Development and application of DRAINMOD model for simulating crop yield and water conservation benefits of drainage water recycling

Drainage water recycling (DWR) is an emerging practice that has the potential to increase crop yield and improve quality. DWR involves capturing storing subsurface drainage surface runoff in ponds or reservoirs, using this for supplemental irrigation during dry periods of growing season. The main objective study was enhance DRAINMOD model simulate hydrology systems. expanded model; named DRAINMOD-DWR, a new module conducts balance storage reservoir simulates interaction between field, irrigated from and/or draining into reservoir. predicts long-term performance as affected by weather conditions, soil type, rotation, size, management. Three metrics were defined based on predictions quantify irrigation, yield, capture benefits DWR. To demonstrate features model, uncalibrated DRAINMOD-DWR applied hypothetical system with continuous corn 50-yr (1970–2019) record Eastern North Carolina, U.S. Different sizes simulated how can predict effect capacity system’s performance. predicted 3.0-m deep area 4% field would optimize conditions. application clearly demonstrated model’s capability optimizing design avoid under-sizing over-sizing reservoir, which reduces increases implementation cost. Research needed test measured data, develop routines simulating fate transport nutrients sediment enable quality