Colorado Substation Tree Removal

The Federal Energy Regulatory Commission provides standards and guidelines for the protection of critical utility infrastructure and recommends that substations be reviewed for security. In 2017, a security review was undertaken for this substation.  The recommendation was to remove vegetation within 10 to 20 feet of the fence.  In addition to the security issues, the trees at this location continuously drop needle debris within the substation and provide fuel for a fire started in the substation.

The City will mitigate the removals by planting trees in another location.

When will the tree removal begin?

A project timeline is currently being drafted.

Where are the trees being removed? 

The trees are being removed from the area adjacent to the substation fence.

Why are the trees being removed?

The trees are blocking the view from the street of the substation fence area as well as blocking camera surveillance along the exterior of the fence line. This increases the possibility of  an undetected breach of the substation fence. In addition, the trees drop large quantities of needles and other debris on the ground in the general area both inside and outside the substation.   The tree debris covers the insulating medium on the substation ground and exposes the Operations personnel to dangerous step potentials. Tree pollen coats the insulators of the energized equipment and must be regularly washed off to maintain electrical reliability. 

What risks are there for unauthorized entry to the substation?

This poses a risk due to sabotage or vandalism within the substation that could cause extensive long-term outages in the City.  In addition, unauthorized personnel within the substation are at risk to be seriously injured if they are unfamiliar with equipment within the substation.

Do electrical facilities get vandalized or sabotaged?

Yes. This particular substation was vandalized in February in the area that is behind the trees being removed. The substation fence was ignited and about 100 feet of the fence structure was burnt at the bottom of the fence before the Fire Department arrived and extinguished the fire. There have also been significant terrorist attacks on Bay Area electrical facilities. One of the larger events occurred at PG&Es substation located in South San Jose in 2013 where 17 high voltage transformers were shot at resulting in 12 Million dollars of damage. In 1990, 4 electrical support structures in Santa Cruz and the South Santa Clara County were destroyed by environmental terrorists.

Will there be mitigation for the trees being removed?

Trees will be planted at other locations within the city to compensate for the loss of these trees.

Will new trees be planted at the substation site?

Not at this time. This site is being evaluated for expansion of the substation foot print to allow for better access into and out of the substation. All the existing landscaping, with the exception of the trees, will remain in place until a plan is approved through the City’s building planning process.