FAC-003-3: Transmission Vegetation Management

Purpose
To maintain a reliable electric transmission system by using a defense-in-depth strategy to manage vegetation located on transmission rights of way (ROW) and minimize encroachments from vegetation located adjacent to the ROW, thus preventing the risk of those vegetation-related outages that could lead to Cascading.

Applicability
4.1. Functional Entities:

4.1.1. Applicable Transmission Owners

4.1.1.1 Transmission Owners that own Transmission Facilities defined in 4.2.

4.1.2  Applicable Generator Owners

4.1.2.1  Generator Owners that own generation Facilities defined in 4.3

4.2. Transmission Facilities: Defined below (referred to as “applicable lines”), including but not limited to those that cross lands owned by federal1, state, provincial, public, private, or tribal entities:

4.2. 1 Each overhead transmission line operated  at 200kV or higher.

4.2.2 Each overhead transmission line operated below 200kV identified as an element  of an IROL under NERC Standard FAC-014 by the Planning Coordinator.

4.2.3 Each overhead transmission line operated below 200 kV identified as an  element of a Major WECC Transfer Path in the Bulk Electric System by WECC.

4.2.4 Each overhead transmission line identified above (4.2.1 through 4.2.3) located  outside the fenced area of the switchyard, station or substation and any portion of the span of the transmission line that is crossing the substation fence.

4.3. Generation Facilities: Defined below (referred to as “applicable lines”), including but not limited to those that cross lands owned by federal 2 , state, provincial, public, private, or tribal entities:

4.3.1  Overhead transmission lines that (1) extend greater than one mile or 1.609 kilometers beyond the fenced area of the generating station switchyard to the point of  interconnection with a Transmission Owner’s Facility or (2) do not have a clear line of sight 3  from the generating station switchyard fence to the point of interconnection with a Transmission Owner’s Facility and are:

4.3.1.1   Operated at 200kV or higher; or

4.3.1.2   Operated below 200kV identified as an element of an IROL under NERC  Standard FAC-014 by the Planning Coordinator; or

4.3.1.3   Operated below 200 kV identified as an element of a Major WECC Transfer  Path in the Bulk Electric System by WECC.

Effective Date
[Please see the full standard for effective date information -LW]

Requirements and Measures   
R1.   Each applicable Transmission Owner and applicable Generator Owner shall manage vegetation to prevent encroachments into the MVCD of its applicable line(s) which are either an element of an IROL, or an element of a Major WECC Transfer Path; operating within their Rating and all Rated Electrical Operating Conditions of the types shown below 4  [Violation Risk Factor: High] [Time Horizon: Real-time]:

  1. An encroachment into the MVCD as shown in FAC-003-Table 2, observed in  Real-time, absent a Sustained Outage, 5
  2. An encroachment due to a fall-in from inside the ROW that caused a vegetation- related Sustained Outage, 6
  3. An encroachment due to the blowing together of applicable lines and vegetation  located inside the ROW that caused a vegetation-related Sustained Outage 7,
  4. An encroachment due to vegetation growth into the MVCD that caused a  vegetation-related Sustained Outage 8.

M1.  Each applicable Transmission Owner and applicable Generator Owner has evidence that it managed vegetation to prevent encroachment into the MVCD as described in R1. Examples of acceptable forms of evidence may include dated attestations, dated reports containing no Sustained Outages associated with encroachment types 2 through 4 above, or records confirming no Real-time observations of any MVCD encroachments. (R1)

R2.   Each applicable Transmission Owner and applicable Generator Owner shall manage  vegetation to prevent encroachments into the MVCD of its applicable line(s) which are not either an element of an IROL, or an element of a Major WECC Transfer Path; operating within its Rating and all Rated Electrical Operating Conditions of the types shown below 9  [Violation Risk Factor: High] [Time Horizon: Real-time]:

  1.   An encroachment into the MVCD, observed in Real-time, absent a Sustained  Outage, 10
  2. An encroachment due to a fall-in from inside the ROW that caused a vegetation related Sustained Outage, 11
  3. An encroachment due to blowing together of applicable lines and vegetation located  inside the ROW that caused a vegetation-related Sustained Outage 12 ,
  4. An encroachment due to vegetation growth into the line MVCD that caused a  vegetation-related Sustained Outage 13

M2.  Each applicable Transmission Owner and applicable Generator Owner has evidence  that it managed vegetation to prevent encroachment into the MVCD as described in R2.  Examples of acceptable forms of evidence may include dated attestations, dated reports containing no Sustained Outages associated with encroachment types 2 through 4 above, or records confirming no Real-time observations of any MVCD encroachments. (R2)

R3.   Each applicable Transmission Owner and applicable Generator  Owner shall have documented maintenance strategies or procedures or processes or specifications it uses to prevent the encroachment of vegetation into the MVCD of its applicable lines that accounts for the following:

3.1  Movement of applicable line conductors under their Rating and  all Rated Electrical Operating Conditions;

3.2  Inter-relationships between vegetation growth rates, vegetation  control methods, and inspection frequency.  [Violation Risk Factor: Lower] [Time Horizon: Long Term Planning]

M3.  The maintenance strategies or procedures or processes or specifications provided  demonstrate that the applicable Transmission Owner and applicable Generator Owner can prevent encroachment into the MVCD considering the factors identified in the requirement. (R3)

R4.   Each applicable Transmission Owner and applicable Generator Owner, without any  intentional time delay, shall notify the control center holding switching authority for the associated applicable line when the applicable Transmission Owner and applicable Generator Owner has confirmed the existence of a vegetation condition that is likely to cause a Fault at any moment [Violation Risk Factor: Medium] [Time Horizon: Realtime].

