Joint-use poles: whose vegetation obligation is it

The duty follows the facility, not the pole. GO 95 Rule 35 binds supply and communication companies alike: the Table 1 clearance belongs to the electric utility, and the strain and abrasion duty to whoever owns a circuit at 750 volts or less. PRC 4292 and 4293 reach only the owner of an electrical line.

Location 45 in the CPUC's 2024 audit of Comcast's South Bay region is a wood pole in Monterey County, logged at -121.92901476, 36.54205852. Staff wrote it up twice.

Once under GO 95 Rule 35, against Comcast, for a messenger cable rubbing vegetation. Once in the third-party table, for top branches pressing on the communications lines, branches that had already been cut free of the trunk and left lying in the span. The entity column on that second entry reads "Unknown."

One pole, one tree, two findings, and one company name between them. That is the joint-use question in its working form, and every rule in the stack answers it the same way: the duty does not attach to the pole. It attaches to the facility.

The pole the rules mean when they say joint use

GO 95 defines the term in Rule 21.8:

Joint Use of Poles or Poles Jointly Used means occupancy of poles or structures by circuits of different ownership or by two or more of the following classes of circuits of the same ownership: - Communications circuits for public use - Railway or trolley circuits - Supply circuits other than trolley circuits

Two things in that definition catch people. Different ownership is one route in, and the second clause supplies another: a pole carrying one company's supply circuit alongside its own public communications circuit is a joint-use pole. And the definition speaks to occupancy of the space. Ownership of the wood underneath is a separate fact, and it can be shared among parties who differ from the occupants.

The scale is ordinary rather than marginal. The CPUC's Policy and Planning Division reported in July 2014 that Southern California Edison stated 70 percent of its poles are jointly owned, and that the Northern California Joint Pole Association had 40 members. For most California distribution corridors, the shared pole is the base case.

GO 95's joint-pole section never mentions a tree

Section IX of GO 95 is titled "Joint Poles or Poles Jointly Used." It is the obvious place to look, and Rule 90 explains why the answer sits elsewhere:

The following rules cover certain details of construction on jointly used poles (see Rule 21.8 for definition of joint use of poles). These rules are additional to those contained in other sections, and the requirements of such other sections shall be followed in all respects except as modified herein.

Section IX modifies construction details. Rule 90 states the scope, and Rules 91 through 94 cover poles and structures, conductors and cables, climbing space, and antennas. In the December 2024 edition of the General Order, Rules 90 through 94 use the words vegetation, tree and trimming zero times.

So the vegetation answer for a shared pole comes out of the rules that apply to all lines, Rule 35 and Rule 18, and both of those are written company by company and facility by facility.

Rule 35 binds both companies and gives them different work

Rule 35 settles its own reach in one sentence at the end of its first paragraph:

These requirements apply to all overhead electrical supply and communication facilities that are covered by this General Order, including facilities on lands owned and maintained by California state and local agencies.

A communications attacher is inside Rule 35. What it is inside Rule 35 for is the part that gets missed, because the rule's three paragraphs hand out three different duties.

The first paragraph sets the Table 1, Cases 13 and 14 clearances. Both cases are written for bare line conductors, so the numeric clearance lands on the supply conductors overhead. The second paragraph is the dead, rotten and diseased overhang duty, and it names "a supply or communication company" as the holder. The third paragraph is the one a cable company actually gets cited under:

When a supply or communication company has actual knowledge, obtained either through normal operating practices or notification to the company, that its circuit energized at 750 volts or less shows strain or evidences abrasion from vegetation contact, the condition shall be corrected by reducing conductor tension, rearranging or replacing the conductor, pruning the vegetation, or placing mechanical protection on the conductor(s).

Read the possessive. The duty runs to "its circuit." A communications cable is a circuit energized at 750 volts or less, so the attacher holds the strain and abrasion condition on its own plant, and the electric utility's clearance program leaves that condition open. What strain and abrasion mean, and why contact by itself does not constitute a nonconformance, the rule defines for itself.

That is how Comcast ended up with two Rule 35 findings in audit CA2024-1230, signed by Rickey Tse on September 20, 2024 after a field week that ran July 22 through July 26. Location 45: "Messenger cable rubbing vegetation." Location 46: "Vegetation pushing on span." Both findings sit on Comcast's own cable, and Comcast's own program is what closes them.

