UPDATED 10/04/11 12 noon

CHICAGO (CBS) — Chicago Transit Authority president Forrest Claypool says the agency is doing what it can to end the rampant employee absenteeism that can lead to long waits for passengers.

As WBBM Newsradio’s Regine Schlesinger reports, the performance data analysis by the Chicago Tribune finds the problem is worst on Mondays and Fridays, when the Chicago Transit Authority has had to cancel runs for buses and ‘L’ trains.

LISTEN: WBBM Newsradio’s Regine Schlesinger reports

The CTA cites a manpower shortage as the most common reason for canceled service.

Claypool blames the union contract for the problem.

“There are work rules that are just absurd,” he said.

Within the contract restrictions, Claypool says the city is doing what it is within its power to end chronic absenteeism. He says the agency is looking to reward workers who routinely show up.

“We want to reward those hardworking employees who stand by our customers every day, not the ones who game the system with the help of ridiculous union work rules,” Claypool said.

Claypool says it is costing the CTA $40 million this year to call in fill-in workers when the regularly scheduled bus and train drivers are out.

The Tribune analysis said the the greatest number of canceled runs likely caused by absenteeism between January and August were on No. 86 Narragansett-Ridgeland bus route, an outlying route that runs from Devon and Milwaukee avenues on the Northwest Side to the Ridgeland Green Line stop in Oak Park.

But several lines that run into downtown and serve densely-populated lakefront or Near West Side neighborhoods also stood out for missed runs, including the No. 66 Chicago Avenue, the No. 151 Sheridan, and the No. 22 Clark the Tribune reported. The No. 82 Kimball-Homan, serving the West and Northwest sides, also made the list.

Among train lines, the Blue Line suffered the greatest number of missed runs, with nearly 1,000 between January and August, the Tribune reported. The Red Line – the system’s busiest – was also cited for missed runs, with 873 in the time period.

The Tribune says Blue Line trains running from O’Hare to Forest Park were canceled most often between 7 and 9 a.m. and between 3 and 5 p.m., and buses were hardest hit between 6 and 8 a.m. and between 2 and 5 p.m.

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