RIAC plans for major tree cutting

Sat, 01/21/2023 - 11:30am

Changes may be coming to how pilots land at the Block Island State Airport. The Rhode Island Airport Corporation has just closed its 30-day comment period on a “Final Draft Environmental Assessment” for the removal of obstructions
on and around the island airport. In this case, obstructions means trees, and readers might not think of Block Island as a place where the trees grow so high that they affect planes landing, but they do when those aircraft are using a
visual approach.
In order to remove the obstructing trees, RIAC must acquire easements allowing them control over the height of trees on privately-held property. In performing its assessment, RIAC found that, in all, 22 acres have obstructions and 16
easements would be required if a “full clear” were to occur.
Most of the trees in question are around the perimeter of the airport property, and mainly in the corners, or on the hill on the western side of Center Road across from the airport. RIAC already holds an easement for tree removal on conservation land across from the airport, but additional lots just to the west and south, also have trees that are considered airport obstructions.
Some of the land in question is also conservation land, or abutting it, and the environmental assessment was on the agenda for the January 12 Block Island Land Trust meeting, which is regularly attended by partners from the Block Island Conservancy and The Nature Conservancy.
RIAC has proposed four alternatives in planning for this project. The first alternative is to do nothing. However, if that were the selected solution, there would be impacts, as the airport must comply with federal safety requirements, especially to obtain funding for improvements.
According to the environmental assessment: “There are no environmental impacts associated with the implementation of the “No Action” Alternative. However, this alternative restricts the use of the runway to day-time operations only
and could potentially restrict certain aircraft from using the runway and is therefore the least favorable of the alternatives from an operational standpoint. Furthermore, implementation of the “No Action” alternative may jeopardize the airport’s ability to obtain future FAA Airport Improvement Project funding due to the failure to honor existing grant assurances requiring the airport to maintain a safe operating environment.”
The second alternative is the “full clear.” Under this scenario, the amount of easements, obstructions and remediation costs is the highest. It involves the removal of “upland vegetation” on 22 acres, both within and without the airport. It will require 16 easements, and the cost of the project is estimated to be $435,000 to design, permit, and construct. It does not include the cost of the easements. It “rectifies existing safety deficiencies” and allows for the airport to operate as it has been.
In between are two alternatives that are slightly different. Alternative 3.A involves the removal of up to 12 acres of trees at an estimated cost of $285,000 and acquiring up to 9 easements at an unknown cost. It involves removing “vegetative obstructions” to the “Precision Approach Path Indicator Obstacle Clearance and Light Signal Clearance Surfaces (PAPI OCS and PAPI LSCS).” That might be a long, boring name, but it describes an interesting system for pilots doing visual approaches and landings at the airport. The Environmental Assessment describes it as follows:
“PAPIs are ground mounted light assemblies that provide pilots with visual slope information. The PAPI system provides the appropriate glide path to the runway touchdown point based on a sequence of horizontal red and white lights visible to a pilot on final approach. A pilot will see two red lights and two white lights when on the proper glide path. More red lights signify the pilot is below the glide path. Conversely, if a pilot sees three white lights and one red light for example, their course is above the glide path to the runway. The PAPI system has associated air surfaces (including the OCS and LSCS) that must be maintained free of obstructions in order for a pilot to correctly interpret PAPI light signaling.”
Currently, the lights are set up to enable a standard three-degree glide path for runways 10 and 28. For “utility runways without jet aircraft operations such as the runway at Block Island Airport, the glide path angle may be more than three degrees but not more than 4.2 for obstacle clearance requirements.”
Most think of the Block Island Airport as only having one runway, but it has a different name depending on which direction a plane is approaching from. If one is coming from the west, it will land on Runway 10. If it is coming from the east, it will be landing on Runway 28.
While alternative 3A maintains the three-degree glide path going both directions, alternative 3B tweaks it such that the number of required easements falls to five, covering 4.2 acres, at a cost of $185,000. Adjusting the lights and the glide path up to 3.5 degrees “effectively removes all obstructions and from the Runway 10 PAPI OCS and LSCS, resulting in approximately four acres of upland vegetation obstructing the Runway 10 approach to be removed.”
All of the five parcels identified as needing easements under plan 3B are on the western side of the airport. One is owned by the Block Island Conservancy, and one by the Block Island Land Trust.
The additional 0.2 acres are approximately 150 feet south of the end of Runway 28, which is on the eastern side of the airport. It’s very close to the Boy Scout camp, where there are old-growth, native trees including American beech and black gum. There also appear to be oaks in the area. The Nature Conservancy bought the development rights several years ago. TNC Associate State Director Scott Comings said the trees to be removed in the area were predominantly black cherry and that he had walked the area with those who performed the assessment.
Comings said he was most comfortable with the last alternative, 3B, as were the others at the meeting. Land Trust Chair Barbara MacMullan said that their comment on the assessment should “include that if 3B isn’t chosen, the Block Island Land Trust would like to revisit it.”
Tree removal, no matter which alternative is chosen, would occur between Nov. 1 and May 1 to “avoid impacts” to the northern long-eared bat (Myotis septentrionalis) and the American burying beetle (Nichrophorus americanus). The period of time has been chosen as bats are hibernating then, and the beetles are dormant underground. However, to mitigate damage to the soil where the beetles may be, tree trunks must be carried, instead of being dragged across the ground or using skids. In forested areas, trees will be cut to ground level and the stumps left. On residential properties, the stumps may be removed. RIAC plans to perform the work in 2024.
It should be noted that the concern around bats is more general than specific to Block Island. There are no known populations hibernating in the area, however, the overall population of this and other types of bats has declined precipitously in the past few years, primarily due to “white nose syndrome,” a fungus, that was discovered in a New York cave in 2007.