Appendix I answers the question column by column

The Commission has already worked through the two-company case in writing. Appendix I of GO 95, added by Decision 18-05-042 on May 31, 2018, gives illustrative priority levels for Rule 18 in two columns, one headed Electric and one headed Communications. Its preamble states the design intent:

Furthermore, the same condition may give rise to different safety or reliability concerns, depending on whether the facility at issue is a communications facility or an electric facility. Consequently, conditions may be classified in more than one level as described in this Appendix.

Here is the whole vegetation row of that appendix, set side by side.

Priority	Electric column	Communications column
Level 1	Vegetation contacting or nearly contacting high voltage conductor; vegetation contacting low voltage conductor and compromising structure	Vegetation contacting cable conductor and compromising structure
Level 2	Vegetation causing strain or abrasion on low voltage conductor	Vegetation causing strain or abrasion on cable
Level 3	none listed	none listed
Safety Hazard	Vegetation contacting or arcing to high voltage conductor; vegetation contacting low voltage conductor and compromising structure or conductor	Vegetation contacting cable and compromising structure or cable

Three things fall out of that table on a shared pole.

Proximity to a high voltage conductor is a Level 1 condition that lives entirely in the electric column, because high voltage belongs to the party overhead. Contact with a cable rises above Level 2 once it is "compromising structure or cable," so a branch resting on a messenger is a different finding from a branch resting on a primary. And every vegetation example in the appendix sits at Level 2 or higher, which keeps all of them clear of the 60 month window that Level 3 allows.

The correction clocks behind those levels are set in Rule 18-B(1), and the Level 2 ceilings run short wherever fire risk is in play:

• six months for a potential violation creating a fire risk in Tier 3 of the High Fire-Threat District;

• 12 months for one creating a fire risk in Tier 2;

• 12 months for one that compromises worker safety;

• 36 months for all other Level 2 potential violations.

A Level 1 condition is corrected immediately. The same audit shows what a program looks like when those clocks slip. Comcast's South Bay records for May 2019 through May 2024 held 2,069 late work orders out of 69,835, of which 1,570 were Level 1. The most overdue was a Level 1 condition at 14381 Elva Ave 95070, inspected April 1, 2022, due April 2, 2022, and 616 days late. The deficiency description reads: "HVY TT (HEAVY TREE TRIMMING, TREES PULLING DOWN CABLE BUNDLE?)."

The notice, and the two clocks on it

Rule 18 was reorganized by Decision 18-05-042 with an implementation date of June 30, 2019, and the lettering changed in a way that still trips citations. In the current text, Rule 18-A is resolution and notification, and Rule 18-B is maintenance programs. Anything citing 18A for the auditable maintenance program is quoting the pre-2019 arrangement.

Rule 18-A covers three different notice situations, and a joint-use reader needs all three:

• 18-A(2): Company A's actions put Company B's facility in potential violation. Company B's entire remedial action is to send Company A a single documented notice, within 180 days of discovery, or within 10 business days if the condition is a Safety Hazard.

• 18-A(3): a company inspecting its own facilities finds a Safety Hazard on or near another company's facility. It notifies that company no later than 10 business days after discovery.

• 18-A(4): the owner or operator is undetermined.

That third case decides how a vegetation finding travels on a pole with three or four occupants:

To the extent a company that has a notification requirement under (2) or (3) above cannot determine the facility owner/operator, it shall contact the pole owner(s) within ten (10) business days if the subject of the notification is a Safety Hazard, or otherwise within a reasonable amount of time not to exceed 180 days after discovery. The notified pole owner(s) shall be responsible for promptly (normally not to exceed five business days) notifying the company owning/operating the facility if the subject of the notification is a Safety Hazard, or otherwise within a reasonable amount of time not to exceed 180 days, after being notified of the potential violation of GO 95.

The pole owner is a relay with a five business day service level. A note under the rule tells it what it must be able to look up: every other pole owner on poles it owns, and every authorized entity attached to its portion of a pole.

Rule 18-A(5) then decides how long the paper lives. Documentation of the notice is kept for at least 10 years by both the notifying and the receiving parties. Documentation of the correction is kept by the receiving party. So a notice sent and forgotten sits in the sender's file a decade later, ready to be matched against whatever was corrected.

