The river Khan is an ephemeral

Ephemeral

Ephemeral things are transitory, existing only briefly. Typically the term is used to describe objects found in nature, although it can describe a wide range of things....

 river crossing the Erongo region of central Namibia

Namibia

Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...

. It is the main tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Swakop River

Swakop River

The Swakop River is a major river in the western part of Namibia, reaching the sea at the southern edge of the city of Swakopmund . The Swakop is an ephemeral river, its run-off is roughly 40 million cubic metres per annum. The main tributary is the Khan...

 and only occasionally carries surface water during the rain season

Wet season

The the wet season, or rainy season, is the time of year, covering one or more months, when most of the average annual rainfall in a region occurs. The term green season is also sometimes used as a euphemism by tourist authorities. Areas with wet seasons are dispersed across portions of the...

s in November and February/March.

The Khan has its origin near the settlement of Otjisemba north-west of Okahandja

Okahandja

Okahandja is a town of 14,000 inhabitants in Otjozondjupa Region, central Namibia, and the district capital of the Okahandja electoral constituency. It is known as the Garden Town of Namibia. It is located 70km north of Windhoek on the B1 road...

. From there the river course passes westwards to the town of Usakos

Usakos

Usakos is a city on the banks of river Khan, 140 kilometres north-east of Swakopmund in the Erongo Region of Namibia. It is located on the B2 , the main road between the Walvis Bay and Johannesburg. The town has 3,000 inhabitants and owns of land...

, and further in south-western direction through the Namib desert. It has its confluence

Confluence

Confluence, in geography, describes the meeting of two or more bodies of water.Confluence may also refer to:* Confluence , a property of term rewriting systems...

 with Swakop River 40km east of Swakopmund

Swakopmund

Swakopmund is a city on the coast of northwestern Namibia, west of Windhoek, Namibia's capital. It is the capital of the Erongo administrative district. As a seaside resort, the weather is cooler here in December to January so the territorial administration moves to Swakopmund for these months...

.