Wildfires in the Hudson Valley: What Are the Risks? (part 1)
The Highlands Current, May 31, 2024
Some residents would see the smoke and assume it was morning mist. Others would smell it and wonder if they had missed an air-quality alert. Many would hear the sirens and spot the helicopter buzzing between river and woods, water sloshing over the sides of a 200-gallon bucket.
A few people would not realize anything was amiss until they received an automated text urging them to evacuate — assuming fire wasn’t blocking their escape.
Given last year’s soggy summer, the threat of a deadly wildfire may seem remote. New York doesn’t have the same risks as the bone-dry scrublands of California and Colorado or the boreal forests in Alberta and Quebec. But there are risks, especially with global warming rapidly changing conditions on the ground.
That’s because the Highlands is a perfect example of a “wildland-urban interface,” which the Federal Emergency Management Agency (FEMA) defines as a boundary or zone at which human development meets “vegetative fuels.”
Think of the unpaved backroads of Garrison, the homes tucked deep in the Nelsonville woods and the forest-bound neighborhood of Beacon Hills. Precisely what makes living in the Highlands so special — its proximity to expanses of protected nature — is also what could make a wildfire so dangerous.
The August wildfire on the island of Maui was the third-deadliest in U.S. history, with 101 deaths in Lahaina, a seaside town about the size of Beacon. Over the course of a few horrific hours, a brushfire started by a downed power line ripped through the town, fed by 70-mph winds.
Temperatures in Lahaina rose to 1,000 degrees — hotter than the surface of Venus — vaporizing victims. More than 7,000 residents abandoned their homes and 2,200 structures were destroyed or severely damaged. Four thousand vehicles were incinerated, leaving streaks of molten aluminum trickling down streets. Firefighters could not draw water from hydrants because the water system collapsed.
The Lahaina fire fed on changes in the landscape that took place over decades, both natural and manmade, such as agricultural irrigation systems that dried out the land. When plantations closed, the terrain was colonized by non-native, highly flammable grasses. Years of warnings about the risk of a devastating wildfire went ignored.
These types of changes have no analog in the Highlands. Our deciduous hardwoods are far less fire-prone than the grasses and conifers that cause so much trouble in Hawaii, Australia, Greece and Canada. While droughts seem to be getting more frequent and more intense, even the worst dry spells here pale in comparison to the desertification of much of the West.
Nevertheless, local emergency responders and forest rangers have concerns. Thousands of oak and ash trees, killed by invasive pests such as the emerald ash borer and the hemlock woolly adelgid, have become 30-foot-tall, 3-foot-thick kindling.
In September 2019, Hank Osborn of the New York-New Jersey Trail Conference, who grew up in Garrison, was crossing the Newburgh-Beacon Bridge when he spotted smoke rising above Sugarloaf Mountain.
Evan Thompson, the manager of the Hudson Highlands State Park Preserve, saw it around the same time as he drove south from Dennings Point in Beacon. Thompson and others went up the mountain, but they didn’t have the right tools. They came back the next day, along with rangers from the state Department of Environmental Conservation, which is responsible for fighting wildland fires.
The blaze, which likely started at an illegal campfire, had grown substantially overnight. State parks employees, DEC rangers and volunteers used heavy rakes, pickaxes, hoes and shovels to clear a 10-foot-wide firebreak around the base of Sugarloaf — a standard method meant to deprive the fire of fuel.
But after a dry summer, the fire burned into tree roots, raising the risk that it could emerge on the other side of the firebreak. That meant the team had to not only clear the surface but dig trenches — tough work on the slopes. Meanwhile, a DEC helicopter scooped water from the Hudson and dumped it on the flames.
The firebreak seemed to be working. But when the flames spread close to a cluster of homes along Route 9D on the northwest shoulder of the mountain, the firefighters had to “back burn,” intentionally burning everything between the break and the fire, a tactic designed to deprive the blaze of energy before it reaches the line.
The firefighters were able to stop the Sugarloaf blaze, largely because it was not windy. That was not true the next time a major fire broke out in the park, six months later, just as the coronavirus began running rampant.
March 9, 2020, was warm and gusty. That afternoon, the diesel locomotive of a Metro-North work train cast off embers that ignited the scrubby grasses near Breakneck Ridge. The flames scorched several parked cars, then ran across 9D and up the hillside.
Early spring can be as dangerous for fires as summer and fall. Bare branches mean the sun hits the leaf litter on the forest floor and dries it out. But because the ground is moist from snowmelt, spring fires have a hard time spreading underground into the roots and rarely grow hot enough to burn living trees.
Still, the Breakneck fire burned through nearly 300 acres before firefighters from 16 municipalities and state agencies contained it.
These incidents demonstrate the risks of wildfires but offer reassurance: They can be contained. A few factors worked to mitigate the damage, including that each fire occurred in a fairly accessible part of the park. While the Sugarloaf fire burned into the ground, making it harder to eradicate, the middling winds kept it from spreading. The Breakneck fire, though it spread rapidly, happened in the spring, when it wasn’t hot or dry enough to become an inferno.
Had the train ignited a fire in the late summer or fall, it might have been a different story, says Thompson.
In a statement, a Metro-North representative says that, after the Breakneck fire, the agency “took steps to prevent such incidents, including enhanced maintenance and testing of diesel locomotives.”