BC Hydro (Canada)

Abstract Corrosion of galvanized steel transmission poles and lattice towers is a growing concern for electric utilities worldwide. This paper documents the design, implementation, and performance of system-wide impressed current cathodic protection (ICCP) programs successfully deployed at multiple utilities. Unlike localized retrofits, the system-wide approach distributes protective current along an entire corridor of structures by bonding through overhead ground wires and integrating copper substation grids with perimeter or deep-well anode beds. The results demonstrate effective polarization of galvanized structures, simultaneous protection of copper grounding systems, and significant extension of service life in corrosive soils. This paper presents background on galvanized steel corrosion, risk assessment methods, ICCP system design details, field performance observations, and lessons learned. The findings provide a framework for utilities considering similar system-wide corrosion mitigation strategies.

Abstract Coating degradation in galvanized steel transmission and distribution (T&D) structures is a gradual but critical process that affects the long-term reliability and integrity of utility assets. Unlike bare steel, galvanized steel benefits from a sacrificial zinc coating that deteriorates over time through electrochemical and environmental interactions. Understanding these mechanisms is essential for accurate condition assessment, proactive maintenance, and effective life-cycle management. This paper outlines the multi-stage degradation of zinc coatings, emphasizing the electrochemical corrosion of galvanizing intermetallic layers (gamma, delta, zeta, and eta) and the formation of oxides, hydroxides, and carbonates of zinc. Under chloride-rich or low-pH conditions, these layers weaken, exposing the steel substrate to corrosion. A high-confidence inspection approach is presented, integrating visual assessment, coating thickness, and electrochemical potential measurements to quantify corrosion risk more accurately. A case study demonstrates the use of real-time corrosion monitoring sensors for early detection and predictive modeling of coating lifespan. Integration with Geographic Information System (GIS)–based environmental mapping enables utilities to prioritize maintenance, extend asset life, and minimize unplanned outages.

This study evaluated the cumulative effects of existing and proposed land use activities and climate change within a narrow and vital wildlife corridor considered of high value to Ktunaxa and non-Ktunaxa peoples. Cumulative alteration, degradation, and disturbance to habitat directly impacts Ktunaxa lands and waters on which the exercise of Ktunaxa rights depends. Increased access to backcountry areas are expected to substantially diminish habitat condition, increase wildlife displacement and mortality risk, and fragment wildlife populations with unavoidable population-level impacts. The effects of land use are likely to be exacerbated by accelerating climate change further limiting habitat suitability and creating additional human-wildlife interactions. This study is unique in that we applied Ktunaxa research methodology throughout all assessment stages. This iterative approach to knowledge gathering brings Ktunaxa and non-Ktunaxa together in concert with input from a diverse group of problem solvers. Further, we used this opportunity to refine our understanding of cumulative effects through a Ktunaxa linguistic perspective. Repeated interviews deepened research relationships and empowered use of Ktunaxa oral history in the evaluation of cumulative effects. Two species of key concern identified for this study were ʔaȼ̓pu (wolverine) and kɬawɬa (grizzly bear). We simulated current and future habitat condition for key values using a pre-contact baseline representing the Range of Natural Variability (RONV). The assessment presented herein considered past, current, and proposed future land use activities, with a focus on recreational interests. We found combined effects of proposed recreation developments with existing land use practices within the study area to substantially negatively impact both wolverine and grizzly bear habitat condition and population connectivity. We concluded that cumulative developments of past, current and any potential future land use that includes outdoor recreational activities in ʔamak̓is Ktunaxa must be informed by regional-scale and long-term land stewardship planning to prevent further adverse impacts and to ultimately improve the habitat conditions for ʔa·kxam̓is q̓api qapsin (All Living Things).

The overhead ground wires (OHGW) are used on power transmission lines for protecting against direct lightning strikes. In this paper, the pros and cons of having an electrically continuous OHGW are discussed and a recommended practice is concluded that shows an optimized approach to minimize the undesirable effects of an electrical continuous OHGW while maximizing its benefits. The simulation results are presented to demonstrate the significance of the issues identified with an electrically continuous OHGW and the magnitude of the undesirable effects for a new 500 kV transmission line. The optimized approach is applied to the case study and the results are presented.

