AnglerOS

Glossary

Hydrograph

A hydrograph is a graph of stage or discharge over time—how fast water rose or fell through a storm or drawdown. It turns a single elevation reading into trend context.

Published May 16, 2026 · Editorial standards

Why it matters

A lake “down three feet” means little without knowing whether it is still falling after a two-week drawdown or rebounding after rain. Hydrographs show slope and timing—the shape operators watch when managing flood pool storage.

Where you see them

Lake Insights level charts are hydrographs of stage. NWPS and USGS products use the same idea for rivers. Compare location before comparing shape.

Related terms: Stage · Drawdown · Gauge · NWPS · NOAA

Reference information only. See data sources, editorial standards, or suggest a correction.

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