Eversource is prudent to take proactive measures to protect the grid. But their plan fails to minimize harm.
They propose to cut trees that, by their own figures, aren’t anywhere near the wires. Within 100’ of their lines, they plan to remove all species with mature heights of >30’. Trees would have to be a lot taller than that to contact wires that are up to 100’ away and up in the air. They’re proposing straight-line cut zones that neglect even basic calculations using tree heights, wire heights, and distance (let alone additional factors that the EEA certificate directs Eversource to factor in, such as topography and species’ typical heights).
They say they need access to the wires, but they already have the equivalent of 6-16 Mass Pike lanes cleared. Their proposal would increase that to the equivalent of 16-35 Mass Pike lanes. They don’t explain why their access needs are so extreme.
They’re gunning for a once-and-done, maximal clear-cutting approach. They want to cut everything all at once that could conceivably pose a risk any time over the next 40 years. Their calculations assume that all trees could grow eight feet taller than the current record-holding trees in their project footprint. This despite their own acknowledgement that “only a small number of the thousands of trees [in the LiDar survey] had existing heights close to these…”
They claim their plan follows industry standards, but their interpretation is questionable. Eversource points to FERC/NERC standards and recommendations, which do indeed say that vegetation management should be practiced across the full width of utilities’ ROWs. But they don't say to clear-cut. The FERC/NERC report recommends ensuring “that danger trees [emphasis added] are not present…” “Danger trees” are defined as “any tree that, if it fell, could contact a transmission line.” Eversource is interpreting every tree as a danger tree, even though only a subset will ever become danger trees, and an even smaller subset is a danger tree now.
Eversource conducted an alternatives analysis, but they completely excluded an obvious alternative from that analysis: selective cutting of the trees that pose an emergent risk, and favoring pruning or topping to cutting whenever possible.
Eversource is unquestionably aware of this alternative. It was called for in public comment after public comment. Eversource’s own earlier version had map legends with color-coded crosshatching for “Tree removal,” “Selective tree removal,” and “Pruning.” In this version, they deleted these categories and replaced them all with “Proposed tree clearing.”
So being selective was on their radar, and they decided against including it in their alternatives analysis. Instead, they try to spin the word ‘selective’ to mean something different. Eversource repeatedly insists that their proposal has been modified to be selective. But what they mean is that they’re still going to cut 100’-wide, straight-line swaths on each side of their already 125'-335' cleared corridor, but they’ll skip cutting six acres (out of 284 total), where they’ve determined there’s no risk. They still omit any alternative that would be selective within the cut zones.
Eversource does explain that “it is often difficult to avoid/protect compatible [trees]... that are interspersed with incompatible” ones. That’s understandable, but it doesn’t naturally follow that they shouldn’t even attempt selective management. Selective management is a common practice – even a common Eversource practice. Eversource could aim for selective management, with the understanding that of course not every non-target tree will be able to be saved.
Selective management is presumably more expensive, but instead of never analyzing it, the pros and cons should be calculated for at least two alternatives:
Selective management across the whole project.
Selective management solely in the most sensitive parts of the project, such as the riverfront and/or wetland areas, and/or the areas that are state-designated Priority Habitat for rare species.
Likewise, other alternatives that Eversource rejected as too costly (such as raising wires) could also be reconsidered solely for particularly sensitive spots.
Storms are getting worse, and Eversource is prudent to protect the powergrid. There’s a question of how wide of a corridor is wide enough, and data should guide the answer. Since the corridor is already 125-335’ wide, public comments in the previous stage asked: Have trees ever caused outages along the proposed project’s powerline corridor? Eversource’s answer is equivocating, and quite possibly means NO.
In Table 2.1 of their DEIR document, Eversource does their best to make the risk look substantial. The table lists dozens of outages “Involving Contact with Vegetation” since 2011.
But the table doesn’t convey the distance between trees and wires. It includes outages along all their MA transmission lines, and all the portions of those lines, without indicating cleared corridor widths.
Of the dozens of rows in the table, only two might be on powerlines that are part of this project. 28 of the 29.3 miles of the project are for line 354. There have been zero outages on that line. The remaining lines in this project are 1604 and 312. There have been zero outages on 1604. There have been two on “312/393.” Those outages might have been on the part of 312 that’s in the project footprint, or not, and where clearing was already substantial, or not.
If the real answer is that no outages have been caused by trees in the project’s 125-335’ wide corridor, Eversource’s reply would be a good way to obscure that. If there’s any conclusion to draw from Eversource’s Table 2.1, it’s that the substantial, 125-335’ Eversource already has cleared may well be doing its job, and may not cry out for further widening.
The EEA certificate says that Eversource’s prior proposal has “no factual evidence or documentation to show that interference with power lines is an active problem that requires ±371 acres of tree clearing.” This statement is still true, because Table 2.1 has no data about the distance between trees and wires. Given that such corridors are numerous, Eversource should provide data that demonstrates that there are benefits to further increasing the distance between trees and wires, and the point at which further widening no longer yields enough benefit to outweigh the drawbacks.