Table 15 of the Comcast audit is what that file looks like in practice: 36 third-party observations across 32 pole locations, 21 attributed to AT&T, 7 to PG&E, and 8 to Unknown. Seven of the 36 concern vegetation. Comcast created and sent the notifications while staff were still in the field.

You cannot notify an owner the pole does not name

Eight Unknown entries in a 36 row table is Rule 91.5 working exactly as written.

Each communication cable and conductor as defined by Rules 20.4, 20.6(A), 20.9, 84.1, 87.4(C), and 89.1 that is attached to a joint-use pole shall be marked as to ownership. The marker shall (1) identify the owner of the cable and/or conductor; (2) provide a 24 hour contact number for emergencies or information; (3) be made of weather and corrosion resistant material; and (4) be clearly visible to workers who climb the pole or ascend by mechanical means.

Then the sentence that governs how much of the system carries a tag:

This marking requirement applies only to (A) new construction, (B) reconstruction of facilities, and (C) existing aerial communication cables and conductors that a technician works on when the technician ascends the joint-use pole for regular maintenance.

The rule arrived with Decision 12-01-032 in January 2012, and it reaches existing plant through the third clause alone, one climb at a time. A span last ascended in 2011 still carries whatever marking it had then, which on a lot of plant is none. When a crew finds a branch lying on an unmarked cable, the tag that would have closed the question is absent by design, and Rule 18-A(4) is the designed fallback: send it to the pole owner and start the five day relay.

The practical consequence for a vegetation program is that the pole inventory, rather than the tree inventory, sets how fast a finding reaches the party who can fix it. A finding that names a species, a diameter and a coordinate still has to be routed by somebody else until it names an owner.

The Public Resources Code never reaches the attacher

On State Responsibility Area land the same shared pole sits under two Public Resources Code sections, and both stop at the electric facility. They get there by different routes, which is worth knowing because the two routes fail differently.

PRC 4292 names communication circuits in an exclusion sentence, removing any line "used exclusively as telephone, telegraph" and the other categories the firebreak statute lists. The load-bearing word there is "exclusively." The 2021 California Power Line Fire Prevention Field Guide works the example: a railroad circuit used primarily for communication that also carries more than 750 volts to operate track switches stays subject to the statute.

PRC 4293 reaches the same result through its opening clause instead. Its duty falls on "any person that owns, controls, operates, or maintains any electrical transmission or distribution line," and its clearance bands are keyed to operating voltage beginning at 2,400 volts. A communications attacher owns a communications line and operates below the lowest band, so the statute passes over it twice.

Two consequences follow on a shared pole in an SRA. The ten foot firebreak around a subject pole is the electric utility's obligation alone, and the cylinder it describes contains the attacher's risers, ground wires and pedestals whatever the attacher's role in the work. And a CAL FIRE inspector finding brush at the base of a jointly used pole has one party to write up, whoever owns the hardware standing in it.

Inspection: two orders, and a pole that catches its neighbor's schedule

GO 95 Rule 31.2 splits the inspection duty in a few words each:

A. Communication Lines (See Rule 80.1) B. Supply Lines shall be inspected in compliance with the requirements of General Order 165.

GO 165 confirms the split from its own side, stating that it "does not apply to facilities of communication infrastructure providers." So the conductor and the cable on one pole run on separate inspection programs with separate definitions, separate intervals and separate record contents. Which four clocks that produces, and where the two orders define patrol and detailed differently, is its own subject.

One rule crosses the line in the other direction, and it is the only place in the stack where a pole's obligations turn on what its neighbor carries. Rule 80.1-B:

Wood poles in Tier 3 of the High Fire-Threat District that support only Communication Lines or equipment shall be intrusively inspected in accordance with the schedule established in General Order 165 if they are: - Interset between joint-use poles supporting supply lines in Southern California. - Within three spans of a joint-use pole supporting supply lines in Southern California. - Within one span of a joint-use pole supporting supply lines in Northern California.

The rule then defines Southern California as eight named counties and Northern California as all other counties in the state. So a communications-only pole in Tier 3, sitting two spans from a joint-use supply pole, is on a GO 165 intrusive schedule in Ventura County and off it in Sonoma County, on identical facts.

