The State of the Utility Vegetation Management (UVM) Industry

The State of the Utility Vegetation Management (UVM) Industry


Are we ready to comply with new regulatory requirements and expectations?

By Stephen Cieslewicz

On August 14th 2003, the United States and Canada experienced the single largest tree-related blackout in our collective history. Front page media coverage, billions of dollars in lost productivity, accidents, fatalities, and fifty-plus million people left in the dark for extended periods of time. In addition to the subsequent utility industry self scrutiny of this event, this incident captured the focused attention of almost every appointed or elected official who had any type of direct and/or indirect authority over utility company maintenance and operations. Simply put, everyone, from the President of the United States and the Prime Minister of Canada, down through all Federal and State/Provincial energy regulatory bodies, wanted to take tangible steps to prevent this from happening again in the future.

One of several locations where on August 14th 2003 a tree related outages contributed to the Northeast Blackout.

While two years may seem like a lot of time since the event, the Utility Vegetation Management (UVM) industry has only recently begun to see the full impact of the post-blackout efforts and inquiries. While it is true that many initiatives occurred shortly after the blackout (new utility reporting requirements to oversight agencies, and more focused attention on UVM programs and in preventing transmission tree related outages) it has only been recently that the industry has begun to see new mandatory UVM requirements being promulgated by various regulatory bodies.

Unlike other utility company functions and activities, the UVM industry has not, for the most part, had to deal with a large amount of regulatory requirements and oversight. Based on our past assessments of applicable UVM laws and regulations, the majority of utilities have simply had to comply with the current NESC Rule 218 requirements. For those not familiar with Rule 218, it generally requires that “trees that interfere with ungrounded supply conductors should be trimmed or removed”. The Rule also makes brief references to consideration of sag and sway, addressing crossing lines, and a reference to construction alternatives. While a few individuals may argue otherwise, the Rule is generally interpreted to require utilities to perform a “reasonable” amount of UVM work. It does not specify cycles, clearances, program requirements, performance objectives, or any other type of requirement that would result in meeting specific UVM objectives. In short, it is highly subjective and limited both in its enforceability and efficacy.

While we would argue that utilities have historically done a much better job than the NESC Rule 218 actually required, we fully expect that the bar is about to be raised much higher. Utilities are in fact going to be required to adhere to new and stricter UVM requirements than they have seen in the past, along with seeing a greater level of regulatory scrutiny. And to be certain, these new requirements and oversight will call for utilities to devote more attention and resources to the important task of keeping vegetation from conflicting with energized lines.

What can we expect?

The latest and likely most influential new UVM requirements are those presently being considered for adoption by the North American Electric Reliability Council (NERC). These new requirements will impact, to varying degrees, each and every transmission UVM operation working under the aegis of NERC. In brief, the new NERC UVM requirements include:

1. New UVM reporting requirements for all tree/vegetation related outages

2. New standard program requirements for all Transmission UVM programs

a. Development of formal annual UVM plans

b. Program and employee qualifications and requirements

c. Self certification and audits of compliance

3. New mandatory clearance requirements to be achieved and maintained between trees/vegetation and energized transmission lines

a. Clearances to be achieved at time of work will be determined by the utility

b. Clearances to be maintained are mandatory

New rules and regulations will soon impact transmission UVM programs

Based on our past UVM benchmarking with over 55 utility companies in North America, the number 1 and 2 requirements should not be overly burdensome for most utilities. Yes, some utilities will need to develop more structured programs but most utilities should be able to comply given a reasonable effort and the support of utility management. The truly dramatic changes to UVM programs will result from efforts to comply with the mandatory clearance requirements found in requirement 3. A mandatory clearance requirement is exactly what the name suggests. No vegetation can grow within specific distances adjacent to energized lines. In the case of this new NERC requirement, the absolute minimum clearances (see b above) are based on flash-over distances found in the Institute of Electrical and Electronics Engineers (IEEE) Standard 516-2003 (Guide for Maintenance Methods on Energized Power Lines) and as specified in its Section, Minimum Air Insulation Distances Without Tools in the Air Gap. The thought process behind these clearances is quite simple. If utilities keep all vegetation out of these required “minimum” clearance zones, there should be no growth
related outages on any transmission circuit.

While the concept sounds relatively straight-forward, (keep the trees from growing into close proximity to all the lines) not very many utilities have actually had any experience in achieving these types of clearances for any period of time. For the less than 10% of utilities that have complied with mandatory clearances in the past, they will all tell you it is not an easy undertaking. Mandatory clearance requirements require new and improved scheduling requirements, significantly increased UVM budgets, shortened inspection cycles, and a great deal more effort and resources devoted to the task of keeping vegetation away from the lines.

New NERC standards include mandatory clearances that must be maintained between transmission lines and all vegetation

To understand the impacts that a new UVM requirement can have, one need only look to what happened to California utilities several years ago when the Public Utility Commission adopted mandatory clearances for transmission and distribution high-voltage lines. Here are a few highlights:

• California utilities have had to triple their UVM budgets to comply with mandatory clearance requirements – this also reflects current funding levels (it was not a one time expense)

• California utilities generally utilize an annual UVM cycle on transmission and distribution lines as opposed to the industry average range of 3.5 to 4.5 years

• California utilities necessarily spend significantly more time and money on pre-inspection, post-auditing, and quality assurance programs than other utilities.

