The FHI evaluates basin health across three separate components: Ecosystem Vitality, Ecosystem Services and Governance & Stakeholders. For a given basin, a unique value for each of the three components is calculated (on a 0-100 scale). By presenting indices for each of the three components separately, it is easier to see which components are functioning better toward freshwater sustainability and which need further attention to increase overall sustainability. High values across all three of the indices indicate a more sustainable, healthy freshwater ecosystem than indices at the lower end of the scale.
The scores give a baseline evaluation of freshwater health and can users can also evaluate future scenarios, including land-use change, infrastructure development and climate change.