Date: 201811
Local time of day: 1201-1800
Location: C90.TRACON, IL
Flight conditions: VMC
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class B ORD
ATC / advisory: TRACON C90
Second aircraft: Commercial Fixed Wing
Reporter organization: Government
Reporter function: Approach; Supervisor / CIC
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Workload; Situational Awareness; Training / Qualification; Confusion; Communication Breakdown
Second reporter function: Approach; Supervisor / CIC
Anomaly: ATC Issue All Types; Airspace Violation All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic
Contributing factors: Airspace Structure; Company Policy; Human Factors; Procedure; Staffing
Primary problem: Procedure

Narrative: I was working the CIC (Controller in Charge). There was training being conducted on one of the sectors. O'Hare was landing from east to west on West Plan. For an unknown reason; even though it is desired to fully load the straight in; high and wide fix from the Center first; before offloading aircraft; Center feeder Sector offloaded multiple planes onto the VEECK Arrival. These aircraft; are a direct conflict and hindrance for ORD departures; as well as the MDW Departures. Therefore; it is common practice to discourage excessive use of this arrival route; unless previously coordinated. Apparently; due to the lack of volume on the WATSN Arrival; the MAC (Main Arrival Coordinator) assigned these aircraft to Runway 27L. This runway is normally delivered via the WATSN arrival. The feeder airspace from the southeast; requires the aircraft to fly to 20 miles from ORD; before turning north. This allows departures an opportunity to climb once east of these arrivals; and still have room to climb above the WATSN Arrival inbounds. So typically; any aircraft that end up on the VEECK get sent to the center runway. To accommodate a single base to final turn (versus base; downwind; base; final) the feeder called the LOOP sector to point out several arrivals; turning north early traversing the departure corridor. However; due to volume; and the fact that ORD was currently sending MOBLE Departures out north instead of south; the LOOP Sector was closed. This meant Sector 1 owned this airspace; and climbed the MDW departures on their own; versus handing off to LOOP. So; LOOP was combined with East Departure. But they don't own the LOOP airspace. The east Departure Controller took the point out from the feeder. They never mentioned that LOOP was closed; or that Sector 1 had the airspace. This resulted in two aircraft head on situation with the two aircraft. Sector 1 was overwhelmed due to arrival traffic volume; climbing their departures; and on top of it missing arrivals that they were never coordinated about. The Z Arrival Controller operated under the assumption that whomever was working Aircraft Y was going to miss them; since they thought they had taken the point out. Somehow the two planes ended up separated. However; due to many small issues; the holes of the swiss cheese lined up. A near disaster was imminent. The room was very contentious as everyone attempted to figure out what was going on; and what to do. There were multiple issues with how this was handled. Then to top it off; once it was determined that no loss had occurred; no MOR [Mandatory Occurrence Report] appeared filed. This is unacceptable. This event showed how poor communication has the potential to create terrible consequences. When LOOP sector is closed; since Sector 1 uses that airspace; the position should be forwarded to sector 1; not East Departure. Perhaps refresher training on landline phraseology; should be given to everyone in the facility as well.


Second narrative: [Report narrative contained no additional information.]


Synopsis: TRACON Controllers reported an unusual sector configuration and combination caused the controllers to miss point outs which resulted in a confliction between a departure and an arrival.