Why snow may not be plowed for a while? 17 January 2016, Baltimore

My friends keep complaining about snow removal, so I started thinking about the numbers needed and I obtained the miles of roads and number of snow plow operators from Baltimore City government web pages.

Assumptions: 

•      The Baltimore City Roadway Maintenance group maintains and preserves 2,000 miles of roadways and 800 miles of alleys. 
•      In 2010 the city had 230 snow plow operators.
•      How fast was the snow falling? 25 inches in 30 hours, about an inch per hour.
•      Each operator is capable of working for 30 hours straight.

A very optimistic estimate of snow removal is:

If a plow clearing 6" inches of snow moves 10 miles per hour then one plow could clear 2000 miles of 6 inch snow in 200 hours.

230 plows in 9 hours.  

Just a path down the center of each street.

I don't account for the accumulation that occurs during plow time, from 6" at the beginning to 15 inches at the end, the plows would become slower and slower as their journey moves on.

After all the 230 plows have made their first pass through 2000 miles of streets, and return to their starting points 9 hours later, they would be facing >9 inches on the second pass, maybe 5 mph?

The second pass would take about 18 hours. The storm is almost over, but when they get back to their starting points for round 3, it may be 18 inches of snow. Rate of progress may be only 1 or 2 miles per hour?

So I am not surprised that all the side streets aren't cleared yet. 

And the snow plow operators deserve a break after plowing for 30 hours straight.