For a vegetation program the implication is procedural rather than arboricultural. Span proximity to supply is a mapped attribute that changes obligations. The corridor map therefore has to record which poles carry supply and which carry communications alone, at span resolution, before anyone can say which schedule a given structure is on.

The joint use agreement allocates cost, not answerability

Most joint-use relationships in California are managed through the Northern California Joint Pole Association or the Southern California Joint Pole Committee, whose handbooks set procedures for planning, replacement, transfers, removal, rights of way and record correction. Those documents are private, they work, and their authority runs between the signatories.

The Commission drew that line in the proceeding arising from the October 21, 2007 Malibu Canyon Fire, Investigation 09-01-018, where three wooden poles carrying facilities of Southern California Edison, Verizon Wireless, Sprint and NextG Networks broke and the downed lines started a 4,521 acre fire.

In the settlement, NextG admitted that it placed attachments on Pole 252E based on its interpretation of SCJPC rules rather than GO 95 requirements, and acknowledged that those rules and agreements may not be used to avoid compliance with applicable laws and regulations. The wireless carriers, who made no admissions, accepted the same position and agreed to address safety concerns even when raised outside the handbook's 45 day window.

Malibu Canyon was a pole loading case rather than a vegetation case, and the principle it settled is indifferent to which rule is at issue. Rule 18-A(1) puts corrective action for a condition on a company's facilities with that company, and an agreement allocating the field work and the invoice sits underneath that.

California's pole attachment statute behaves the same way. Public Utilities Code section 767.5 defines surplus space, excess capacity, usable space and rearrangements, and gives the Commission authority to set rates, terms and conditions when a utility and a cable television corporation fail to agree. It runs to several hundred words on cost allocation, and it uses the words vegetation, tree and trimming zero times. The statute that divides the pole is silent on what grows next to it.

And Rule 91.1 keeps the whole arrangement consensual: "Nothing herein shall be construed as requiring utilities to use poles jointly, or as granting authority for the use of any poles without the owner's consent."

Rule 12.6 is not the attacher's shelter

One rule in GO 95 forgives a nonconformance somebody else caused, and its qualifying clause decides which somebody. Rule 12.6:

When a third party that is not subject to the requirements of this Order causes a condition on or near a utility facility that does not conform with this Order, the utility shall be allowed reasonable time to address the condition by pursuing appropriate corrective action and/or notification procedures. While addressing this condition, the utility is in conformance with the Order.

The qualifying clause is "not subject to the requirements of this Order." A property owner who plants under a span, a sign contractor, a grower who stacks bins against a pole: those are third parties in the Rule 12.6 sense. A communications attacher sits inside the Order, because Rule 12 puts all overhead electrical supply and communication facilities within Commission jurisdiction inside it.

So where one occupant's work creates a nonconformance for another occupant, the governing provision is Rule 18-A(2), and the difference is real. Rule 12.6 grants the affected utility reasonable time and deems it in conformance while it works. Rule 18-A(2) grants the affected company one prescribed act, a single documented notice inside 180 days or 10 business days for a Safety Hazard, and then puts correction back on the company whose facility it is. One is an extension of time. The other is a handoff.

The branch at location 45, cut free of its trunk and left lying across the communications lines, is exactly this fact pattern. Somebody trimmed and left the material in the span. The condition sits on Comcast's facility, so it is Comcast's to correct and Comcast's to notify about, and the trimmer's identity changes the invoice rather than the obligation.

What the record has to name

A joint-use vegetation file answers to the same rules as any other, plus one axis nobody else has to carry. It should be able to produce, for any span:

The pole, and its occupants. The pole identifier and coordinate. Who owns the pole, and who else owns it. Every authorized attacher on it, which Rule 18's note requires the pole owner to be able to determine on demand. Whether each communications attachment carries a Rule 91.5 ownership marker, and where it lacks one, which of the three marking triggers remains unmet.

The facility the finding is against. The conductor, cable, messenger, guy or service drop the condition sits on, and who owns it. A finding written against a pole has nowhere to close, because every duty in this stack attaches to a facility.

The column the condition was priced in. Electric or Communications, by Appendix I, with the resulting priority level and the correction date that level produces under Rule 18-B(1). A condition reachable from both columns is classified in both, and the file should say so rather than picking one.

