Estimated read time: 2-3 minutes
Keith McCord Reporting Ten days ago the skies opened up on Farmington. Heavy rains brought down mud and rocks into one neighborhood, but what a difference now!
While there are still sandbags lining some of the streets and cul de sacs, things are looking a bit better and cleaner.
Long before those rains hit Farmington, geologists and engineers made a decision that may have saved several houses from a lot of damage. They looked at an area where they thought there might be a problem, and took action. They built some simple barriers in a ravine, and those barriers kept the big rocks from coming down.
The sediment fences, or debris fences, are visible above the neighborhoods, stretched across a small ravine. They’re made of reinforced plastic, anchored into the ground with metal stakes.
When the rains pounded the hillside the night of April 6th, mud and rocks started coming down from high above. Some debris did make it into the cul de sac, but these fences slowed the flow.
Bronson Smart, Natural Resources Conservation Service: “It held back a lot. It held most of the storm. That’s why we didn’t have the damage here like we had on the other side.”
Following last July's huge wildfire above Farmington, engineers identified areas where slides might occur, should heavy rains fall. They spotted this area and installed the fences.
When the mud and rocks come down, it hits the fences and backs up, and creates a natural mud dam. So the next time it rains, it'll be held back.
This approach to slowing down rocks and debris has been used for years in Utah, after fires have destroyed the vegetation. They were built following the Emigration Canyon fire in the 80's and after the more recent wildfires in Santaquin and Springville.
Bronson Smart, Natural Resources Conservation Service: “In the Emigration fire we learned that the first two will get blown out completely, and then the next six will hold. That’s why we place them in series like this, is because the first slow down the stuff, and as it builds it’ll hold.”
The fences are for minor debris flows. They would not have worked in the spots where the major mudslides came down in Farmington on the 6th. But, for a temporary fix, in areas where vegetation has been burned out, they do work. And the residents living below these fences will attest to that!