Vistula Lagoon of the Ests". Over three hundred years later, in the first half of the 13th Century, the name of Vistula Lagoon occurs in deeds issued by Teutonic Order in Latin version as Mare Recens (1246 - "mare" - a pool or lake or sea and "recens" - fresh) in contrast to the contemporary name for the Baltic Sea - Mare Salsum (Salty Sea). Then in 1251 we find record about Mare Recens et Neriam (Frisches Haff and Frische Nehrung, now Vistula Spit) and finally in 1288 Recenti Mari Hab (Haff) which as one can see corresponds with later German "Frisches
Lagoon coastal transgression and sea level rise. During high flow events there is also the possibility for secondary breaches of the barrier or lagoon truncation to occur. Storm events also have the ability to close hapua outlets as waves overtop the barrier depositing sediment and choking the scoured channel. The resultant swift increase in lagoon water level causes a new outlet to be breached rapidly due to the large hydraulic head that forms between the lagoon and sea water levels. Storm breaching is believed to be an important but unpredictable control on the duration of closures at low to moderate river