A method for operating an on-board water supply and distribution system of an aircraft for supplying water, the system comprising a central water tank, first consumer assemblies, each first consumer assembly comprising a supply device and a buffer tank and each first consumer assembly being configured to supply water from the buffer tank via the supply device, wherein each of the buffer tanks of the first consumer assemblies comprises a heater configured to heat up water in the buffer tank to a disinfection temperature, a pump having an upstream side and a downstream side and being configured such that it may operate in a supply mode and a reverse mode, and a high pressure conduit system, wherein the central water tank is connected to the upstream side of the pump, wherein the high pressure conduit system connects the downstream side with the plurality of first consumer assemblies, with the conduit system being configured such that the pump, when operating in the supply mode, is capable of supplying water from the downstream side to the buffer tank of each of the first consumer assemblies, wherein, when the pump is operating in the reverse mode, it is capable of drawing water from the high pressure conduit system towards the upstream side, the method comprising the following steps: operating the pump in the supply mode so that water from the central tank is supplied to at least one of the first consumer assemblies wherein the buffer tank of the at least one of the first consumer assemblies is filled, operating the heater of the buffer tank of the at least one of the first consumer assemblies in such a manner, that the water in the buffer tank of the at least one of the first consumer assemblies is heated up to a predetermined disinfection temperature, and operating the pump in the reverse mode so that the heated water in the buffer tank of the at least one of the first consumer assemblies passes through a part of the high pressure conduit system and the upstream side of the pump. a central water tank, first consumer assemblies, each first consumer assembly comprising a supply device and a buffer tank and each first consumer assembly being configured to supply water from the buffer tank via the supply device, wherein each of the buffer tanks of the first consumer assemblies comprises a heater configured to heat up water in the buffer tank to a disinfection temperature, a pump having an upstream side and a downstream side and being configured such that it may operate in a supply mode and a reverse mode, and a high pressure conduit system, wherein the central water tank is connected to the upstream side of the pump, wherein the high pressure conduit system connects the downstream side with the plurality of first consumer assemblies, with the conduit system being configured such that the pump, when operating in the supply mode, is capable of supplying water from the downstream side to the buffer tank of each of the first consumer assemblies, wherein, when the pump is operating in the reverse mode, it is capable of drawing water from the high pressure conduit system towards the upstream side, the method comprising the following steps: operating the pump in the supply mode so that water from the central tank is supplied to at least one of the first consumer assemblies wherein the buffer tank of the at least one of the first consumer assemblies is filled, operating the heater of the buffer tank of the at least one of the first consumer assemblies in such a manner, that the water in the buffer tank of the at least one of the first consumer assemblies is heated up to a predetermined disinfection temperature, and operating the pump in the reverse mode so that the heated water in the buffer tank of the at least one of the first consumer assemblies passes through a part of the high pressure conduit system and the upstream side of the pump. operating the pump in the supply mode so that water from the central tank is supplied to at least one of the first consumer assemblies wherein the buffer tank of the at least one of the first consumer assemblies is filled, operating the heater of the buffer tank of the at least one of the first consumer assemblies in such a manner, that the water in the buffer tank of the at least one of the first consumer assemblies is heated up to a predetermined disinfection temperature, and operating the pump in the reverse mode so that the heated water in the buffer tank of the at least one of the first consumer assemblies passes through a part of the high pressure conduit system and the upstream side of the pump.