Over the course of the project, some concern has been expressed over the potential impact transmission lines may have on property values.
A project journal post from last July discussed this issue in detail and included a link to a July 24th article in the Concord Monitor focusing on the issue. The project journal post and article reference two studies Northern Pass commissioned to look at the property value impact issue.
The first was a preliminary study of the impact of an existing high voltage transmission line in New Hampshire on property values in the towns of Littleton and Deerfield by Brian C. Underwood, CRE of B.C. Underwood Real Estate Counseling & Appraisal.
The second was a review of major studies of the impact of high voltage transmission lines on property values by Russell Thibeault of Applied Economic Research
We have also previously referenced a 2008 study by James Chalmers Ph.D., an economist and real estate appraiser, that was published in a peer reviewed journal that analyzed whether high-voltage transmission lines affected the value of residential properties located in two New England states.
In each case, these studies have arrived at the same general conclusions: the presence of high voltage transmission lines statistically has little to no effect on the value of neighboring properties.
Dr. Chalmers recently authored a study (full report here; summary report here) looking at the effect of an existing high voltage transmission line on property values in Montana. Montana has unique combinations of terrain, vegetative cover and land use patterns compared to the context in which most of the existing research on property value effects has been carried out. In addition, the relevant lands in Montana are characterized by a wide variety of agricultural, recreational and residential property types with relatively few sales. The low number of sales led Dr. Chalmers to pursue a case study approach.
The Montana study focuses on 57 case studies encompassing seven property types: three agricultural, two recreational residential subdivisions and two large acreage recreational tracts. The Montana study cautions that conclusions with respect to a particular property always have to be based on the attributes that drive the value of that property and the way in which they may or may not be affected by the transmission line. With respect to the Montana case study properties, Dr. Chalmers observed that property values appear to be more immune to any effect if the use of the subject property is more diversified beyond pure residential, if the property is larger, and if there are fewer substitute properties on the market that are not situated near transmission lines. He also observed that the value of undeveloped lots in residential subdivisions (recreationally oriented) with limited flexibility in the siting of improvements and for which there were ample substitutes on the market that were not situated near transmission lines were less immune.
This same case study approach was applied in the previously cited Underwood study and it will be interesting to see how the New Hampshire findings compare to the Montana research given the differences between northern New England and the Rocky Mountain States. Like Chalmers, the methodology employed by the Underwood study was to identify an existing transmission line and analyze the assessment data and sale prices of properties that abut the line compared to similar properties not affected by the line. From the Underwood study summary:
“…Based on the preliminary analysis contained herein, there is no market evidence in either Deerfield or Littleton that would indicate diminution of property value due to high voltage transmission lines…”
2012-05-29: This post was updated to better reflect the project’s perspective.