Des Moines asks: Where were all the snow plows?

A daylong snowstorm that left as much as 6 inches of snow on the ground in central Iowa wreaked havoc on Monday afternoon commutes.

The long lines of cars trying to escape downtown Des Moines left many wondering: Where were the snow plows?

Apparently, waiting for downtown workers to clear out.

Des Moines does not plow downtown streets until after business hours, according to Public Works Director Jonathan Gano.

"There's too much traffic and too many cars on the side of the road," he said.

Plowing during the day creates piles of snow along streets and impedes access to parking meters, according to a snow-removal guide developed by the city.

On rare occasions, the city has used trucks to haul snow out of downtown. But the last time that happened was during the winter of 2012-2013.

"That is fabulously time-consuming and very cumbersome effort, plus it has an enormous impact on traffic that we are reluctant to undertake," Gano wrote.

Chris Anderson tried to beat the rush Monday by leaving his downtown office at 1:30 p.m., only to get stuck in traffic on Second Avenue for an hour.

The four-lane road — a snow route from downtown to Interstate Highway 235 — was down to one lane as vehicles, including Anderson's, got stuck on the hill.

A police officer helped Anderson push his car from Center Street to Crocker Street until it was able to find traction again.

"Why are we not getting the main roads to the interstate cleared off to get people out of downtown," he said.

The amount of snow, the timing and speed at which it accumulated "exceeded the ability of snow plows to be able to handle clearing it off," Gano said.

The city fell victim to bad timing, he said.

"There's not much a road agency can do when people start their day like normal and conditions turn upside-down," Gano said.

The already frigid temperature of the pavement made things even more difficult, he said.

Pre-treating roads with a brine mixture can help reduce ice buildup, but as temperatures dip into the teens and lower, the treatment becomes less effective.

The city began applying brine on snow routes Thursday in preparation for Monday's storm. It takes a day and a half to apply the anti-icing mixture to the city's snow routes. And it's effective for up to four days on high-traffic routes.

Laying down the brine mixture on Thursday also let the city avoid paying workers overtime over the weekend, Gano said.

Des Moines snow plows tackle snow routes before moving to neighborhood streets. The city has 17 snow routes that make up nearly 700 miles of roads.

Plows started hitting the snow routes at 9:30 a.m. Monday. But it can take four to six hours for one plow to finish a single pass. The last route was cleared at around 4 a.m. Tuesday morning, Gano said.

Once snow routes are clear, plows jump to one of the 40 neighborhood snow districts.

Twenty-five percent of the city's neighborhoods were plowed by Tuesday morning, Gano said.

"We are on track to be done within 24 hours of the last snowflake falling, which is our goal," he said Tuesday.

Des Moines Councilman Chris Coleman said it appeared his street had been plowed a couple of times by Tuesday morning.

"I haven't received any direct complaints about it," Coleman said.

Kelsey Seay spent her Monday afternoon digging out four drivers stuck near 16th Street and Allison Avenue in the Mondamin Presidential neighborhood.

School buses trying to drop children got stuck on Chautauqua Parkway. At least one bus just let kids off to walk up the hill, Seay said.

"It was a mess," Seay wrote on Facebook.