Design of a Bioretention System with Water Reuse for Urban Agriculture through a Daily Water Balance

The present work proposes the use of green infrastructure (GI) called sustainable urban agriculture drainage systems with water reuse (SUADS-WR) to manage percolated water sustainably in urban agricultural areas (f.i. golf courses). The substrate of the system is commonly used in golf courses and includes a subsurface reservoir for water that exceeds the edaphic zone. Data obtained from a lysimeter, installed in a golf course in Spain, are used to validate the methods employed in developing hydro-informatics tools based on daily water balance, which estimates the water requirement for crops, reservoir height, and capacity for unused water reuse. Reference evapotranspiration can be estimated using the Penman-Monteith or Hargreaves-Samani method. The results were compared with experimental data, revealing that the estimated irrigation depths were lower than the supplied ones and that the estimated percolation was consistent with the measured field drainage. The applicability of the proposed methods for determining the reservoir height and irrigation depth for any type of crop in urban agricultural areas is confirmed. With the implementation of SUADS-WR, the harvested water depth can cover more than 38% of the annual water demand for the crop and utilize leached fertilizers, thus preventing pollution of the receiving surface water body or groundwater.