The cost-effectiveness of integrated vegetation management

2018 | John Goodfellow, Bio-Compliance Consulting, Inc.

The Cost Efficiency of Integrated Vegetation Management (IVM)

There are 450,000 miles of transmission line operating at 35-765 kV across North America, with a total land area being managed as electric transmission rights-of-way (ROW) estimated at between 9-11 million acres. There are an additional 306,000 miles of natural gas and liquid petroleum pipeline in North America, representing an estimated 2 million areas of land. The researchers believe that less than half the total land areas in ROW is currently being managed under an IVM regime.

A project team led by John W. Goodfellow, and including SUNY College of Environmental Science and Forestry professors Chris Nowak Ph.D. and John Wagner Ph.D., recently completed a project that defined the economic business case for IVM on electric transmission ROW. The scope of that project applied least-cost economic analysis methods that focus exclusively on the direct cost to the utility of IVM practices. That approach limited any consideration of the benefits of IVM to simply avoided cost. However, indirect costs and benefits of IVM are important considerations.

The project being proposed will supplement the least-cost project, broadening the assessment to include consideration of the many benefits of IVM, and will result in a more holistic assessment that includes both economic considerations and environmental externalities associated with IVM. This will be accomplished by applying a cost-effectiveness analysis method to empirically combine monetary costs of a management action with outcomes produced from that action that can also be quantified, but that are not easily monetized. The project will also update and broaden the focus of the original least-cost study to include application of IVM methods on pipeline ROW. The goal is to produce a reference that will be useful to practitioners in selecting the least-costly and most beneficial ROW vegetation management techniques from a longer-term perspective of sustainability.

Carolyn Mahan, Ph.D., (Penn State University) and Phillip Charlton, Ph.D., will be collaborating with Mr. Goodfellow and Dr. Nowak for this expanded study.

Project Conclusion:

This project confirms that a ROW vegetation management strategy based on the principles of IVM less costly than a strategy that makes no use of herbicides but relies simply on repeated mechanical and manual treatments. The present value of cost over a 20-year evaluation period were shown to be approximate half as much as simply controlling incompatible trees by cutting without the use of herbicides over the same time period. The cost advantage of the IVM-based strategy considered in the project also was shown to provide significant benefits that would accrue top the vegetation manager, utility and environment. These benefits do not come at an additional cost.

Industry Standards 38 and Best Management Practices 39 for IVM should be adopted and incorporated in management programs used by utilities to preserve the function of electric utility ROW. The ROW Stewardship Council’s IVM “Accreditation Requirements” (2016) defines IVM principles and practices for ROW in greater detail. These references should guide management of vegetation on electric and gas utility ROW and used be used to develop vegetation maintenance specification that establish requirements and practices used to maintain ROW vegetation in a manner consistent with intended use of the ROW.

Project conclusions based on economic analysis:

The analysis work completed in this project demonstrates that a vegetation management strategy based on the use of IVM, which includes integration of mechanical and herbicide-based prescriptions, is consistently and convincingly less costly than repeated treatments using only manual and mechanical techniques. This hold true in all situations: when the efficacy of mowing was exaggerated; when the efficacy of herbicides was minimized; when the cycle length was shortened or lengthened; and when action thresholds based on MVCD were used. In addition to lower costs, the IVM strategy demonstrated lower risk (i.e., lower maximum height) between treatments.

Establishing an IVM program does require an early investment in the form of a treatment during or shortly after initial clearing by mechanical means. Although initially more expensive, the higher cost of the mechanical option inverts the relationship by the time of the first scheduled treatment and IVM becomes the low-cost option.

For more information on this project, contact the researcher via TREE Fund at treefund@treefund.org.