The point of the invention is to evenly distribute water or effluent over an irrigation area or a drain field. Typically the fluid comes from a reservoir or a septic tank and is fed, by gravity, into a number of discharge pipes that would be located underground.The device related to this invention is characterized by a container with an inlet at the top and a number of outlets at the bottom. Inside the container the fluid is directed to the center of a flow splitter surface underneath, via a specifically configured spout. To make the fluid spread radian and uniformly towards the surface's perimeter this surface has hydrophilic properties and is convex shaped. The fluid eventually flows uniformly over the surface's edge and is evenly distributed over the outlets at the bottom.