Irrigation crews step up efforts as pests clog canals
An explosion of tumbleweeds this year is clogging up irrigation canals, sometimes blocking the flow of water completely.
Irrigation crews have been spending a lot of time clearing clogged intakes and removing the nuisance from under low bridges and along canal curves.
“For some reason, they are a real problem this year,” said Ken Curtis, an engineer with the Dolores Water Conservancy District. “We’re spending more time than usual clearing out our canals.”
The district retrofitted equipment to handle the mess. An ingenious traveling screen system works to remove tumbleweeds and debris from canals.
Spikes were welded onto a moving screen to pick up floating and drowned weeds in the canal. The device then drops the captured weeds onto a conveyor belt that dumps them to the side.
The huge piles are burned when conditions are good. The screen also filters out pond weed and algae.
“It had been piling up at Ruin Canyon so much it was starting to erode the banks,” said Gary Croke, an DWCD electrician on tumbleweed patrol. “I’m going there next.”
Crews deploy a boom truck for larger blockages. The crane was modified with giant tumbleweed “salad tongs” that can pick up large loads and pile them for burning.
To prevent loss of water through seepage, some canals have also been lined with a durable propylene membrane provided by Simbeck and Associates, of Mancos.
“They’re durable, last a long time and work well for sections with seepage problems,” Curtis said. “We’re lucky to have a local company that provides them.”