Millennium Green, Garstang

Flow rate (m³/s) measures how much water passes a point per second. Higher flow rates mean stronger currents. Gentle flow (<8 m³/s) is easier for swimming, while strong flow (>15 m³/s) requires experience and caution.

Rain in the catchment area increases river levels and flow rates, sometimes hours or days after the rain fell. Heavy rain can also wash debris into the river and reduce water clarity.

Flow estimates come from a global river discharge model (GloFAS) with a ~5km grid. Smaller rivers and tributaries may not be covered. When flow data is unavailable, use rainfall data as a guide — recent heavy rain likely means higher flows. Always assess conditions carefully before entering.

After heavy rain, rivers can carry branches, logs, and other debris. Higher debris risk means more floating hazards and reduced visibility underwater. Be extra cautious after storms.

Rising levels mean more water is entering than leaving - conditions may get more challenging. Stable levels are predictable. Falling levels mean improving conditions, but be aware of what caused the rise.

Weirs create dangerous recirculating currents that can trap even strong swimmers. Never swim near weirs. Warning distances in the data indicate known weirs - always give them a wide margin.