| Cook River / Weheka | |
| Native Name: | Maori: Weheka |
| Pushpin Map: | New Zealand South Island#New Zealand |
| Pushpin Map Size: | 270px |
| Pushpin Map Caption: | Mouth of Cook River / Weheka |
| Source1: | La Perouse Glacier |
| Source1 Coordinates: | -43.5758°N 170.0389°W |
| Source1 Elevation: | 890m (2,920feet) |
| Mouth: | Tasman Sea |
| Mouth Location: | 2km (01miles) south of Gillespies Beach |
| Mouth Elevation: | 0m (00feet) |
| Mouth Coordinates: | -43.4297°N 169.7892°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | New Zealand |
| Subdivision Type2: | Region |
| Subdivision Name2: | West Coast |
| Subdivision Type3: | District |
| Subdivision Name3: | Westland |
| Length: | 34km (21miles) |
| Progression: | La Perouse Glacier → Cook River / Weheka → Tasman Sea |
| River System: | Cook River / Weheka |
| Tributaries Left: | Driblet Creek, Hermit Creek, Bullock Creek (upper section), Bullock Creek (lower section) |
| Tributaries Right: | McBain Creek, Balfour River, Fox River, Clearwater River |
The Cook River / Weheka is in the South Island of New Zealand. The headwaters are from the La Perouse Glacier on the western flanks of the Southern Alps / Kā Tiritiri o te Moana, and it flows west, then northeast, then northwest and into the Tasman Sea. Its tributaries include the Balfour River, fed by Balfour Glacier, and the Fox River, fed by Fox Glacier / Te Moeka o Tuawe. Much of the river lies within the Westland Tai Poutini National Park.[1] The river was renamed from Cook River to Cook River / Weheka as a result of the Ngāi Tahu Claims Settlement Act 1998.
Brown trout can be fished for in the river.[2]
Access along the river by foot is difficult beyond the junction with the Balfour River. There are no approved helicopter landing sites in the river valley, but there are chamois, tahr and small numbers of red deer available to hunters.[3]