Philip runs into an alley away from the cop in episode 1x01 "Travelers". In Marcy's memories, Vincent's goons drop Marcy in an alley and she wanders around until she runs into David. Back in the present day, Marcy meets up with David and kisses him in episode 2x10 "21C". Marcy drops Simon off in the alley with a bag of supplies and her number in episode 2x11 "Simon".
Liv has a vision of zombified Blaine attacking a man in an alley in pilot episode.
Major drinks a can of Max Rager from his trunk so he can outrun the police in episode 2x11 "Fifty Shades of Grey Matter". Ravi stops Janko from kidnapping Liv from the morgue in episode 2x18 "Dead Beat". Harley Johns brings Ravi out into the alley where he is holding Don E in the back of his van in episode 3x09 "Twenty-Sided, Die".
A trash collector finds the bodies of two thugs while picking up the trash in episode 2x09 "Cape Town".
Source: YVRShoots — Twitter
The police find the body of Katty Kupps hidden behind a dumpster in the alley in episode 3x12 "Looking for Mr. Goodbrain, Part 1".
Kiera corners Lucas in an alley and then gets him arrested by the police in episode 1x01 "A Stitch in Time".
The Liber8 crew attack a pair of police offices are steal their stuff in episode 1x01 "A Stitch in Time".
Kiera sees a news report of Detective Linda Williams in Portland and assumes her identity in episode 1x01 "A Stitch in Time".