Modelling assessment of Bioretention Zones using GIS and SWMM

Abstract

This study assesses the potential implementation of Bioretention Zones (BRZ) in the Bogota campus at the Universidad Nacional Colombia. The goal of the paper is to present a simplified methodology that considers a BRZ scenario for mitigating runoff peaks in the campus. The project methodology is three folded: (1) a suitability analysis for BRZ implementation, (2) configuration and calibration of a rainfall- runoff model, and (3) simulation and assessment of one BRZ scenario in the study area. The GIS-based suitability analysis revealed that at least 10% of the delineated urban catchment may be suitable for BRZ implementation. An 11-BRZ scenario that captures runoff from 11.9% of the catchment area resulted in a subcatchment’s peak-runoff reduction between 10% to 42%. However, the overall peak reduction may not achieve the 30% peak reduction required by Colombian regulations. Besides the potential location of BRZ, the potential subcatchment runoff is suggested as a planning variable to improve the assessment of this SUDS typology for peak-runoff reduction.