The blueprint has two liquid inputs and one output. The high-priority input (H) is drained first up to dry pipes, and the low-priority input (L) is drained only if the consumption at the output exceeds the inflow from the high input. The blueprint is tolerant of differences in input head lifts and must be powered to function properly; it consumes 8MW of power (one Mk2 pump). For some reason, the Variable Priority Junctions described on page 16 of the Satisfactory Plumbing Manual do not work for me in some cases, whereas this blueprint operates smoothly all the time.