When Hurricane Helene brought devastating flooding to eastern Tennessee, utilities throughout the region faced extensive damage. Floodwaters along the Nolichucky River washed away utility infrastructure, leaving electric cooperatives and municipal utilities with the challenge of restoring service while preparing their systems to better withstand future storms. For both Erwin Utilities and Mountain Electric Cooperative, the recovery effort highlighted the challenges of rebuilding and maintaining infrastructure in areas vulnerable to severe weather.

Rebuilding After the Flood at Erwin Utilities

Erwin Utilities provides electric and fiber optic services throughout most of Unicoi County and portions of Washington and Carter counties, as well as water and wastewater services in Unicoi County. When floodwaters destroyed sections of power lines supported by traditional wood poles, the utility viewed the recovery as an opportunity not only to restore service but also to improve the long-term resilience of its electric system.

As part of its river corridor rebuild, Erwin Utilities selected ductile iron poles from McWane Poles.. Ductile iron was selected as an alternative to wood, while availability provided a shorter lead time than comparable steel poles, according to the utility.. During a critical recovery period, that availability helped keep the rebuilding work moving.

To further strengthen the installation, crews set many of the poles five feet deeper than standard practice and backfilled the bottom five feet of each hole with concrete to provide additional resistance against future flood forces.

Installation Considerations

Beyond their the material selection, crews also considered installation requirements during the rebuild. Crews noted they were easier to drill than comparable steel poles, improving installation efficiency while providing flexibility throughout the reconstruction process.

Throughout the project, the McWane Poles team provided technical guidance, installation demonstrations and training on drilling techniques.

Mountain Electric Cooperative’s Experience

While Erwin Utilities selected ductile iron poles as part of its rebuilding efforts, Mountain Electric Cooperative (MEC) had already been incorporating ductile iron poles into its distribution system for years.

Headquartered in Mountain City, Tennessee, MEC is a member-owned electric cooperative serving more than 36,000 members across a 700-square-mile service territory in northeast Tennessee and northwest North Carolina.

The cooperative originally sought a long-term solution for critical distribution poles located in remote areas where replacement was labor intensive and costly. Traditional wood poles in these locations were increasingly vulnerable to vehicle impacts, severe weather, and natural deterioration, creating recurring maintenance challenges.

By replacing those critical structures with ductile iron poles, MEC sought to reduce the need for future replacements in these difficult-to-access locations. For a cooperative serving many rural communities located miles from the nearest town, the ability to reduce maintenance and replacement work can be an important consideration when managing infrastructure across a large rural service territory.

Like the Erwin Utilities crews, the MEC crews also reported that installation was relatively straightforward.. Unlike some alternative materials, ductile iron poles can be drilled and modified using familiar tools and techniques without requiring specialized equipment. McWane representatives provided hands-on training during the initial installations and continue to offer support for new lineworkers joining the cooperative.

Hurricane Helene Provides a Test

When Hurricane Helene struck in September 2024, Mountain Electric Cooperative experienced catastrophic damage, with more than 1,400 poles broken or displaced across its service territory.

Despite the widespread destruction, the cooperative reported no failures among its installed ductile iron poles.

In one particularly remote seven-mile section of distribution line through a national forest, nearly the entire circuit was brought to the ground after a large tree fell into the line. Of all the ductile iron poles along that route, only a single pole was bent, and even then, it remained standing and structurally serviceable. According to MEC, that pole continues to support the line..

Elsewhere, the ductile iron poles remained standing in raging floodwaters that carried away neighboring wood poles, according to the cooperative.

For MEC the experience provided an opportunity to assess how the poles performed during a major storm event.

Investing in Resilience

Although Erwin Utilities and Mountain Electric Cooperative approached the ductile iron pole installation from different starting points – one rebuilding after disaster and the other making strategic long-term infrastructure investments – both utilities have incorporated the material into their distribution systems..

Ductile iron poles are one option utilities can consider when evaluating pole materials for distribution infrastructure.. Whether rebuilding after a major storm or replacing aging infrastructure, utilities must weigh factors including installation, maintenance, replacement and performance under severe weather conditions..