Mapping the local impacts of water consumption with regionalized three-dimensional arrays

This study aims to develop a regionalized characterization model of water consumption that can delineate what the potential damage receptors are and where they will be. In order to improve local water resources management, assessment results with more accurate spatial information are needed. This model could be used to derive regionalized life cycle assessment (LCA) results, especially for evaluations within a country.

We developed a regionalized characterization model using a watershed-affected matrix and related factors. To construct the watershed-affected matrix, a watershed-affected area (WAA) describing the geographical boundary that will be affected by insufficient water supply from the watershed was proposed as a spatial scale to evaluate the impacts of local water consumption. The model could be performed with input water consumption inventory data carrying watershed scale attributes, and with output damage results carrying local administrative scale attributes. The area of concern (AoC) concept was applied to the model so that water consumption users, such as domestic, agricultural, and industrial sectors, could be used as damage receptor to reveal societal concern about which sector will be influenced due to water depletion.

This regionalized characterization model was tested on the three main watersheds in Taiwan, each representing typical, but different, water-usage features. Sector-wise WAAs of each watershed were constructed, and endpoint characterization factors (CFs) of local water consumption were calculated. The visualization results show the damage distribution of water consumption among the damage receptors, which used to be a single average value at the watershed or national scale.

The model with the AoC concept is sufficiently flexible for choosing representative affected users and outcome indicators according to stakeholder preferences. Spatial differentiation and comparable results can also support LCA interpretation with detailed information. This model is expected to be further applied to the development of damage prevention strategies.