Narrative:

Climbing thru FL310; EICAS msg 'left hydraulic qty' and 'rsv' light illuminated on overhead panel. Status page showed left hand hydraulic fluid decreasing rapidly. As the pilot flying; I took control of the ATC communications while the first officer went to the FM. Per FM procedure; turned off both engine driven and electric pumps for left hand system. Fluid loss slowed almost immediately. We notified ATC of situation and that we were returning; declaring an emergency and requesting crash fire rescue equipment equipment upon arrival. Notified dispatcher and the purser of the nature of the problem; and that we intended to return. Also made cabin announcement to passengers concerning reason for return and alerting them to crash fire rescue equipment equipment upon arrival. As the first officer ran the checklist for the system failure and reviewed landing distance criteria per fom/FM; I coordinated info with the purser concerning arrival time and possible further actions if we had additional hydraulic system problems during flap and gear extension. We briefed approach and completed all checklists and then began to setup for approach to the longest runway into the wind. On downwind; we began to lower approach flaps; landing gear and final flaps by turning on the left pumps. All extended normally with the remaining fluid in the system. We then shut off all lh pumps. Coordinated with approach and tower for a long straight in final and a desire to roll to the end; explaining we might lose nosewheel steering. Upon rollout; I had normal steering as I slowed to approx 10 kts; so I turned off and headed for the runup pad as briefed. Equipment surrounded aircraft and we shut down the lh engine following cool down; followed by rh engine as soon as we stopped in the pad. Crash fire rescue equipment personnel said they did not see any leaks; smoke or other hazards and I notified purser that I wanted flt attendants to remain at their jumpseats in case we had any reason to evacuate the aircraft. Mechanics and tug arrived within 5-6 minutes and also stated they couldn't see anything hazardous aside from some hydraulic fluid in the lh wheel well area dripping on the ground. We were tugged to the gate and called the duty manager for debriefing. I felt like this was as smooth an emergency situation as could be expected; albeit very time compressed.

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Original NASA ASRS Text

Title: B757 Flight Crew experiences left hydraulic quantity low during climbout and turns of left pumps per checklist procedures. Crew declares an emergency and returns to departure airport where remaining fluid is sufficient to allow normal gear and flap extension and landing.

Narrative: Climbing thru FL310; EICAS Msg 'LEFT HYD QTY' and 'RSV' light illuminated on overhead panel. Status page showed left hand hydraulic fluid decreasing rapidly. As the Pilot Flying; I took control of the ATC communications while the F/O went to the FM. Per FM procedure; turned off both engine driven and electric pumps for left hand system. Fluid loss slowed almost immediately. We notified ATC of situation and that we were returning; declaring an emergency and requesting CFR equipment upon arrival. Notified Dispatcher and the Purser of the nature of the problem; and that we intended to return. Also made cabin announcement to passengers concerning reason for return and alerting them to CFR equipment upon arrival. As the F/O ran the checklist for the system failure and reviewed landing distance criteria per FOM/FM; I coordinated info with the Purser concerning arrival time and possible further actions if we had additional hydraulic system problems during flap and gear extension. We briefed approach and completed all checklists and then began to setup for approach to the longest runway into the wind. On downwind; we began to lower approach flaps; landing gear and final flaps by turning on the left pumps. All extended normally with the remaining fluid in the system. We then shut off all LH pumps. Coordinated with Approach and Tower for a long straight in final and a desire to roll to the end; explaining we might lose nosewheel steering. Upon rollout; I had normal steering as I slowed to approx 10 kts; so I turned off and headed for the runup pad as briefed. Equipment surrounded aircraft and we shut down the LH engine following cool down; followed by RH engine as soon as we stopped in the pad. CFR personnel said they did not see any leaks; smoke or other hazards and I notified Purser that I wanted Flt Attendants to remain at their jumpseats in case we had any reason to evacuate the aircraft. Mechanics and tug arrived within 5-6 minutes and also stated they couldn't see anything hazardous aside from some hydraulic fluid in the LH wheel well area dripping on the ground. We were tugged to the gate and called the Duty Manager for debriefing. I felt like this was as smooth an emergency situation as could be expected; albeit very time compressed.

Data retrieved from NASA's ASRS site as of April 2012 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.