A new irradiator design for large-scale dual-beam wastewater treatment in jet mode is proposed and analyzed. A combination of technical solutions previously used separately in the design of the ELV-12 and Electron-10 accelerators is considered. Accelerating tubes are used to produce bifurcated beams. Each half-beam is bent by 90° and directed towards the half-beam produced from the adjacent accelerating tube. The water jet is irradiated from both sides in the gap between the beam windows at a speed above 1 m s−1. The electron beams are oriented at an angle of 45–60° to the direction of the water jet. The angle causes a decrease in the useful thickness of the jet, but an increase in the depth dose in the cross section of the jet. Options for simultaneous irradiation of two and four water jets are considered.