The Lusatian Neisse (German Lausitzer Neiße, Polish Nysa Łużycka, Czech Lužická Nisa) is a river in the Czech Republic (54 km) and on Polish-German border (198 km), in total 252 km long. It flows into Oder River near Gubin.
From the source to the mouth of NysaLuzycka river the catchment is divided into two parts, nearly symmetrically placed along the river course.
The greatest influence on the level of the peak and the largest contribution to the volume of the flood waves on the Odra river are due to two rivers: Nysa Klodzka and Bobr.
The largest contribution to the build up of the first wave was due to: the rivers of Nysa Klodzka, Bystrzyca, Kaczawa and Bobr; where in the second wave: the Nysa Klodzka, Sleza and Kaczawa rivers were the most important.