on podiums

年末から新年にかけてのholidaysには、警察はどこも大忙しですね。at street level and on podiumsとはどのような意味なのでしょうか。ゼミ生のTo To Toくん、どうぞ。（Sugiuchi）
Police and ambulance services across the country were in high demand on New Year's Eve dealing with a string of incidents as revellers saw in the start of the Olympic year.

Scotland Yard had 3,000 officers on duty, both at street level and on podiums in London, to give them a bird's-eye view of any troublemakers in the crowds.

The force said the total number of arrests for the night was 77, mainly for assault and drunk and disorderly offences.

Meanwhile, the London Ambulance Service said it experienced a busy night, receiving calls peaking at 600 an hour - the average is usually 180 calls an hour on a normal night.

During the night paramedics treated 274 patients, taking 55 of them to hospital.

http://www.independent.co.uk/news/uk/crime/police-in-highdemand-on-busy-new-years-eve-6283895.html