Narrative:

During climb phase (around FL280) an ECAM message appeared showing 'hydraulic G rsvr lo lvl'. First officer was pilot flying and I assigned him to continue to fly the aircraft and talk to ATC. It was not an ECAM exception/immediate action so I completed the ECAM actions listed; and then followed up with the QRH/supplemental books. I declared an emergency with ATC. I was then sending an ACARS message to dispatch/maintenance control to advise them of the situation. I also notified the flight attendants and explained the situation. [About ten minutes later] we had an ECAM 'smoke lavatory smoke' warning. I called the 1st flight attendant and told her the situation. She stated that a passenger had entered an aft lavatory and used a 'fake' cigarette (the kind some people use I assume to help stop smoking). The vapor from this cigarette caused the smoke alarm to activate. During the descent; I kept the flight attendants and passengers informed. I told them we had a hydraulic problem and we would be returning to [departure airport]. I also said we would be configuring earlier than normal and that when the landing gear went down there would be more noise/rumbling than normal because the gear doors would still be open. We would land and stop on the runway and wait to be towed to the gate because I had no nose wheel steering. I told the flight attendants to prepare for a precautionary landing. On the downwind leg we started to configure flaps (which moved much slower than normal). On base leg we manually extended the landing gear and were fully configured before final fix. I expected a normal landing and did not use a 'brace' signal. We configured early in case a further problem developed. In that case we would go-around and go to plan B. After landing we came to a full stop. I made an announcement to the passengers; started the APU; and shut down the engines. A few minutes later; maintenance arrived with a tug. They received the gear pins from me; secured the gear; and towed us to a gate. [Maintenance] later told me that the #1 engine hydraulic pump had a failure of some sort with a line resulting in dumping the fluid overboard.

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Original NASA ASRS Text

Title: A319 Captain reported loss of Green hydraulic system; apparently due to failure of a line at the #1 pump. Flight declared emergency and returned to departure airport.

Narrative: During climb phase (around FL280) an ECAM message appeared showing 'HYD G RSVR LO LVL'. First Officer was pilot flying and I assigned him to continue to fly the aircraft and talk to ATC. It was not an ECAM exception/immediate action so I completed the ECAM actions listed; and then followed up with the QRH/Supplemental books. I declared an emergency with ATC. I was then sending an ACARS message to Dispatch/Maintenance Control to advise them of the situation. I also notified the flight attendants and explained the situation. [About ten minutes later] we had an ECAM 'SMOKE LAVATORY SMOKE' warning. I called the 1st Flight Attendant and told her the situation. She stated that a passenger had entered an aft lavatory and used a 'fake' cigarette (the kind some people use I assume to help stop smoking). The vapor from this cigarette caused the smoke alarm to activate. During the descent; I kept the flight attendants and passengers informed. I told them we had a hydraulic problem and we would be returning to [departure airport]. I also said we would be configuring earlier than normal and that when the landing gear went down there would be more noise/rumbling than normal because the gear doors would still be open. We would land and stop on the runway and wait to be towed to the gate because I had no nose wheel steering. I told the flight attendants to prepare for a precautionary landing. On the downwind leg we started to configure flaps (which moved much slower than normal). On base leg we manually extended the landing gear and were fully configured before final fix. I expected a normal landing and did not use a 'BRACE' signal. We configured early in case a further problem developed. In that case we would go-around and go to plan B. After landing we came to a full stop. I made an announcement to the passengers; started the APU; and shut down the engines. A few minutes later; Maintenance arrived with a tug. They received the gear pins from me; secured the gear; and towed us to a gate. [Maintenance] later told me that the #1 engine hydraulic pump had a failure of some sort with a line resulting in dumping the fluid overboard.

Data retrieved from NASA's ASRS site as of July 2013 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.