Okanagan Lake is called a fjord lake as it has been carved out by repeated glaciations. Although the lake contains numerous lacustrine terraces, it is not uncommon for the lake to be 100 m deep only 10 m offshore. Major inflows include Mission, Vernon, Trout, Penticton, Equesis, Kelowna, Peachland and Powers Creeks. The lake is drained by the Okanagan River, which exits the lake's south end via a canal through the city of Penticton to Skaha Lake, whence the river continues southwards into the rest of the South Okanagan and through Okanogan County, Washington to its confluence with the Columbia. The lake's maximum depth is near Grant Island. There is one other island known as Rattlesnake Island, much farther south by Squally Point. Some areas of the lake have up to of glacial and post-glacial sediment fill which were deposited during the Pleistocene Epoch. Notable features of the Okanagan Valley include terraces which were formed due to the periodic lowering of the lake's predecessor, glacial Lake Penticton. These terraces are now used extensively for agriculture such as fruit cultivation.
During the early days of settlement and development of the Okanagan region, the lack of roads in the region made the lake a natural corridor for passenger travel and freight. The Canadian Pacific Railway Lake and River Service was the main carrier on the lakes, providing freight and passenger connections between Penticton, on the Kettle Valley Railway and Okanagan Landing for connections to the CPR Mainline at Sicamous via the Shuswap and Okanagan Railway. Smaller vessels such as the SS Naramata provided passenger service to smaller settlements around the lake, as well as excursions for tourists.
Vessels
SS Naramata
- 1950-1960
Canadian National Tug no. 6
Canadian National Tug no. 5
MV Kelowna-Westbank
Colleen
Ruth Shorts
Landings
Penticton
Naramata
Peachland
Summerland
Okanagan Mission
Kelowna
Okanagan Landing
Fintry
Carr's Landing
Ewing
Killiney Beach
Recreation
Many parks and beaches are found along the shores of the lake, which make boating and swimming very popular activities. The lake is home to several species of fish, including rainbow trout and kokanee. It is said by some to be home to its own lake monster – a giant serpent-like creature named Ogopogo.