Vertically 0.5-1 cun.
Caution: be careful with Peritoneum. Take great care during pregnancy.
The name 'Water Separation' clearly indicates its functions of separating clear Water from the turbid. This happens in the Small Intestine and the separated Water get distributed to the Bladder and Large Intestine, respectively.
In fact, Shuifen REN-9 is one of the most important points for treating any sorts of Water pathology, regardless being Dampness, Phlegm or Oedema. It is because it stimulates Body Fluids transportation, transformation and excretion in all body parts.