An independent review of field and laboratory testing concludes that wooden utility poles protected against ground-line decay could achieve an additional 20 years of service life.

The review, commissioned by Polesaver and conducted by American wood preservation expert Craig R. McIntyre of McIntyre Associates Inc., examines more than 30 years of field data, laboratory testing and utility experience involving ground-line protection barriers.

The assessment focuses on factors that influence the long-term performance of wooden poles, including moisture ingress, biological decay and the retention of wood strength. The ground-line section is particularly vulnerable to moisture and environmental conditions that can promote fungal decay and structural deterioration.

The evidence reviewed includes several independent testing programs:

• Eight years of field exposure testing in Uganda.
• Ten years of independent field testing on wooden poles in England.
• Twenty-five years of independent field testing on wooden stakes.
• Four years of utility-commissioned soil-bed testing examining the retention of wood strength.
• Moisture-ingress testing evaluating the performance of complete and partial barriers.

Together, the studies provide a basis for evaluating how ground-line protection systems perform under different environmental conditions and over extended exposure periods.

The review examines how barriers designed to limit moisture penetration at the ground line may help reduce the biological decay that contributes to the deterioration of wooden poles.

For electric utilities, pole service life is an important consideration in distribution asset management, maintenance planning and replacement schedules. Premature pole deterioration can increase the need for inspections, maintenance and replacement, making long-term structural performance an important factor in managing distribution infrastructure.

The review was authored by McIntyre, whose professional affiliations include organizations and standards bodies associated with wood preservation, forestry, materials testing and industry standards, including ASTM, AWPA, ANSI, AFPA, ICC and SWST.