A framework for applying interceptive mitigations for diffuse agricultural pollution

Evaluating the Cost-Effectiveness of Green Infrastructure for Mitigating Diffuse Agricultural Contaminant Losses

“…For modeling the interception potential of these mitigations, we extend the framework proposed by Tanner et al [7]. This extension involves incorporating quantitative estimates of the proportion of N, P, and sediment transported by each hydrological flow path, thereby enhancing the precision of our cost-effectiveness estimates for a particular landscape.…”

“…Our model builds on the framework outlined by USEPA [16] and adapted by Tanner et al [7], based on four different archetypal hydrologic landscape types. The four types (Figure 1) are based on different combinations of permeable or impermeable soil and subsoil.…”

“…The contaminants assessed are total nitrogen (TN), total phosphorus (TP), and total suspended sediment (TSS). Although not explicitly quantified here, these systems may also remove other contaminants (e.g., fecal microbes and pesticides) and offer additional environmental benefits, such as biodiversity enhancement, enhanced landscape esthetics, flood risk management, and net reduction in greenhouse gas emissions (Tanner et al [7]). Our focus in the current assessment is on grazed pastoral agriculture, which is the predominant land use in New Zealand, but this approach is equally adaptable to other types of agricultural land use and other regions of the world.…”

“…For example, Weeber et al [12] assessed the feasibility and cost-effectiveness of implementing CW, WB, and aluminized zeolite filters in the Waituna catchment. Tanner et al [7] provided a semi-quantitative framework for selecting interceptive mitigation systems for different hydrological landscape types. They highlighted the relative benefits of each individual mitigation system type in terms of landscape fit, flow-path(s) intercepted, contaminant(s) targeted, efficacy, associated co-benefits, relative cost, operation and maintenance requirements, longevity, and consent requirements.…”

“…This study builds on the Tanner et al [7] framework to include quantitative dimensions of costs and performance, utilizing a mix of case study data and lifecycle costing models. It is noteworthy that, to date, no study has conducted a direct comparison of the cost-effectiveness across such a broad spectrum of interceptive mitigation systems for a particular catchment.…”