A smiling worker in a red coverall and helmet sits on a walkway atop a series of large horizontal pipelines, surrounded by welding equipment and cables. The forested landscape stretches in the background, with scaffolding visible at the edge of the frame.

Penstock Inspection

Hydroelectric or hydroelectric energy has been a part of New Zealand’s energy system for over 100 years, providing more than half of the country’s electricity needs. Hydroelectric energy and our hydro stations are currently the primary renewable energy sources in New Zealand, and frequent inspection, repair, and ongoing maintenance are key to protecting our energy sources.

Penstocks are pipes or long channels that carry water from the hydroelectric reservoir to the turbines, making them critical infrastructure. Abseil Access has provided specialist services to maintain penstocks for major hydro facilities and clients across NZ, including Meridian Energy & Trust Power NZ, since 1996.

Penstock inspection up close.
Our penstock integrity inspection services include:
  • Confined Space Entry (CSE)
  • Industrial Rope Access
  • Concrete Condition Inspection
  • Coating & Corrosion Surveys
  • Cathodic Protection Surveys
  • Non-Destructive Testing (NDT)
  • Concrete & Coating Remediation
  • Anode Replacement
  • Spillway Inspection & Maintenance
  • Shutdown Service & Support

Penstock Specialist Access Services

Penstock access services.

Abseil Access offer comprehensive specialist access services to penstocks and hydro facilities, including industrial rope access and confined space entry (CSE). Since 1992, the Abseil Access team has provided specialist access solutions to the hydroelectric market, such as surveying, NDT and inspection, industrial maintenance, and current cathodic protection and coating repairs.

Penstock Integrity Inspection

Penstock inspection.

Deterioration of concrete or coating protection systems in penstocks can quickly become a real challenge for hydroelectric plant operators, costing significant amounts in remediation and repair if not identified and dealt with early. Abseil Access provides comprehensive inspection of concrete and steel penstocks, as well as detailed reports and recommendations to enable our clients to manage the integrity of their assets or structures proactively.

Our Group’s inspection pedigree, access services, and concrete or coating protection maintenance capabilities ensure the Abseil Access team can provide safe, high-quality, and cost-effective solutions for penstocks.

Penstock Remediation & Repair

A worker in bright orange overalls and a red helmet is welding inside a large, dimly lit pipe. Sparks fly as the welder concentrates on joining metal components, with green fluorescent markings visible on the pipe surface.

Corrosion, erosion, and degradation of steel and concrete penstocks can occur for various reasons, such as incorrect application, wear, surface damage from scouring, or lack of cathodic protection.

The Abseil Access team has provided a range of magnesium sacrificial anode installations, coating surveying and remediation, and concrete inspection, maintenance, and repair services to penstocks across New Zealand to ensure our client’s assets’ continued protection and operations.

Case Studies

Impressed Current Cathodic Protection.
Impressed Current Cathodic Protection
Manapouri Hydroelectric Powerstation.
Manapouri Hydroelectric Powerstation
Kaimai Hydroelectric Powerstation.
Kaimai Hydroelectric Powerstation
Wheao Hydroelectric Powerstation.
Wheao Hydroelectric Powerstation

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Capability Statement

Reference Project
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