(Best Management Practices)
Electric utilities and transportation departments (DOT) are charged by state and federal regulatory agencies with the responsibility to provide safe, reliable electric service and highways to their customers. Transportation and electricity is essential for domestic use, economic growth, providing for national security and other vital services. To meet these demands the pathways or rights-of-way (ROW) for the flow of electricity and transportation must be kept open and secure at all times.
Trees and other vegetation can cause interruptions of service by growing into or falling through power lines. A loss of service is not only costly and inconvenient to customers it can sever vital national security links and be life threatening to people on life support systems and in other vulnerable situations. For many utilities, tree caused power outages rank among the leading causes of interruptions of electric service during both normal-operating conditions and during major storm events.
Properly maintained DOT ROW is essential to provide for the safety of both the driving public and utility workers. Unimpeded access through ROW for inspection and maintenance of facilities and for the ultimate safety of the public is vital.
The goal of ROW vegetation management programs is to provide for the safe transmission and distribution of electricity and use of roads, streets and highways. This must be accomplished, to the greatest extent possible, while maintaining a harmonious relationship with adjoining land uses and the environment.
INTEGRATED VEGETATION MANAGEMENT
Most utilities and transportation departments apply a combination of control methods to provide for ROW vegetation management using a process termed “Integrated Vegetation Management” (IVM). IVM describes a methodical process for controlling vegetation:
- Problematic species are identified
- Action thresholds are considered
- Various control options are evaluated
- Selected control(s) are implemented.
Control options may include fire, biological, chemical, cultural, manual, or mechanical techniques. The choice of control option(s) is based on effectiveness, environmental impact, site characteristics, worker and public health and safety concerns, and economics. IVM also frequently includes prescribed burning. However, fire is difficult to control along a linear corridor and since smoke can create a path to ground, potentially shorting out high voltage lines and creating visibility problems for road ROWs, prescribed burns should not be applied to utility rights-of-way.
The desired outcome of IVM is the development of lush and stable shrub/grass/forb communities that do not interfere with overhead power lines or roads, pose a fire hazard, and/or hamper access. With proper selective management, the low growing vegetation can eventually dominate the ROW and inhibit the tall growing vegetation, thus providing cultural and biological control of the incompatible species and reducing the need for future treatments. Other benefits include reduced erosion, enhanced plant diversity, and the establishment of a sustainable supply of forage and cover for wildlife as well as corridors for wildlife movement and wildlife viewing opportunities. The establishment of native vegetation will also reduce the invasion of noxious weeds into the corridor.
A well-managed utility corridor is truly ecosystem management that can convert a fragmented landscape to a habitat-enriched ecosystem, or create habitat connectivity between ecosystems, by utilizing IVM technologies. IVM can create old-field or meadow ecosystems of low growing plant communities that have become rare and thus provide for the natural habitat necessary for the survival of rare and endangered plants and animals.
Best Management Practices
Best management practices will be used for prevention and suppression of undesirable plant species. These include but are not limited to:
- Fire, which controls unwanted tall species and allows desirable low growing plants to dominate the ROW
- Biological methods, where desirable low growing plants and animals suppress the growth of unwanted trees through their respective use of competition, allelopathy and seed consumption by small animals.
- Manual and mechanical cutting, where wood debris can be left on site to enrich the soil.
- Chemical herbicide for the treatment of incompatible tall growing trees and vines to stop their growth and remove them from the ROW.