Gretna is a city in Jefferson Parish, Louisiana, located on the west bank of the Mississippi River. The climate in Gretna is humid subtropical, with hot and humid summers and mild winters. The city sits at the confluence of the Mississippi River and the Harvey Canal, which provides a vital link between the river and the local industrial complex. The hydrology constituents of the area are largely influenced by the river and its surrounding wetlands, which are home to a diverse range of flora and fauna. Outdoor recreation opportunities include fishing and boating on the river and nearby waterways, hiking and biking in the wetlands, and visiting local parks and green spaces.