net 17 of each netting assembly is attached to a lifting structure not shown which may be similar to the lifting basket 18 described in fig1 a above or in the form of lifting frame 18 a described in fig1 b above where the traps 12 a 12 b are submerged door grates 22 c are provided above the traps 12 a 12 b to permit them to be raised for periodic removal of captured debris a bypass weir 23 c may be located above the traps 12 a 12 b to allow flow to divert from the inlet 13 to permit continued flow in the event that traps 12 a 12 b are both filled to capacity with debris in fig2 a and 2 b are illustrated netting assemblies for the traps 12 for use in systems 10 of the various types illustrated in fig1 a 1 c described above according to certain aspects of the invention the netting assemblies 19 are constructed with a mesh net 17 connected to a frame assembly 30 the frame assembly 30 includes a rectangular frame body having a pair of horizontal top and bottom members 31 and 32 respectively and a pair of side members 33 the top member 31 is wider than the bottom member 32 and the side members 33 are tapered from the wider top member toward the narrower bottom member.