Crj-700 flight crew reported smoke in the cabin prompting a return to departure airport.

Attributes
ACN	1540147
Time
Date	201805
Local Time Of Day	0601-1200
Place
Locale Reference	DTW.Airport
State Reference	MI
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Regional Jet 700 ER/LR (CRJ700)
Operating Under FAR Part	Part 121
Flight Phase	Takeoff
Flight Plan	IFR
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy Deviation - Procedural Weight And Balance Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

On takeoff roll after V1 flight deck received a call from the flight attendants. First officer was flying so captain answered call after autopilot was engaged. Flight attendants stated there was smoke filling cabin from lavatory. Received smoke aft lav warning message while speaking to the flight attendants. The captain gave the flight attendants [instructions]. [Advised] ATC and returned to departure airport. Captain accomplished the QRH procedure while first officer flew. Conducted visual approach with overweight landing (67;500 lbs). Once stopped captain called flight attendants; flight attendants confirmed smoke was no longer building further. Captain elected to perform an expedited deplaning out of the main cabin door on runway due to possible further threat of smoke or fire. All passengers were deplaned and no injuries occurred. Passengers were shuttled back to the terminal and aircraft was towed back to gate.smoke in the aft lavatory entering cabin caused flight attendants to contact flight deck during takeoff; combined with smoke aft lav warning message led to a return to field with an overweight landing followed by an expedited deplaning out of the main cabin door on the runway. No suggestions for crew to avoid recurrence of event. Suggest continued training for flight and cabin crews during recurrent training on emergencies during and after takeoff to help prepare them for such an event.

Original NASA ASRS Text

Title: CRJ-700 flight crew reported smoke in the cabin prompting a return to departure airport.

Narrative: On takeoff roll after V1 flight deck received a call from the Flight Attendants. First Officer was flying so Captain answered call after autopilot was engaged. Flight Attendants stated there was smoke filling cabin from lavatory. Received Smoke Aft Lav warning message while speaking to the Flight Attendants. The Captain gave the Flight Attendants [instructions]. [Advised] ATC and returned to departure airport. Captain accomplished the QRH procedure while First Officer flew. Conducted visual approach with overweight landing (67;500 lbs). Once stopped Captain called Flight Attendants; Flight Attendants confirmed smoke was no longer building further. Captain elected to perform an expedited deplaning out of the main cabin door on runway due to possible further threat of smoke or fire. All passengers were deplaned and no injuries occurred. Passengers were shuttled back to the terminal and aircraft was towed back to gate.Smoke in the aft lavatory entering cabin caused Flight Attendants to contact flight deck during takeoff; combined with SMOKE AFT LAV warning message led to a return to field with an overweight landing followed by an expedited deplaning out of the main cabin door on the runway. No suggestions for crew to avoid recurrence of event. Suggest continued training for flight and cabin crews during recurrent training on emergencies during and after takeoff to help prepare them for such an event.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.