Narrative:

Approximately 30 minutes into the flight #1 flight attendant reported there was no potable water from the galley or lavatory sinks. Toilets were operating. A VHF call was made to dispatch. Maintenance services joined the conversation. Maintenance had us check the status of 3 circuit breakers that affect the potable water system. They asked us to check all water valves open and water quantity. All circuit breakers were in; all valves were open and water quantity was about 45 gallons. Maintenance asked us to check if air was coming out of the lavatory facets. We informed tech air appeared to be sucking into the faucets. Maintenance advised us that potable water would probably be unavailable for the flight. The focus was whether to continue or divert. At this point in time no one suspected a possible water leak. I checked with the flight attendants if there was enough bottled water for the passengers and crew; they indicated there would be enough bottled water as a well the normal complement of beverages. The issue was no potable water in the lavatory for people to wash their hands. As a crew we discussed diverting or continuing based on that information. Dispatch and I discussed this was an issue of passenger comfort and not one of safety at this point in time. I informed dispatch and the flight attendant that I would make a PA informing the passengers of the situation. The crew and I discussed flying at a higher mach to shorten the overall time. A while later heard a bang followed by a grinding vibration sound. The aircraft was at FL340 in smooth air; non icing conditions. We quickly noticed the N2 vibration reading on the rh engine was and amber 4.2. All other engine indication appeared normal. There was no EICAS message. We slowly reduced the thrust level on the rh engine per QRH. The vibration level decreased to the normal range at approximately 80 percent N1. However; I reduced the power to 70 percent N1. The vibration/grinding sound stopped as well. ATC was notified; an emergency was declared. We indicated to ATC the condition of the right engine and that we would probably divert where and overweight landing would be made. Airfield fire fighting and rescue would be required as well. We decided the nearest airport would be our diversion airport. The flight attendants were tested and told to secure their galley. The passengers were informed as well that the right engine was operating at a reduced but stable power setting of 70 percent. Dispatch was notified via ACARS. No satcom on aircraft. We then established an HF phone patch with dispatch and maintenance. Communications via HF were difficult. They were both informed of the situation. Maintenance asked about our water quantity. The relief officer went back to the forward galley and reported zero quantity. Maintenance indicated for the first time that a water leak from the potable water access panel we probably the cause. Ice build up as the access panel may be broken and was ice possibly was ingested in the rh engine. The relief officer also checked the right leading edge of wing along with engine cowl with the aid of the wing inspection light. No damaged was observed. Descending through approximately FL200 the ATIS was received for our divert airport. Although the ceiling; visibility; and winds were acceptable; the runway conditions were not. ATIS was giving contaminated runway conditions of ice and snow with fair to poor braking action. The aircraft weight was approximately 232;000 pounds. I checked the QRH misc section as well the performance section of volume 1. Landing section gave required runway landing length. 757 flaps 30 at sea level indicates 8230 ft with poor braking action. The first divert airport was approximately 500 ft elevation and runway 10;000 feet. Without reverse thrust add 4071 feet we were aware that an asymmetrical reverse thrust situation may limit our use of reverse thrust thereby increasing our stopping distance. As well give direction control problems. As a result; at approximately 13;000 ft we informed ATC that this airport was not a suitable alternate. We requested a climb to FL260 and turn to our next diversion choice. I checked engine inoperative altitude on FMC. FL225 was optional alternate with inoperative engine. Dispatch was informed as well. The right engine was still performing well enough in our judgment. Flight attendants and passengers were informed of the new diversion. We landed at 206;000 pounds with good braking action and no cross wind. The airfield fire fighting and rescue personnel were ready to inspect the aircraft per our earlier request. After landing we observed water that froze along the right side of the fuselage at and downstream of the water access panel. The frozen water was rather smooth and uniform to the fuselage. The other point is we should requested the ATIS earlier and questioned ATC on field conditions.

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Original NASA ASRS Text

Title: A B757-200's potable water fill valve was leaking in flight after being serviced in cold weather during preflight. The water froze along the aircraft's fuselage eventually departing and damaging the right engine. An emergency was declared and the flight diverted to an enroute alternate.

