Similitude and dimensional analysis were employed to investigate any underlying scaling law of dissolved oxygen (DO) in coastal streams across the Atlantic Coast of USA. Two mechanistically meaningful dimensionless groups were formulated as the stream ‘metabolic number’ and the ‘DO saturation number’. A scatter-plot between the two groups indicated an emergent process diagram, which represented critical dimensionless thresholds to separate high, transitional, and low metabolism regimes. The ‘DO saturation number’ demonstrated a generalized power law scaling with the ‘metabolic number’ having a robust exponent of 1/3 (Nash-Sutcliffe Efficiency = 0.83-0.85). Our findings provided new insights and tool, which would help restore and manage stream water quality and ecosystem health around the world.
