SCE 2018 GRC Deep Dive on SCE T estimony on Poles November 2, - PowerPoint PPT Presentation

SCE 2018 GRC – Deep Dive on SCE T estimony on Poles November 2, 2016 1

Summary  Pole inspection, assessment, maintenance, and replacement continue to be a major focus for SCE given: Their impact on public and worker safety  Their essential role in service reliability for customers  The amount of resources needed to maintain the asset base while meeting compliance  The operational complexities associated with  Assets distributed across the territory with regional environmental impacts  Joint ownership   SCE evaluates its existing programs regularly to improve efficiency and effectiveness including, but not limited to: Inspection criteria and schedule  Replacement standards  Technology improvements  Risk analysis using probabilistic methods   SCE has actively pursued the directives from the 2015 GRC in conjunction with the self-identified improvements. 2

Agenda • Review of Deteriorated Pole Program • Review of Pole Loading Program (PLP) • Pole Replacement Unit Cost • Compliance with Commission Requirements • Questions 3

Regulatory Background on Poles GO 165 Inspection Cycles for Distribution Facilities • – Beginning in 1998, required all poles over 15 years old be intrusively inspected within 10 years, and then at least once every 20 years – SCE completed initial inspections of all poles in 2007 – Poles requiring replacement are replaced through SCE’s Deteriorated Pole Replacement Program GO 95 Design, Construction and Maintenance of Overhead Lines • – Sets pole design safety factor of 4.0 for new grade A wood poles – Sets pole design safety factor minimum of 2.67 at 6 or 8 lbs for in-service grade A wood poles – Requires a ‘pole loading’ calculation to evaluate safety factor – Requires retention of pole loading records for life of the pole (added to G.O. 95 by D.12-01-032) – GO 95 safety factor compliance drives SCE’s Pole Loading Program 4

Deteriorated Pole Replacement Program 5

Intrusive Pole Inspection (IPI) Process Process Overview: – Drill into pole’s interior in order to identify and measure extent of internal decay – Involves digging, boring, and sounding depending on type of pole and its setting – Visually inspect poles as appropriate for signs of external damage (e.g. vehicle, woodpeckers, etc.) Younger than 10 years old • Inspected intrusively under • current Cycle (2007-current) 6

Intrusive Pole Inspection (IPI) Cycle • Implemented a 10-year, grid-based system of inspection in 2009 – What: Poles were segmented into geographic grids; grids assigned over multi-year inspection cycle • 10-year inspection cycle • – Why: Inspection interval consistent with industry best practices • Consistent with expected efficacy of wood treatment applied to poles during inspections • – Current status: Transition as poles previously not inspected became due, e.g. annual intrusive inspections were combination of grid • inspections and compliance poles Transition will be complete in early 2018; after that, virtually all poles will be inspected on a grid basis • Has lowered unit cost per pole of inspections • • Overall lower failure rates from Intrusive Inspections with initial GO 165 cycle completed (Table III – 10) Aggregate Failure Rate Inspection Year (Distribution and Transmission) 2013 ‐ 2015 8% 2008 ‐ 2012 7% 2001 ‐ 2007 17% 7

Remediation Timeframes Remediation Timeframes – Deteriorated Pole Program SCE ‐ Driven Remediation Determinants of Priority Timeframe* 72 hrs / 45 days 1 Year Remaining Section Modulus (RSM), other visible damage, location, size, etc. 2 Years 3 Years *Not to exceed time frames, poles may be replaced earlier due to operational circumstances, environmental clearances, or opportunities to reduce customer impact. 8

Intrusive Pole Inspection (IPI) Changes Program Changes: RSM failure & RSM failure & RSM pass with become Utility become restoration no action replacement candidate candidate – Adjusted replacement criteria for when void is found (effective April SCE 100% N/A N/A 2016) 1 70% 69.90% 40% Benchmarking identified areas for • better alignment with peer companies 2 100% N/A N/A Team utilized risk-based model to 3 >67% <67% <67% • assess impact of changes and identify 4 66% 66% 66% new criterion 5 100% 99% 99% 6 80% 67 ‐ 80% 67% – New specification will reduce the number of poles requiring 7 71% 41 ‐ 70% 70% replacement 8 67% 66% 50% Poles with higher RSM values will not 9 66% 66% 66% • require replacement 10 >67% <67% <67% The use of steel stubbing to restore • 11 >67% <33% <33% versus replace poles 12 67% 14 ‐ 67% 0 ‐ 13% 13 >88% 34 ‐ 87% <33% 14 >81% 34 ‐ 80% <33% 9

