At this stretch of the river, the bottom is wide (about 80 m), making the river's flow very changeable and creating shoals. Navigation is impeded by shifting sandbars at the confluence of the Warta. The Oder is regulated, but the stream channel is devastated. Past the confluence of the Warta, navigable depths on the Oder range from 100 to 250 cm. The highest water levels usually occur in March and April, while the lowest is in the summer months. The river is navigable for 250, up to 350 days a year. This section meets class III requirements for waterways (navigable depth: 180 cm), which allows navigation of vessels of up to 1000 to 1500 tonnes. Along the border section of the Oder River (km 542.4-704.1) navigation by night is permitted (except for sports and tourist craft). The Water Management Administration in Szczecin and the Water and Shipping Administration in Eberswalde make relevant decisions to that effect and announce them in a form of a communication. No power lines, bridges or ferries impede navigation here. In Gozdowice (at km 645), a self-propelled paddle wheeler ferry 'Bez Granic' runs from April to October. Apart form the port of Kostrzyn (at 617.6 km) at the mouth of the Warta, designated mooring sites are only available in Kaleńsko (at 623.7 km). In Kienitz (at 632 km), there is a marina.