Arlington’s pub crawls may soon be less freewheeling. The county is preparing to create regulations that will require special events permits before bars can hold the popular and controversial events.

The County Board on Saturday will vote on whether to change its events policy to require taverns to get a permit to hold the open-air parties likely to attract more than 500 patrons. Bar or pub crawls encourage patrons to travel from one business to another, which offer special-priced drinks during a set period of time.

If, as expected, the board members approve the change, bars could be charged for police patrols and trash cleanup. The county manager will then issue regulations that govern how much the businesses will be charged.

Arlington police and some residents say the bar crawls are out of control. A St. Patrick’s Day party attracted about 5,000 revelers and led to 25 arrests, and a naked man crashed his car and had to be tasered into submission during a June bash.