PHOENIX — Think twice before you toss that wrapper out the window: You may be keeping Arizona roads flooded longer during a monsoon storm.
When storms hit the Valley, rainwater that falls on freeways typically ends up at a pumping station, but so too does trash and other debris left on roadways.
“Pieces of Styrofoam wind up blocking the grates along the freeway and that winds up slowing the water getting even toward the pump station,” Arizona Department of Transportation spokesman Doug Nintzel said.
Each station varies, but Nintzel said stations are usually powered by very large pumps that push thousands of gallons of water from a collection area beneath the freeway to a nearby reservoir or the local drainage system.
“We have a total of 59 pump stations along the Phoenix-area freeway system,” he said.
But when trash gets caught up into the system, those items can also end up in reservoirs or the local drainage system. Metal grates are used to protect drainage systems, but Nintzel said those aren’t enough.
“The grates are here to stop the bigger things from getting through to the pumps,” he said. “You’re not going to stop all things.”
Trash can affect sensor systems inside the wells and can also slow down the efficiency of the pump stations. Nintzel said the threat of blockage is one reason why ADOT encourages people not to litter.
“We’re always asking folks, don’t litter, because those Styrofoam cups and other debris; they have to go somewhere and a lot of times they wind up in the wells of our pump stations,” he said.