Earth 365: Why has there been an increase in landslides over the last few years?
PITTSBURGH (KDKA) - CBS News and KDKA-TV are committed to covering stories about the Earth and our environment all year long, but especially this week as we celebrate Earth Day today.
All this week on KDKA News at 5 p.m., we've been taking a look at our changing climate and the impact it's having on all of us in a series called "Earth 365".
In the final part of our series, we're talking about landslides.
Over the last few years, we've seen an inordinate amount of landslides in southwestern Pennsylvania.
Experts say more rain, more frequent freeze-thaw cycles and sprawling development are intensifying the issue.
We all know Pittsburgh is home to three rivers and more than 400 bridges but it's also home to countless hills, many of them steep, making this a challenging environment for a city.
"A lot of cities are laid out by grids. They're planned around geographic and topographical features. Pittsburgh was not. Pittsburgh is a city that just evolved because there were three rivers and that's where industry came," said PennDOT District 11 Executive Cheryl Moon-Sirianni.
One of those three rivers should have been a clue about what Pittsburgh's settlers were getting into by building here.
The word Monongahela means "river with sliding sides".
But our river banks aren't the only places that slide. As landslide issues have come to the forefront recently in several areas.
Especially during 2018, Pittsburgh's wettest year on record.
Allegheny County Landslide Task Force co-chair Matt Brown said, "Four times in 2018 we declared a disaster for the county, as well as all the municipalities doing the same. It was an incredible year of precipitation that really instigated all the landslides and embankment failures."
Precipitation's provocation of landslides was proven that year.
Unprecedented February rainfall, and a constant freeze-thaw cycle, lead to a landslide that wiped a home in the West End and closed part of Route 51 below it.
Not even two months later, we saw the incredible collapse of Route 30 in East Pittsburgh.
Many other landslides were noted in 2018, and their problems linger still in 2022.
"A lot of those impacts in 2018 still exist today. There are many landslides or landslide roads or embankment failures that are still impacting us today," Brown said.
"We hit the high in 2018, obviously, with the excessive rainfall. 2019 wasn't a whole lot better. So we're still playing catch up," added Moon-Sirianni.
When landslides hit a public space, there's public money available to fix the problem.
But when they hit private property, the impacts are much different. Insurance does not cover landslides, so homeowners are left paying for homes they can't live in. A situation that can become financially crippling.
Landslides take away from improving other facets of our infrastructure, too.
Moon-Sirianni said, "Every dollar you spend on a landslide is a dollar amount we're not spending on a road or bridge, and we don't get any extra money in our district because we have landslides. So just keep that in mind that you have to balance it with everything else."
However, money is going to equipment that can help with trouble spots.
"Our budget with public works has four million dollars a year to use on capital projects, and also our operations division takes care of the landslides. We also just purchased another excavator for $240,000. So they can do more work on the roads and address these landslides," said Stephen Shanley, the other co-chair of Allegheny County's Landslide Task Force.
So what can be done to stop or slow landslides from becoming a bigger issue?
"It all goes back to money and drainage. If you can get the water off the road and get it off the slopes and taken to waterways that can handle it, you're going to stop a lot of those issues," said Moon-Sirianni.
Also, changing how we interact with our surroundings is becoming a focus.
Brown said, "This is a condition that existed well before our time and it's going to continue for well past our time. So we've got to acknowledge it and do our best to mitigate it any chance we can."
For the Allegheny County Landslide Task Force, education is key to mitigation.
"What was interesting during the landslides in 2018, we looked in our emergency management files and found files dating back as far as 1975 of landslides in some of the exact same spots where we were seeing repeats in 2018. So it's really about educating ourselves about where and how to define it and to recognize it. So that hopefully we can avoid it," said Brown.
To that end, the county has created the Allegheny County Landslide Portal.
It pinpoints trouble areas and helps educate people about preventative and corrective actions when it comes to slides.
It also lets you know what you're building on and the potential impacts of stormwater run-off in that area.
And while new ways of viewing our current infrastructure are helpful, we still have to consistently monitor and deal with the landslides that are actively out there.
Brown said, "There are hundreds of them. What I can't tell you is the severity. Some of them can be very minor to relatively extreme, but it's an ongoing daily process."
Interestingly, as a side note, the three wettest years on record in Pittsburgh have occurred in the last 18 years, and five of the ten wettest have occurred in the last 32 years.
So if this pattern of wetter weather continues, it means we'll likely have to adapt to more landslides in the coming years here in southwestern Pennsylvania.
