REFERENTIEL 3.1 Diffusion de listes de référence par le Sandre 2026-05-03 1987-03-20 2026-05-03 1470 Service d'Administration Nationale des Données et Référentiels sur l'Eau 770 Niveau de l'eau 3 Validé 2013-11-19 2025-08-26T14:41:00 1 equinoctialSpringLowWater equinoctialSpringLowWater Gelé The level of low water springs near the time of an equinox 2013-11-19 2014-10-01T23:00:00 2 higherHighWater higherHighWater Gelé The highest of the high waters (or single high water) of any specified tidal day due to the declination A1 effects of the moon and sun 2013-11-19 2014-10-01T23:00:00 3 higherHighWaterLargeTide higherHighWaterLargeTide Gelé The average of the highest high waters, one from each of 19 years of observations 2013-11-19 2014-10-01T23:00:00 4 highestAstronomicalTide highestAstronomicalTide Validé The highest tidal level, which can be predicted to occur under average meteorological conditions and under any combination of astronomical conditions 2013-11-19 2025-08-21T22:00:00 5 plus hautes eaux plus hautes eaux Validé The highest water level observed at a location 2013-11-19 2014-10-01T23:00:00 6 highWater highWater Gelé The highest level reached at a location by the water surface in one tidal cycle 2013-11-19 2014-10-01T23:00:00 7 highWaterSprings highWaterSprings Gelé An arbitrary level, approximating that of mean high water springs 2013-11-19 2014-10-01T23:00:00 8 indianSpringHighWater indianSpringHighWater Gelé A tidal surface datum approximating the level of the mean of the higher high water at spring tides 2013-11-19 2014-10-01T23:00:00 9 indianSpringLowWater indianSpringLowWater Gelé A tidal surface datum approximating the level of the mean of the lower low water at spring tides 2013-11-19 2014-10-01T23:00:00 10 localDatum localDatum Gelé An arbitrary datum defined by an authority of a local harbour, from which levels and tidal heights are measured by that authority 2013-11-19 2014-10-01T23:00:00 11 lowerLowWater lowerLowWater Gelé The lowest of the low waters (or single low water) of any specified tidal day due to the declination A1 effects of the moon and sun 2013-11-19 2014-10-01T23:00:00 12 lowerLowWaterLargeTide lowerLowWaterLargeTide Gelé The average of the lowest low waters, one from each of 19 years of observations 2013-11-19 2014-10-01T23:00:00 13 lowestAstronomicalTide lowestAstronomicalTide Gelé The lowest tide level that can be predicted to occur under average meteorological conditions and under any combination of astronomical conditions 2013-11-19 2014-10-01T23:00:00 14 plusbasseseaux plus basses eaux Validé An arbitrary level conforming to the lowest tide observed at a location, or somewhat lower 2013-11-19 2014-10-05T23:00:00 15 lowestLowWaterSprings lowestLowWaterSprings Gelé An arbitrary level conforming to the lowest water level observed at a location at spring tides during a period shorter than 19 years 2013-11-19 2014-10-01T23:00:00 16 lowWater lowWater Gelé An approximation of mean low water adopted as the reference level for a limited region, irrespective of better determinations later 2013-11-19 2014-10-01T23:00:00 17 lowWaterDatum lowWaterDatum Gelé An approximation of mean low water that has been adopted as a standard reference for a limited area 2013-11-19 2014-10-01T23:00:00 18 lowWaterSprings lowWaterSprings Gelé A level approximating that of mean low water springs 2013-11-19 2014-10-01T23:00:00 19 meanHigherHighWater meanHigherHighWater Gelé The average height of higher high waters at a location over a 19-year period 2013-11-19 2014-10-01T23:00:00 20 meanHigherHighWaterSpring meanHigherHighWaterSprings Gelé The average height of higher high water at spring tides at a location 2013-11-19 2014-10-01T23:00:00 21 meanHigherLowWater meanHigherLowWater Gelé The average of the higher low water height of each tidal day observed over a National Tidal Datum Epoch 2013-11-19 2014-10-01T23:00:00 22 meanHighWater meanHighWater Gelé The average height of all high waters at a location over a 19-year period 2013-11-19 2014-10-01T23:00:00 23 meanHighWaterNeaps meanHighWaterNeaps Gelé The average height of the high waters of the neap tide 2013-11-19 2014-10-01T23:00:00 24 meanHighWaterSprings meanHighWaterSprings Gelé The average height of the high waters of spring tides 2013-11-19 2014-10-01T23:00:00 25 meanLowerHighWater meanLowerHighWater Gelé The average of the lower high water height of each tidal day observed over a National Tidal Datum Epoch 2013-11-19 2014-10-01T23:00:00 26 meanLowerLowWater meanLowerLowWater Gelé The average height of the lower low waters at a location over a 19-year period 2013-11-19 2014-10-01T23:00:00 27 meanLowerLowWaterSprings meanLowerLowWaterSprings Gelé The average height of lower low water at spring tides at a location 2013-11-19 2014-10-01T23:00:00 28 meanLowWater meanLowWater Gelé The average height of all low waters at a location over a 19-year period 2013-11-19 2014-10-01T23:00:00 29 meanLowWaterNeaps meanLowWaterNeaps Gelé The average height of the low waters of the neap tide 2013-11-19 2014-10-01T23:00:00 30 meanLowWaterSprings meanLowWaterSprings Gelé The average height of the low waters of spring tides 2013-11-19 2014-10-01T23:00:00 31 meanSeaLevel meanSeaLevel Gelé The average height of the sea at a tide station measured from a fixed predetermined reference level 2013-11-19 2014-10-01T23:00:00 32 meanTideLevel meanTideLevel Gelé The arithmetic mean of mean high water and mean low water 2013-11-19 2014-10-01T23:00:00 33 meanWaterLevel meanWaterLevel Gelé The average of all hourly water levels over the available period of record 2013-11-19 2014-10-01T23:00:00 34 nearlyHighestHighWater nearlyHighestHighWater Gelé An arbitrary level approximating the highest water level observed at a location, usually equivalent to the high water springs 2013-11-19 2014-10-01T23:00:00 35 nearlyLowestLowWater nearlyLowestLowWater Gelé A level approximating the lowest water level observed at a location, usually equivalent to Indian spring low water 2013-11-19 2014-10-01T23:00:00 36 tropicHigherHighWater tropicHigherHighWater Gelé The highest of the high waters (or single high water) of the tides occurring semimonthly when the effect of the Moon's maximum declination is greatest 2013-11-19 2014-10-01T23:00:00 37 tropicLowerLowWater tropicLowerLowWater Gelé The lowest of the low waters (or single low water) of the tides occurring semimonthly when the effect of the Moon's maximum declination is greatest 2013-11-19 2014-10-01T23:00:00