Huge Rocky Mountain snowfall provides drought relief but causes flood worries
STEVE INSKEEP, HOST:
The huge snowfall in the Rocky Mountains this winter is providing some relief after years of drought. That same snowfall is making people nervous because if it melts too quickly, major flooding is a real risk in several states. Ryan Heinsius of our member station KNAU reports on the situation in Flagstaff, Ariz.
RYAN HEINSIUS, BYLINE: Kyle House walks around his property in a neighborhood that bore the brunt of several major floods last summer, when seasonal rains washed down the San Francisco Peaks in the wake of a major wildfire.
KYLE HOUSE: So this was a river right here. We had whitewater streams coming out both sides through both gates. It was a nightmare. We had so much water coming in our yards.
HEINSIUS: The flooding created a waist-high lake in his cul-de-sac, upending he and his neighbors' lives. They quickly mobilized to stack thousands of sandbags and dig ditches to channel the water away from their homes. Those sandbags and ditches are now providing some protection should this winter's record snow melt too fast. Across Flagstaff, more than 1,500 homes are at risk.
HOUSE: We're planning our lives completely differently in the summer. It just provokes all kinds of anxiety. And that's widespread in the neighborhood, for sure.
HEINSIUS: House happens to be a research geologist who's studied flooding in Arizona for more than three decades. He sees his situation as representative of the much larger danger of wildfires and flooding exacerbated by climate change.
HOUSE: In terms of being in the Southwest, where you really are on the edge of drought almost all the time, I feel like that we are just right at the ground zero for how bad this problem can get.
HEINSIUS: Just upstream from House's neighborhood, the normally dry Schultz Creek surges with spring runoff.
ED SCHENK: I'd say Schultz, even during a regular snowmelt season, is usually a trickle. With such a great snowpack this year, yeah, it's looking a lot more like a river.
HEINSIUS: Ed Schenk is Flagstaff stormwater manager. He's standing on the rim of three detention basins the city built quickly last fall. They've been mostly containing this huge volume of snowmelt for now. The basins weren't designed for this but rather to hold back massive post-wildfire flooding.
SCHENK: This is hugely fortuitous. If we didn't have these in place, there would have been much more severe flooding impacts through this spring, especially in March when the first snowmelts were coming down.
HEINSIUS: Flagstaff received about double its average snowfall this season. Stacey Brechler-Knaggs is the city's emergency manager.
STACEY BRECHLER-KNAGGS: We're seeing a lot of impact throughout the community just from the snowmelt. It's changed, you know, since just since last week, creating some little overflow and coming in pretty fast.
HEINSIUS: Whether the basins will be enough to protect neighborhoods downstream all depends on the weather. If it gets hot too fast or it rains on top of the accumulated snow, there could be widespread flooding. Locals are hoping for a gradual melt. Lucinda Andreani leads the Coconino County Flood Control District, which is preparing to break ground on several large-scale flood mitigation projects.
LUCINDA ANDREANI: This will be the single largest set of projects the district or county have ever undertaken.
HEINSIUS: On a map, Andreani points out where the wildfire heavily scorched several watersheds. Using more than $90 million in federal funding, crews will work to prevent erosion and restore those natural channels. The projects are expected to take two or more years to complete.
ANDREANI: The work that we do on forest basically advances the recovery of the watersheds by about 75 years.
HEINSIUS: Andreani hopes enough work can be done in the near term to avoid a repeat of last summer, when residents had to shelter in place, major highways closed, and neighborhood streets turned into raging rivers. But anxiety levels are rising as communities face the prospect of another monsoon season spent behind piles of sandbags and concrete barriers.
For NPR News, I'm Ryan Heinsius in Flagstaff. Transcript provided by NPR, Copyright NPR.