Intrusive Pole Inspection (IPI) Changes Cont. Program Changes: – 2018 GRC forecast reflects the changes Anticipated Failure Rates Dates Remediation Transmission Distribution 2015 Reject Rate Pole Replacement 12.50% 7.63% (Before SPEC Change) Restoration 2% 2% Estimated 2016 Reject Rate (After SPEC Change) Pole Replacement 4.23% 3.75% 10

Pole Volume Forecast Compared to Recorded Total recorded pole replacements were consistent with the forecast, but there were variances at the program level (Table I-1) Total, 2013- 15 2013 2014 2015 2015 GRC Forecast Replacements PLP 3,000 25,000 28,000 Det Pole 7,500 7,600 8,102 23,202 Total, All Programs 7,500 10,600 33,102 51,202 Recorded Replacements PLP - 299 10,690 10,989 Det Pole 12,251 14,065 23,198 49,514 Total, All Programs 12,251 14,364 33,888 60,503 Forecast vs. Recorded Variance PLP - (2,701) (14,310) (17,011) Det Pole 4,751 6,465 15,096 26,312 Total Variance 4,751 3,764 786 9,301 PLP replacements lower than forecast due to fewer assessments than forecast and fewer one-year due poles • Poles from non-programmatic pole replacement and PLC-driven replacements higher than forecast • Clarification of visual reject specifications resulted in increased rejects under the Det Pole Program • Change in one-year due pole replacement criteria and shift in scope from 2016 into 2015 • 11

Pole Loading Program (PLP) 12

Pole Loading Program (PLP) Process Process Overview: – Experienced assessor accesses pole to gather information for pole loading calculation: Pole class (size), length, wood species, and groundline circumference, • Height, size, number, type and span length of attached conductors, as well as the size and weight • of attached equipment, Height, number, and lead of guys supporting the pole and its attachments • – Desktop analysis completed to integrate data from the field assessment, design standards, and other data associated with the pole – Measurements are entered into the pole loading software (SPIDACalc), appropriate wind loading case is selected, and safety factors are calculated – Poles that are not compliant with G.O. 95 safety factors or SCE internal standards are identified and the appropriate remediation is designed and implemented. – Remediation requires replacement or repair of the pole, including removal and reinstallation of all attachments. – SCE began systematic assessment, evaluation, and remediation of poles in 2014 2015 GRC approved a 7-year assessment plan • Approximately 200,000 PLP assessments required to be completed each year • 13

Pole Replacement Process • Poles identified for repair or replacement, poles are Identified for Remediation grouped and work order number is assigned Released for Design • Poles assigned to design resource • Work orders in approval process, design completed, Design Approval Joint Pole Agreements initiated, environmental, rights checks/railroad request submitted • Work orders approved and pending release to Pole Program Clearance construction based on all constraints being cleared • Work scope is assigned to construction resources and Released to Construction in scheduling process for final execution • Pole is installed in field and considered “used and Installation useful” 14

Remediation Timeframes Remediation Timeframes – Pole Loading Program SCE ‐ Driven Remediation Determinants of Priority Timeframe* 72 hrs / 45 days 150 days Safety factor, location in high fire zones, presence of internal / external damage, etc. 1 year 59 months *Not to exceed time frames, poles may be replaced earlier due to operational circumstances, environmental clearances, or opportunities to reduce customer impact. 15

Pole Loading Program Changes Program Changes: – SCE implemented new wind ratings across the service territory based on REAX wind study and historical information Introduced a new 24 pound per square foot wind area and increased number of poles in • 12 psf and 18 psf areas New wind ratings implemented March, 2014 • – Enhancements to SpidaCalc Pole Loading Software The software enhancements allow wire tensions to change as the pole deflects under • various loads. (See workpaper pages 120-122) SCE initially estimated approximately 19% Failure Rate for Assessed Poles • Based on 5,000 pole sample filed with the Commission in July 2013 • Current forecast failure rate is 9% • – 2018 GRC forecast reflects the changes 16