Intermittent Spring

Ebb and Flow Springs - Rhythmic Karst Springs - Potajnice

ebb and flow spring, ebbing and flowing well, tidewell. A spring or flowing well exhibiting periodic variation in volume of flow; the periodicity, which is often irregular, is attributed to siphonic action.
Watson Hiner Monroe (1970): A Glossary of Karst Terminology, Geological Survey Water-supply Paper 1899-k, Library of Congress catalog-card No. 75-607530 DOI online