The notice, both ends of it. Who found it, on what date, under which subdivision of Rule 18-A. Who it went to, and whether that party was the facility owner or the pole owner acting as relay. The date sent, measured in business days from discovery. Where the pole owner was the relay, the date it forwarded. The 10 year retention obligation falls on both ends, which makes the send date the sender's own evidence.

The statutory overlay, and who it lands on. Whether the span is in an SRA, and therefore whether PRC 4292 and 4293 are live. Whose facility triggered subject pole status. What sits inside the ten foot firebreak that belongs to someone other than the party clearing it.

The inspection schedule the structure is actually on. GO 165 for supply, Rule 80.1 for communications. For a Tier 3 communications-only wood pole, add two more fields: the span count to the nearest joint-use supply pole, and the county. Those two decide whether Rule 80.1-B has pulled the pole onto GO 165's intrusive cycle.

One entry closes all of it, and it is the easiest to leave out: the date a finding on another company's facility was confirmed corrected. Rule 18-A(5) puts that documentation with the receiving party, which means the notifying company's file ends at "sent." A program that wants to know whether the tree on its pole came out has to ask for that separately, and has to ask before the span turns up on somebody's map with a fire behind it.

Further reading

• GO 95 Rule 35: what the vegetation clearance rule actually requires: The rule both companies on the pole are inside, read start to finish.

• Patrol and detailed inspection: two words, two orders, four clocks: The inspection intervals that run separately for the conductor and the cable below it.

• Who enforces what: CPUC, CAL FIRE, NERC and the utility: Which body issues what instrument against which company on a shared pole.

Frequently asked questions

On a joint-use pole, who has to trim the tree?

Both companies have a duty and the duties are different. GO 95 Rule 35 states that its requirements apply to all overhead electrical supply and communication facilities covered by the General Order. The Table 1, Case 13 and 14 clearances are written for bare line conductors, so the numeric clearance belongs to the electric utility. Rule 35's third paragraph puts the strain and abrasion duty on whichever company owns a circuit energized at 750 volts or less, which on most joint-use poles includes the communications attacher. Neither company's compliance answers for the other's.

Does a cable or telephone company owe anything under PRC 4292 or PRC 4293?

Not for its own communications plant. PRC 4292 says outright that it does not apply to any line used exclusively as a telephone, telegraph, messenger call, fire or alarm line, or other line classed as a communication circuit by the CPUC. PRC 4293 carries no such sentence, and it does not need one: it binds any person that owns, controls, operates, or maintains an electrical transmission or distribution line, and its clearance bands start at 2,400 volts. On a shared pole in a State Responsibility Area, the firebreak and the radial clearance are the electric utility's obligation alone.

Our joint use agreement says the electric utility performs all vegetation work. Are we covered?

For cost and scheduling, yes. For compliance, no. In the settlements arising from the 2007 Malibu Canyon Fire in CPUC Investigation 09-01-018, NextG Networks acknowledged that Southern California Joint Pole Committee rules and agreements may not be used to avoid compliance with applicable laws and regulations. A contract moves who performs the work and who pays for it. It leaves each company answering to the Commission for the condition of its own facilities under GO 95 Rule 18-A(1).

What do I do when I find vegetation on a facility that is not mine?

Notify the owner. GO 95 Rule 18-A(3) requires a company that discovers a Safety Hazard on or near another company's facility during inspection of its own to notify that company no later than 10 business days after discovery. If the owner cannot be determined, Rule 18-A(4) sends the notice to the pole owner within the same 10 business days, and the pole owner then has normally no more than five business days to pass it on. Rule 18-A(5) requires both the sender and the recipient to keep the notice for at least 10 years.

Does GO 165 apply to a communications attacher on a jointly used pole?

No. GO 165 states that it does not apply to facilities of communication infrastructure providers. GO 95 Rule 31.2 routes communication lines to Rule 80.1 instead. One proximity rule crosses the line anyway: Rule 80.1-B puts a Tier 3 wood pole carrying only communications on GO 165's intrusive inspection schedule when it is interset between or within three spans of a joint-use pole supporting supply lines in Southern California, or within one span of one in Northern California.