One should never connect the drip line to the main line. The drip line
should be connected to a sub-main line and the water flow to this
sub-main line can be controlled by fixing a control ball valve. In
existing circumstances you may use pressure compensating emitters which
emit a calibrated amount of water irrespective of the water pressure in
the main water line or land having un-even contour. For more
information you may write to
Girish