The point in the preceding is to illustrate that complying with a new mandatory clearance requirements is not as intuitive or as simple as one may think. It is also much costlier than you might ever imagine. Here is an example to think about. We know, based on our benchmarking, that
utilities across North America (excluding California) have approximately 30% of their trees in contact with high-voltage distribution lines at any given moment in time. Given that statistic, how would you answer the following 2 questions?

• What percentage would you have to increase your budget in order to get 100% of your trees in compliance with a mandatory clearance requirement?

• How much of an increase would you need long-term to maintain those clearances?

As best we can tell, the actual answers are identical to what California utilities experienced. You would likely need to triple your budgets for the long-term. Their experience has shown that in order to get “the last 30%” you need to exponentially increase your patrols, your travel time, and alter your pruning and removal criteria and work to achieve a level three times greater than you are currently doing. Don’t believe me? Call someone at SCE, PG&E or SDG&E.

Fortunately, it is unlikely you will have to triple your entire budget (at least in the near future). The new NERC requirements will only require that you maintain clearances between vegetation and conductors energized at transmission voltages. And, as most utilities recognize, the majority of transmission corridors are already in much better shape (regarding clearances) than are the
distribution circuits. However, these new requirements will have an impact, in one way or another, on every utility that maintains vegetation adjacent to transmission facilities.

Distribution UVM – This is not just a Transmission Issue
A While it is correct to suggest that the Northeast Blackout was principally related to transmission issues, don’t assume that Distribution UVM operations will be exempt from resulting new requirements and/or increased regulatory scrutiny. Quite the opposite seems to be happening.

As we all well know, tree and power line conflicts are not limited to transmission lines. In fact, trees have always represented the single greatest threat to electric service reliability on the majority of distribution systems in North America. This fact, coupled with the notoriety of the northeast blackout has led several states to also take a hard look at distribution UVM operations within their own jurisdiction. For example, shortly after the northeast blackout the Governor of Illinois commissioned a study to look at all aspects of the outage, and how they specifically related to the State. One of the many resulting recommendations was the need to strengthen current UVM requirements on the distribution side of the house. And to be sure, Illinois was not alone. Several other states, principally along the eastern seaboard, also began to take a look at distribution UVM programs. In our routine tracking of UVM-related legal and regulatory initiatives, we have noticed a recent increase in attention being paid to tree and power line issues.

The likelihood of new distribution UVM
regulations and requirements is further evidenced by the actions of groups such as the National Association of Regulatory Commissioners (NARUC). Anyone who has been monitoring the post-blackout investigations and initiatives knows full well that NARUC has been actively involved in almost every UVM related issue. This included helping develop and author FERC’s UVM report to Congress on September 7th, 2004, and in adopting their own UVM-specific resolution two months afterwards.
It appears that in the process of investigating the causes and issues surrounding the Northeast Blackout, regulators have seen a connection between transmission and distribution systems. In other words, if they can come up with requirements that will reduce the likelihood of transmission outages, why can’t they do the same for the distribution side of the house?

Distribution lines may soon be subject to new UVM regulations and requirements

We are convinced that it is not an issue of whether or not we will see changes to current
distribution UVM requirements; it is a question of what will they look like and when will they be promulgated.

So What Should We Do About New UVM requirements?
For starters, utilities should become very familiar with the new UVM requirements that are being promulgated by NERC. This will be the dominant requirement for all transmission UVM programs moving forward. You can download a copy here:

Once utilities are familiar with the new requirements they should be evaluating their UVM programs to identify exactly what needs to be adjusted in order to comply with any new requirements. For starters, this evaluation should include:

1. Quantifying your workload: Do you know with certainty, exactly how much work you need to do in order to comply with any new requirements?

2. Evaluate your current resource
assumptions: Will you need to add resources in order to comply with new requirements?

3. Evaluate current scheduling assumptions: Will your current method of scheduling required work satisfy new requirements?

4. Evaluate compliance and quality assurance processes: How will you know if you are in compliance?

You may also consider talking to others in the industry to see how they plan on complying with the new requirements. A few phone calls may save you a great deal of frustration down the road.

In addition to preparing for the latest national transmission requirements, utilities should be paying equal attention to the possibility that new and unique regulations for distribution UVM operations will appear on a state by state basis. If and when they are identified, utilities should become actively involved in the entire process. This would include evaluating the actual need for new requirements and, if necessary, helping to craft workable provisions for the final regulations. Far too often utilities have simply waited until the new rules have been promulgated, rather than providing effective input during the entire process.

In summation, it is very probable that the UVM industry is on the verge of seeing a great deal more scrutiny and regulation than they have become accustomed to in the past. The Northeast Blackout has made this inevitable for transmission operations and also very likely on the distribution side of the business. The level of impact any new requirements will have on a UVM program is relative to each specific utility. To some utilities these new requirements will not create any dramatic changes, whereas some utilities will require significant changes and considerable investments of new resources.

It is probably best to close with a simple statement (and awful epigram) that I recently overheard being made by a state regulator. “The current utility tree clearing requirements are simply not cutting it.”

Stephen R. Cieslewicz is currently President of CN Utility Consulting and has over 20 years of
experience in the Utility Vegetation Management (UVM) industry. He was one of the Principal UVM investigators for the Federal Energy Regulatory Commission (in support of the federal investigation of the August 14th, 2003 Northeast Blackout) and has co-authored several of the resulting official reports. His firm works with utility companies, regulators, and industry service providers on all issues/projects related to UVM.

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