Method of priming a drainage apparatus for siphoning liquid and drainage apparatus

A drainage apparatus for siphoning liquid between first and second reservoirs having respective reservoir floors, the apparatus comprising:

• a conduit arrangement having a first opening disposed in the first reservoir, a second opening disposed in the second reservoir and a liquid injection inlet arranged between the first and second openings for directing liquid into and to fill up most of the conduit arrangement;
• wherein the conduit arrangement further includes a first arm positioned along the first reservoir's floor and in direct fluid communication with the first opening, a second arm positioned along the second reservoir's floor and in direct fluid communication with the second opening, the first and second arms being positioned at a same liquid level;
• and
• at least one valve for controlling flow of the liquid along the conduit arrangement;
• wherein prior to using the drainage apparatus for siphoning the liquid,
• the liquid injection inlet is configured to receive liquid to fill up most of the conduit arrangement as controlled by the valve;
• wherein the first opening is configured to receive more liquid which has been directed into the first reservoir until a continuous liquid flow path is formed which extends from the first opening, the first arm, the second arm and up to at least the second opening, the continuous flow path configured to create a siphon which is at a state of equilibrium to prime the conduit arrangement and the first opening is kept below the liquid's surface level in the first reservoir with the liquid levels in the first arm and the second arm configured to be at the same level;
• and
• wherein the drainage apparatus further comprises an inverted U-shaped portion coupled orthogonally to the first arm, wherein the first opening is disposed at an end of the inverted U-shaped portion in the first reservoir and arranged to face the floor of the first reservoir;
• whereby after priming and in use, the siphon is triggered automatically when more liquid is added into the first reservoir which causes the added liquid to be siphoned to the second reservoir via the primed conduit arrangement.

A drainage apparatus adapted to siphon liquid between first and second reservoirs having respective reservoir floors, the apparatus comprising:

• first and second openings;
• a conduit arrangement configured to be filled with the liquid;
• and
• at least one valve arranged along the conduit arrangement to control flow of the liquid in the conduit arrangement via the first and second openings,
• wherein at least one of the first and second openings is configured to be at least twice a diameter of the conduit arrangement;
• and
• wherein the conduit arrangement includes a first arm positioned along the first reservoir's floor and in direct fluid communication with the first opening, a second arm positioned along the second reservoir's floor and in direct fluid communication with the second opening, wherein the first and second arms are disposed at a same liquid level;
• and
• wherein the drainage apparatus further comprises an inverted U-shaped portion coupled orthogonally to the first arm, wherein the first opening is disposed at an end of the inverted U-shaped portion, in the first reservoir and arranged to face the floor of the first reservoir;
• whereby after priming the conduit arrangement and in use, siphon is triggered automatically when more liquid is added into the first or second reservoir.