earthquakes.

We believe the ecological benefits of leaving these spaces open far outweighs the risks of developing them.

Diamond Bar Fire Risk map

City of Diamond Bar Fire Hazard Map

Notice that most of the natural open space areas are also in Very High fire risk areas.

Given the fire danger for housing built in these areas and all the risks mentioned above, we question the wisdom of even considering developing these natural open spaces. See the larger map here.

Global Bio Diversity Map

Global Hot Spots of Biodiversity Map

Scientists have designated 20 worldwide “Hot Spots.” These are places rich in species diversity, yet are threatened by imminent development. The Puente-Chino Hills Wildlife Corridor is situated in one of these Hot Spots. This Hot Spot is an area second only to tropical rain forests in both diversity of species and threat. Larger Version.

City of Industry Map

City of Industry Map

This map shows the City of Industry ownership within the Puente-Chino Hills Wildlife Corridor. Larger Version.