Maintenance and Upgrades: Keeping Infrastructure Reliable

Infrastructure maintenance encompasses routine activities preventing small problems from becoming major failures. Pole inspection programs examine structural integrity on 5-10 year cycles, more frequently in severe environments. Visual inspection identifies external damage—woodpecker holes, vehicle impacts, or decay. Sounding with hammers detects internal voids. Sophisticated methods like resistance drilling measure remaining strength. Treatment extends pole life—external wraps prevent wildlife damage while internal treatments stop decay. This proactive maintenance costs far less than emergency replacement after failures but requires sustained commitment across decades.

Conductor maintenance focuses on maintaining current-carrying capacity and mechanical integrity. Infrared inspection from helicopters or drones identifies hot spots indicating damaged strands or poor connections. High-resolution cameras detect broken strands invisible from ground level. Corona cameras reveal electrical discharge from sharp points or contamination. When problems are found, crews might re-tension sagged conductors, replace damaged sections, or install repairs sleeves. Some utilities use robotic crawlers traveling along conductors for detailed inspection. Live-line maintenance techniques allow repairs without outages, using insulated tools and procedures protecting workers from energized equipment.

Underground cable testing and maintenance prevents failures through condition assessment. Partial discharge testing detects insulation breakdown before complete failure. Very low frequency testing stresses cables at reduced voltage, identifying weaknesses without causing damage. Online monitoring systems continuously measure partial discharge, temperature, and load. When deterioration is detected, options include replacement, injection rejuvenation, or accepting risk until failure. The challenge lies in optimizing limited maintenance budgets across thousands of cable segments with varying conditions and criticality. Predictive analytics increasingly guide these decisions using historical failure data and real-time monitoring.

Vegetation management represents the largest controllable maintenance expense for most utilities. Comprehensive programs include routine trimming cycles, hazard tree removal, and herbicide application. LIDAR technology revolutionizes vegetation management by creating detailed 3D models showing conductor positions and vegetation encroachment. Growth rates vary with species, climate, and conditions, requiring local optimization. Customer communication proves essential—explaining reliability benefits of proper clearances while addressing aesthetic concerns. Some utilities offer free tree replacement programs, removing fast-growing problematic species and planting appropriate alternatives. Despite billion-dollar investments, vegetation remains the leading cause of preventable outages.

Infrastructure upgrades modernize aging components and expand capacity for growing demands. Reconductoring replaces old conductors with modern designs carrying more current at higher temperatures. Structure reinforcement strengthens poles and towers for increased wind or ice loads. Voltage conversions upgrade distribution systems from older standards like 4 kV to modern 12.5 or 25 kV, improving capacity and efficiency. These upgrades require careful planning to maintain service during construction. Temporary lines might parallel existing routes during rebuilding. Mobile substations provide interim service. The logistics of upgrading energized infrastructure while maintaining reliability challenges even experienced utilities.

Climate adaptation drives new infrastructure requirements beyond traditional design standards. Higher ambient temperatures reduce equipment ratings just when air conditioning peaks demand. Extreme weather events exceed historical parameters used for infrastructure design. Sea level rise threatens coastal facilities. Wildfire risk requires new materials and operational practices. Utilities must essentially redesign infrastructure for future conditions rather than historical experience. This includes stronger structures for higher wind speeds, submersible equipment for flood zones, fire-resistant materials in wildfire areas, and expanded cooling for higher temperatures. These adaptations cost billions but prove essential for maintaining reliable service as climate impacts intensify.