Vacuuming up drainage system litter and sludge
Vacuuming up drainage system litter and sludge
Much like cleaning your home, keeping a highway clean is a never-ending job. But in the world of freeway maintenance, we have a tool more effective than any broom or feather duster: the mighty hydrovac.
Contractors working for ADOT routinely operate sweepers on highways, after crews make their rounds picking up items that are too big for the shoulder sweepers to handle. Maintenance crews also invest a significant amount of time in preventing the buildup of trash, debris and unwanted vegetation, along our freeways.
But the work doesn’t stop there.
Inevitably, debris and trash left by litterbugs – stash your trash, please – finds its way into drainage systems, where it doesn’t belong. With about 30,000 drains and 7 million feet of pipe across the Phoenix area alone, keeping them clear is no small task.
That’s where the hydrovac enters the picture. Like a household shower drain, when a freeway’s drains get clogged, that can lead to standing water. To keep pumphouses and the drainage system clear and free-flowing, ADOT’s hydrovacs flush and then vacuum out all the sludge, muck and debris, so pumps can more easily move about 12,000 gallons of water per minute, which can happen during heavy monsoon rains.
Thirty-ton hydrovac trucks hold about 1,500 gallons of freshwater to flush out the sludge from drainage culverts and pump stations. There are more than 50 pump stations along freeways in the Phoenix area, designed to remove runoff and limit standing water on the pavement during and after storms. A hydrovac can also store about 3,000 gallons of liquid, dirt and debris that it vacuums out of a pump station’s drainage “wet well” area..
In 2022, crews removed a whopping 832 tons of debris – that’s more than 1.6 million pounds – from drainage infrastructure.
However, that’s still a process that demands a considerable amount of human effort and resources. That’s why it’s important for you and other motorists to cover loads in truck beds or trailers and not toss trash out the window. This debris often winds up in the drainage system. It can block drainage grates or pipelines, creating trouble before a hydrovac crew is scheduled to get to it. Please keep that in mind as we head into a new year and its seasonal storms.