M4.  Each applicable Transmission Owner and applicable Generator Owner that has a  confirmed vegetation condition likely to cause a Fault at any moment will have evidence that it notified the control center holding switching authority for the associated transmission line without any intentional time delay.  Examples of evidence may include control center logs, voice recordings, switching orders, clearance orders and subsequent work orders. (R4)

R5.   When a applicable Transmission Owner and applicable Generator Owner is constrained  from performing vegetation work on an applicable line operating within its Rating and all Rated Electrical Operating Conditions, and the constraint may lead to a vegetation encroachment into the MVCD prior to the implementation of the next annual work plan, then the applicable Transmission Owner or applicable Generator Owner shall take corrective action to ensure continued vegetation management to prevent encroachments [Violation Risk Factor: Medium] [Time Horizon: Operations Planning].

M5.  Each applicable Transmission Owner and applicable Generator Owner has evidence of  the corrective action taken for each constraint where an applicable transmission line was put at potential risk.  Examples of acceptable forms of evidence may include initially-planned work orders, documentation of constraints from landowners, court orders, inspection records of increased monitoring, documentation of the de-rating of lines, revised work orders, invoices, or evidence that the line was de-energized. (R5)

R6.   Each applicable Transmission Owner and applicable Generator Owner shall perform a  Vegetation Inspection of 100% of its applicable transmission lines (measured in units of choice – circuit, pole line, line miles or kilometers, etc.) at least once per calendar year and with no more than 18 calendar months between inspections on the same ROW 14  [Violation Risk Factor: Medium] [Time Horizon: Operations Planning].

M6.  Each applicable Transmission Owner and applicable Generator Owner has evidence that it conducted Vegetation Inspections of the transmission line ROW for all applicable lines at least once per calendar year but with no more than 18 calendar months between inspections on the same ROW. Examples of acceptable forms of evidence may include completed and dated work orders, dated invoices, or dated inspection records. (R6)

R7.   Each applicable Transmission Owner and applicable Generator Owner shall complete  100% of its annual vegetation work plan of applicable lines to ensure no vegetation encroachments occur within the MVCD.  Modifications to the work plan in response to changing conditions or to findings from vegetation inspections may be made (provided they do not allow encroachment of vegetation into the MVCD) and must be documented.  The percent completed calculation is based on the number of units actually completed divided by the number of units in the final amended plan (measured in units of choice – circuit, pole line, line miles or kilometers, etc.) Examples of reasons for modification to annual plan may include [Violation Risk Factor: Medium] [Time Horizon: Operations Planning]:

  • Change in expected growth rate/ environmental factors
  • Circumstances that are beyond the control of an applicable Transmission Owner or  applicable Generator Owner 15
  • Rescheduling work between growing seasons
  • Crew or contractor availability/ Mutual assistance agreements
  • Identified unanticipated high priority work
  • Weather conditions/Accessibility
  • Permitting delays
  • Land ownership changes/Change in land use by the landowner
  • Emerging technologies

M7.  Each applicable Transmission Owner and applicable Generator Owner has evidence  that it completed its annual vegetation work plan for its applicable lines.  Examples of acceptable forms of evidence may include a copy of the completed annual work plan (as finally modified), dated work orders, dated invoices, or dated inspection records. (R7)

  1. EPAct 2005 section 1211c: “Access approvals by Federal agencies.”.
  2.  Id.
  3. “Clear line of sight” means the distance that can be seen by the average person without special instrumentation (e.g., binoculars, telescope, spyglasses, etc.) on a clear day.
  4. This requirement does not apply to circumstances that are beyond the control of an applicable Transmission Owner or applicable Generator Owner subject to this reliability standard, including natural disasters such as earthquakes, fires, tornados, hurricanes, landslides, wind shear, fresh gale, major storms as defined either by the applicable Transmission Owner or applicable Generator Owner or an applicable regulatory body, ice storms, and floods; human or animal activity such as logging, animal severing tree, vehicle contact with tree, or installation, removal, or digging of vegetation.  Nothing in this footnote should be construed to limit the Transmission Owner’s or applicable Generator Owner’s right to exercise its full legal rights on the ROW.
  5. 5  If a later confirmation of a Fault by the applicable Transmission Owner or applicable Generator Owner shows that a vegetation encroachment within the MVCD has occurred from vegetation within the ROW, this shall be considered the equivalent of a Real-time observation.
  6. Multiple Sustained Outages on an individual line, if caused by the same vegetation, will be reported as one outage regardless of the actual number of outages within a 24-hour period.
  7. Id
  8. Id.
  9. See footnote 4.
  10. See footnote 5.
  11. See footnote 6.
  12. Id.
  13. Id.
  14.   When the applicable Transmission Owner or applicable Generator Owner is prevented from performing a Vegetation Inspection within the timeframe in R6 due to a natural disaster, the TO or GO is granted a time extension that is equivalent to the duration of the time the TO or GO was prevented from performing the Vegetation inspection.
  15.  Circumstances that are beyond the control of an applicable Transmission Owner or applicable Generator Owner include but are not limited to natural disasters such as earthquakes, fires, tornadoes, hurricanes, landslides, ice storms, floods, or major storms as defined either by the TO or GO or an applicable regulatory body.

Top