Methodology for Selecting Best Management Practices Integrating Multiple Stakeholders and Criteria. Part 2: Case Study

The selection of stormwater Best Management Practices (BMPs) for mitigating the effects of urbanization on the hydrological cycle could be a complex process due to conflicting stakeholder views, and varying levels of performance of BMPs across a range of criteria (runoff reduction, erosion control, etc.). Part 1 of this article proposed a methodology based on the application of multi-criteria decision aid (MCDA) methods, which was tested here on a residential stormwater network in the Montreal area. The case study considered green roofs, rain gardens, rain barrels and pervious pavement over a range of economic, social, and water quality and quantity criteria by applying 4 MCDA methods under three different stakeholder views. The results indicated Elimination et Choix Traduisant la Réalité (ELECTRE) III to be the most appropriate method for the methodology, presenting flexibility concerning threshold values, criteria weights, and showing shared top choices across stakeholders (rain gardens, and rain gardens in combination with pervious pavement). The methodology shows potential for more formal applications and research opportunities. Future work may lie in the inclusion of multiple objective optimization, better stakeholder engagement, estimation of economic benefits, water quality modeling, long-term hydrological simulations, and estimating real BMP pollutant removal rates.