The Gorge River is a river on the West Coast of New Zealand. It arises in the Hope Blue River Range and flows south-west into the Tasman Sea. Its tributaries include the Duncan River and Jerry River. It passes through Cascade Forest. Its mouth is about 15 km north-east of Awarua Point. The Gorge Islands are very small islands near the mouth. At its mouth, it iā¦The Gorge River is a river on the West Coast of New Zealand. It arises in the Hope Blue River Range and flows south-west into the Tasman Sea. Its tributaries include the Duncan River and Jerry River. It passes through Cascade Forest. Its mouth is about 15 km north-east of Awarua Point. The Gorge Islands are very small islands near the mouth. At its mouth, it is a fast tidal river.