Narrative: Approximately 30 minutes into the flight #1 Flight Attendant reported there was no potable water from the galley or lavatory sinks. Toilets were operating. A VHF call was made to Dispatch. Maintenance services joined the conversation. Maintenance had us check the status of 3 circuit breakers that affect the potable water system. They asked us to check all water valves open and water quantity. All circuit breakers were in; all valves were open and water quantity was about 45 gallons. Maintenance asked us to check if air was coming out of the lavatory facets. We informed tech air appeared to be sucking into the faucets. Maintenance advised us that potable water would probably be unavailable for the flight. The focus was whether to continue or divert. At this point in time no one suspected a possible water leak. I checked with the flight attendants if there was enough bottled water for the passengers and crew; they indicated there would be enough bottled water as a well the normal complement of beverages. The issue was no potable water in the lavatory for people to wash their hands. As a crew we discussed diverting or continuing based on that information. Dispatch and I discussed this was an issue of passenger comfort and not one of safety at this point in time. I informed Dispatch and the Flight Attendant that I would make a PA informing the passengers of the situation. The crew and I discussed flying at a higher MACH to shorten the overall time. A while later heard a bang followed by a grinding vibration sound. The aircraft was at FL340 in smooth air; non icing conditions. We quickly noticed the N2 vibration reading on the RH engine was and amber 4.2. All other engine indication appeared normal. There was no EICAS message. We slowly reduced the thrust level on the RH engine per QRH. The vibration level decreased to the normal range at approximately 80 percent N1. However; I reduced the power to 70 percent N1. The vibration/grinding sound stopped as well. ATC was notified; an emergency was declared. We indicated to ATC the condition of the right engine and that we would probably divert where and overweight landing would be made. Airfield Fire Fighting and Rescue would be required as well. We decided the nearest airport would be our diversion airport. The flight attendants were tested and told to secure their galley. The passengers were informed as well that the right engine was operating at a reduced but stable power setting of 70 percent. Dispatch was notified via ACARS. No SATCOM on aircraft. We then established an HF phone patch with Dispatch and Maintenance. Communications via HF were difficult. They were both informed of the situation. Maintenance asked about our water quantity. The Relief Officer went back to the forward galley and reported zero quantity. Maintenance indicated for the first time that a water leak from the potable water access panel we probably the cause. Ice build up as the access panel may be broken and was ice possibly was ingested in the RH engine. The Relief Officer also checked the right leading edge of wing along with engine cowl with the aid of the wing inspection light. No damaged was observed. Descending through approximately FL200 the ATIS was received for our divert airport. Although the ceiling; visibility; and winds were acceptable; the runway conditions were not. ATIS was giving contaminated runway conditions of ice and snow with fair to poor braking action. The aircraft weight was approximately 232;000 LBS. I checked the QRH misc section as well the performance section of volume 1. Landing section gave Required Runway Landing Length. 757 Flaps 30 at Sea Level indicates 8230 FT with poor braking action. The first divert airport was approximately 500 FT elevation and runway 10;000 feet. Without reverse thrust add 4071 feet we were aware that an asymmetrical reverse thrust situation may limit our use of reverse thrust thereby increasing our stopping distance. As well give direction control problems. As a result; at approximately 13;000 FT we informed ATC that this airport was not a suitable alternate. We requested a climb to FL260 and turn to our next diversion choice. I checked ENG INOP ALT on FMC. FL225 was optional alternate with inoperative engine. Dispatch was informed as well. The right engine was still performing well enough in our judgment. Flight attendants and passengers were informed of the new diversion. We landed at 206;000 LBS with good braking action and no cross wind. The Airfield Fire Fighting and Rescue personnel were ready to inspect the aircraft per our earlier request. After landing we observed water that froze along the right side of the fuselage at and downstream of the water access panel. The frozen water was rather smooth and uniform to the fuselage. The other point is we should requested the ATIS earlier and questioned ATC on field conditions.

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.