Environmental Effects of Underground & Overhead Transmission Line Construction & Maintenance in the United States Ryan A. Brockbank Halifax, Nova Scotia September 20 23, 2015 Environmental Concerns on ROW Management 11 th International Symposium
Electric Power Research Institute (EPRI) John Goodrich-Mahoney, EPRI Project Manager Ryan Brockbank Kevin McLoughlin ECI Principal Investigators Lynn Askew Heather Harder Wendy Hosman Power Engineers Principal Investigators
The Demand For Safe & Reliable Electricity
IOUs Invest $92.9 Billion on Transmission Projected Transmission Capital Expenditures By Activity Type 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 11% 11% 10% 10% 4% 3% 2% 2% 22% 28% 26% 25% 15% 15% 16% 17% 48% 43% 46% 46% 2014 2015 2016 2017 Security Measures/Other Advanced Technologies System Improvement Line Replacement Transmission Expansion & New Build Source: EEI Updated November 2014
Overhead vs. Underground Transmission Overhead (OH) Lower Cost Higher Outage Frequency Shorter Outage Duration Faster Repair Time Underground (UG) Higher Cost Lower Outage Frequency Longer Outage Duration Slower Repair Time
Overhead Transmission Construction BPA McNary-John Day 500 kv Overhead Transmission Project
Overhead Transmission Construction BPA McNary-John Day 500 kv Overhead Transmission Project
Underground Transmission Construction PG&E s Jefferson-Martin 230 kv Underground Transmission Project Northeast Energy Link Proposed 230 Mile Underground DC Cable
Potentially Affected Resources Land Use Biological Soil & Geological Water Cultural Visual The project does not address health issues (EMFs) or air resource impacts.
Land Use Types Agricultural Forests & Wilderness Parks, Recreation & Preservation Areas Transportation & Access Developed Lands Residential Commercial Public Facilities Industrial
Effects on Land Use
Trenchless Construction HDD Frac-Out Event
Underground HDD Frac-Out Event
Effects on Land Use - Wildfire
Effects on Land Use - Wildfire
Effects on Land Use - Wildfire
Effects on Biological Resources Vegetation Effects Disruption of existing vegetation Change in habitat type or vegetation composition Habitat fragmentation Disruption of rare, threatened, and endangered species Introduction of invasive plant species
Effects on Biological Resources - Vegetation ROW corridors can enhance plant diversity Positive effect on some individual species, however Habitat generalists can thrive Replacing rare plants with common ones Invasive plant impacts on native plant species
Effects on Biological Resources Wildlife Effects Habitat and population fragmentation Habitat loss and reduced species abundance Wildlife displacement and disturbance Disruption of rare, threatened, and endangered species
Effects on Biological Resources - Wildlife Displacement vs. Mortality
Effects on Biological Resources - Wildlife
Native Pollinator Karner Blue Butterfly Early successional habitat Blue lupine is vital to the butterfly s survival Federally endangered Karner Blue Butterfly thriving on WI ROW
Effects on Soils and Geological Resources Soil erosion Soil compaction Soil profile disruption Reclamation constraints
Effects on Soils and Geological Resources
Effects on Soils and Geological Resources
Effects on Water Resources Water resource availability, accessibility, and quality Surface water Wetlands Floodplains Groundwater
Effects on Water Resources Research reported on long-term effects of an overhead transmission construction project in MA; discovered that cattail marsh and wooded wetland ecosystems completely recovered within a few years.
Effects on Water Resources
Effects on Cultural Resources Prehistoric and Historic Archaeological Resources Architectural Resources Traditional Cultural Properties 106 National Historic Preservation Act
Effects on Cultural Resources
Effects on Visual Resources New York City 1887 Vancouver, BC 1914
Effects on Visual Resources
Summary Both OH and UG transmission can have beneficial and detrimental effects on the environment UG transmission can actually have greater detrimental effects
Summary Out of 33 potential environmental impacts associated with OH vs UG transmission construction and maintenance: UG can have greater detrimental effects in 33% of the impact categories UG can have lesser detrimental effects in 15% of the impact categories UG and OH have similar environmental impact potential in 52% of the categories Site-specific evaluation and mitigation techniques determine actual relative impacts
Thank You! Questions... Ryan A. Brockbank rbrockb@eci-consulting.com