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Water exiting the manifold does so with a strong horizontal velocity component. This horizontal velocity can, if unchecked, create horizontal flow patterns that amplify imbalanced flow distribution in the manifold discharge and can create circular or horizontal flow patterns in the sediment tank, reducing its effectiveness. This effect can also create undesireable local flow velocities in the vicinity of the manifold that exceed the anticipated design velocities calculated from normal orifice flow alone.
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Further experiments will seek again to clarify the magnitude of the differential flow and test various "corrective" designs to see if more uniform flow will result. Dye tests using he the model will be the primary method of testing in the next phase, although other tests may also be proposed.