It’ll have to rain a lot harder before Denver’s new anti-flood infrastructure jumps into action
The City Park Golf Course detention area and Globeville Landing outfall projects help when it pours, but recent storms were too small to trigger the big guns.
It’s really been coming down out there lately, but not enough to require the city’s new drainage system to perform heavy lifting.
The city has spent millions on drainage projects to protect Denver’s largest flood-prone area, the Montclair Basin, from dangerous waters. Crews have reconstructed City Park Golf Course to double as a water retention area. In north Denver, a mammoth underground tunnel now spits floodwaters out at Globeville Landing Park and into the South Platte River. Now Denver Public Works is working on the 39th Avenue Greenway flood channel.
The new infrastructure has handled only small trickles so far, according to Bruce Uhernik, Denver Public Works stormwater engineer. And while the drainage components have done their jobs removing pollutants from the water before it hits the river, according to Uhernik, Denver has not really required the services of the mega-infrastructure.
“Honestly, the storm that hit Saturday was the biggest one this year and was a small-to-moderate event,” Uhernik said.
There simply wasn’t enough rain to overwhelm most city streets — even if the water overwhelmed some travelers — which are designed to drain water but can hold about a foot of it. Plus, the worst of Saturday’s storm hit northwest Denver, a different flood basin.
Denver’s suite of four projects known as “Platte to Park Hill” are meant to protect locals — and the Colorado Department of Transportation’s sunken I-70 freeway in the future — from a “100-year storm,” or a rare storm that has a 1 percent chance of occurring in any given year. Uhernik called Saturday’s rainfall a “two-year storm.” It would need to rain three times as much to make the new flood infrastructure necessary, he estimates.
Locals have questioned the city’s agenda on Platte to Park Hill projects from the onset.
Their connection to the Colorado Department of Transportation’s I-70 expansion ruffled the feathers of activists who were fighting to stop the project, which displaced 56 homes and 18 businesses, on environmental justice grounds.
“There has never been flooding in our area, contrary to (Denver Wastewater Management),” City Councilwoman Candi CdeBaca told Denverite, referring to Elyria, via text message. CdeBaca led the fight against the I-70 expansion.
Locals also protested the killing of hundreds of trees at the golf course. Crews have since planted new saplings.
The Globeville Landing project included stirring up contaminated soil, prompting people to investigate via drone.
Saturday’s storm wasn’t devastating, but it was nothing to spit at either.
“An inch or an inch-and-a-half is a significant storm, I don’t wanna downplay that,” Uhernik said. “It’s notable but it’s something that is not unusual.”
The Denver Fire Department made four water rescues Saturday — one with a boat — according to data provided by DFD.
Flash floods can occur all over the city. And while problem spots exist, unpredictable storms and inconsistent drainage infrastructure means emergency responders are left guessing, said DFD spokesman Captain Greg Pixley.
“We are not an organization that has the ability to go pre-plan to be in a specific area and just sit there because we think it’s going to flood,” Pixley said. “What if the storm cell moves to a different direction, or what if there’s another emergency closer to the station?
“It’s important to the fire department to plan for the worst and hope for the best.”
Correction: This story has been edited to fix an incorrect definition of 100-year storm.