PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Air Traffic Control Fully Certified
Communication Breakdown; Confusion; Distraction; Situational Awareness
ATC Issue All Types; Conflict NMAC
Air Traffic Control Issued Advisory / Alert; Flight Crew Took Evasive Action
Human Factors; Aircraft
I was on Local 2. The Local 1 controller coordinated a northbound [departure]. I approved the coordination outside of Aircraft Y which was just off the departure end climbing. Aircraft Y was in left closed traffic. Aircraft X turned immediately causing Aircraft Y to dive 100 ft. to miss Aircraft X.I quickly gave traffic and instructions to avoid the collision. Aircraft Y informed that there was only 50 ft. separation. I noticed Aircraft X turning and informed the Local 1 controller. He did nothing to control his aircraft or mediate the incident.This is not the first or 50th or last time this controller has not or will not control the aircraft on his frequency. He continously put aircraft in dangerous situations. He is lazy and subpar.
Tower Controller reported another tower controller wasn't doing their job correctly which led to a NMAC.