As smart cities are developing worldwide, so is the concern of air pollution there. It is increasingly becoming a hot topic of concern worldwide. According to the 2023 World Air Quality Report published by IQAir, a Swiss-based air quality technology company, Bangladesh was on the top of the list of PM2.5 concentration (μg/m³) for countries, regions, and territories in descending order followed by Pakistan and India. Not only in smart cities but also in many metro cities, the air quality index (AQI) is reducing every day. Major contributors to this declining AQI include vehicle fuel emissions, fuel oil, fumes from process industries, chemical products, and many others. Today’s AI and IoT technologies however have the potential to provide solutions to many real-life problems including the problem of monitoring and controlling air pollution. AI and IOT help to control air pollution by monitoring AQI, sensors, and remote sensing. It can collect real-time data from multiple locations, which is then analyzed to identify the sources of air pollution. IOT makes monitoring easier and access to that information should be affordable to all. IoT and AI also help to detect toxic substances and fumes that may contain carbon monoxide, ozone, nitrogen dioxide, sulphur dioxide, and other toxic gases. This paper underlines the burning issue of air pollution worldwide with a focus on the smart cities of the future. Citing a few recent developments in AI and IOT technologies, it advocates that monitoring AQI, application sensors, and remote sensing can effectively contribute to ensuring quality air in future smart cities. Examples of application of these technologies in a few metro cities have also been quoted along with the scope of future research in these areas.

There are limited diagnostic testing techniques for the stator winding insulation of large hydro-generators. Some popular AC insulation tests cannot be applied to a large hydrogenerator since a large AC power source is required to energize the stator winding with a high capacitance. This challenge brings difficulty and a high cost for AC diagnostic tests for a large hydro generator. A 0.1Hz test has an AC component in its test voltage waveform that can be used to perform AC diagnostic tests on the stator winding, such as dissipation factor testing. Since VLF (Very Low Frequency) test equipment is portable, it can be easily taken to a site to perform testing. In this paper, VLF diagnostic testing was applied to a hydro-generator stator winding, such as VLF dissipation factor testing and VLF withstand testing. A comparison test between 0.1Hz and 60Hz tests was also conducted to check if a VLF test result can provide a similar one to a 60Hz test result. The paper presents the 0.1Hz and 60Hz test data, VLF withstanding test data, and condition assessment of a hydro-generator stator winding.

Climate change poses risks to society through the potential to alter peak flows, low flows, and annual runoff yield. Wildfires are projected to increase due to climate change; however, little is known about their combined effects on hydrology. This study models the combined impacts of a climate change scenario and multiple landcover scenarios on the hydrologic regime of a snowmelt-dominated montane catchment, to identify management strategies that mitigate negative impacts from climate and/or landcover change. The combination of climate change and stand replacing landcover disturbance in the middle and high elevations is predicted to advance the timing of the peak flow three to five times more than the advance generated by disturbance alone. The modelling predicts that the combined impacts of climate change and landcover disturbance on peak flow magnitude are generally offsetting for events with return periods less than 5-25 years, but additive for more extreme events. There is a dependency of extreme peak flows on the distribution of landcover. The modelling predicts an increasing importance of rainfall in controlling peak flow response under a changing climate, at the expense of snowmelt influence. Extreme summer low flows are predicted to become commonplace in the future, with most of the change in frequency occurring by the 2050s. Low annual yield is predicted to become more prevalent by the 2050s, but then fully recover or become less prevalent (compared to the current climate) by the 2080s, because of increased precipitation in the fall-spring period. The modelling suggests that landcover disturbance can have a mitigative influence on low water supply. The mitigative influence is predicted to be sustained under a changing climate for annual water yield, but not for low flow. The study results demonstrate the importance of a holistic approach to modelling the hydrological regime rather than focusing on a particular component. Moreover, for managing watershed risk, the results indicate there is a need to carefully evaluate the interplay among environmental variables, the landscape, and the values at risk. Strategies to reduce one risk may increase others, or effective strategies may become less effective in the future.

Abstract. Snowmelt runoff serves both human needs and ecosystem services and is an important parameter in operational forecasting systems. Sentinel-1 synthetic-aperture-radar (SAR) observations can estimate the timing of melt within a snowpack; however, these estimates have not been applied on large spatial scales. Here we present a workflow to combine Sentinel-1 SAR and optical data from Landsat-8 and Sentinel-2 to estimate the onset and duration of snowmelt in the La Joie Basin, a 985 km2 watershed in the southern Coast Mountains of British Columbia. A backscatter threshold is used to infer the point at which snowpack saturation occurs and the snowpack begins to produce runoff. Multispectral imagery is used to estimate snow-free dates across the basin to define the end of the snowmelt period. SAR estimates of snowmelt onset form consistent trends in terms of elevation and aspect on the watershed scale and reflect snowmelt records from continuous snow water equivalence observations. SAR estimates of snowpack saturation are most effective on moderate to low slopes (< 30∘) in open areas. The accuracy of snowmelt duration is reduced due to persistent cloud cover in optical imagery. Despite these challenges, snowmelt duration agrees with trends in snow depths observed in the La Joie Basin. This approach has high potential for adaptability to other alpine regions and can provide estimates of snowmelt timing in ungauged basins.