Whataroa River facts for kids

Quick facts for kids Whataroa River
Whataroa River flowing out to the Tasman Sea
District	Westland District
Region	West Coast Region
Country	New Zealand
Physical characteristics
Main source	Below Hochstetter Dome Southern Alps
River mouth	Tasman Sea South of Abut Head 0 m (0 ft) 43°07′S 170°15′E / 43.117°S 170.250°E / -43.117; 170.250
Basin features
Tributaries	Left: Butler River, Perth River Right: Gunn River, Barrowman Stream
Bridges	State Highway 6 Bridge

Whataroa River - Upper Reaches. Above the Butler River Junction.

Whataroa River flowing into the Tasman Sea

The Whataroa River (sometimes spelled Wataroa River) is a fast-flowing, scenic river in the West Coast region of New Zealand's South Island. It begins high in the snowy peaks of the Southern Alps and rushes down to the Tasman Sea. Along its journey, it cuts through deep rock canyons, crosses wide gravel flats, and flows past dense native rainforests.

The river is famous for its bright turquoise-blue glacial water, thrilling outdoor adventures like whitewater rafting, and rich natural history. It is also an important part of Māori heritage and local wildlife habitats.

Geography and Course of the Whataroa River

Where Does the River Begin?

The Whataroa River starts high up in the Southern Alps, near a mountain peak called Hochstetter Dome. The source is fed by melting snow and giant glaciers that grind against the mountain rock.

Because it comes from glaciers, the river carries fine particles of crushed rock called "rock flour" or glacial silt. When sunlight hits these tiny suspended particles in the water, it scatters the light and gives the river an incredible bright turquoise or milky-blue colour.

Journey Down the Mountain Valleys

From its alpine birthplace, the river flows north and northwest through remote wilderness. It races through narrow gorges where strong currents carve steep walls out of solid rock.

As it moves lower, the valley begins to widen out into a classic braided river system. In this section, the river splits into many smaller channels that criss-cross over wide gravel and pebble riverbeds.

Tributaries Joining the Flow

Several wild mountain rivers and streams join the Whataroa River along its path:

• Perth River: A major glacier-fed river that joins the Whataroa in a rugged, deep canyon.
• Butler River: A swift mountain tributary that flows from alpine valleys into the upper reaches of the Whataroa.
• Gunn River: Another important tributary that adds cold freshwater from the surrounding mountain ranges.
• Barrowman Stream: A smaller waterway carrying runoff from native bush and alpine hills.

These tributaries significantly increase the volume and power of the Whataroa River, especially during spring thaws and heavy rainfall.

Reaching the Tasman Sea

After leaving the rugged mountain valleys, the Whataroa River flows past the eastern side of the small farming town of Whataroa.

It then passes beneath a major bridge carrying State Highway 6 between Whataroa and the small settlement of Te Taho. Finally, the river empties into the Tasman Sea just south of a coastal headland named Abut Head.

Geology and Landscape Features

Alpine Fault and Mountain Building

The Whataroa River valley is shaped by powerful geological forces. New Zealand sits right across the boundary between two huge tectonic plates: the Pacific Plate and the Indo-Australian Plate.

The famous Alpine Fault runs directly through the West Coast region. Over millions of years, the collision of these tectonic plates has pushed up the Southern Alps at a rate of several millimetres each year.

Glacial Carving and Erosion

During past ice ages, massive glaciers carved deep, U-shaped valleys through the mountains. When the climate warmed and the ice retreated, it left behind steep cliffs, gravel deposits, and giant boulders.

The Whataroa River continues this carving process today through erosion. Heavy rains and rapid water flow grind away rock and carry huge amounts of gravel toward the ocean.

Braided River Systems Explained

A braided river is a river network that consists of multiple small channels separated by temporary islands called gravel bars.

• Braided rivers form when a river carries more sediment (gravel, sand, and silt) than it can easily wash away.
• The slope of the land is steep enough to give the water high energy.
• The riverbanks are made of loose gravel rather than solid rock, allowing channels to shift constantly.

The lower Whataroa River is a classic example of this dynamic landscape. The channels can change position completely after just one large rainstorm.

Climate and Water Flow

High Rainfall of the West Coast

The West Coast is one of the wettest regions in New Zealand and the world. Moisture-laden winds blow eastward across the Tasman Sea and hit the high barrier of the Southern Alps.

As the air rises over the mountains, it cools and drops its moisture as rain or snow. This process is known as orographic precipitation. The upper catchment of the Whataroa River can receive over 5,000 millimetres (200 inches) of rain each year.

River Levels and Flood Risks

Because of the steep mountains and high rainfall, the Whataroa River can rise extremely fast. A calm, crystal-clear river can turn into a roaring brown torrent within a few hours during a heavy storm.

These rapid floods, known as "freshes," sweep away gravel bars, rearrange river channels, and carry fallen trees down to the sea. Outdoor explorers must always check weather forecasts carefully before heading into the river valleys.

Ecosystems and Wildlife

Native Forest Habitats

The Whataroa River valley is home to lush, temperate rainforests. These forests thrive in the high rainfall and mild coastal temperatures.

Major plant species in the area include:

• Rimu (Red Pine): Tall native conifer trees that dominate the forest canopy.
• Kahikatea (White Pine): New Zealand's tallest native tree, often growing in swampy valley floors.
• Southern Rata: Famous for its bright crimson-red flowers that bloom in mid-summer.
• Tree Ferns (Ponga): Large ferns that form the lush green understory of the forest.
• Mosses and Lichens: Thick carpets of green and golden moss covering forest rocks and fallen logs.

Native Birds and Forest Animals

The forests and riverbanks provide critical habitats for many of New Zealand's unique and endangered bird species:

• Kea: The world's only alpine parrot, known for its intelligence, curiosity, and playful behaviour in the high mountain valleys.
• Kākā: A large forest parrot closely related to the kea, known for its harsh calls and acrobatic flying.
• Tūī and Bellbird: Honeyeater birds that feed on nectar and fill the forest with complex, musical songs.
• Pīwakawaka (Fantail): A small, friendly insect-eating bird that darts around hikers to catch disturbed bugs.
• South Island Kōkako: A rare native wattlebird traditionally linked to deep South Island forest valleys.
• Rowi (Okarito Brown Kiwi): A very rare species of kiwi that lives in forests near the coastal regions around Whataroa.

Aquatic Life and Fish Species

The Whataroa River supports a variety of freshwater fish that are adapted to cold, fast-moving mountain water:

• Longfin Eel (Tuna): A remarkable native fish that can live for over 80 years and grow over a metre long.
• Inanga and Koaro: Small native fish whose young form part of the famous New Zealand "whitebait" runs in spring.
• Torrentfish: Highly adapted fish with flattened heads and strong fins that allow them to live in the fastest river rapids.
• Introduced Trout: Brown trout and rainbow trout were introduced to New Zealand in the 19th century and live in several deeper pools and tributaries.

Cultural and Human History

Māori Heritage and Pounamu

For centuries before European settlers arrived, Māori people lived in and travelled through the West Coast, which is known in the Māori language as Te Tai Poutini.

The local Māori people, the Ngāi Tahu iwi (tribe) and Poutini Ngāi Tahu hapū (sub-tribe), value the Whataroa River for its rich natural resources:

• Mahinga Kai: Traditional food-gathering places where people harvested eels, birds, and forest plants.
• Pounamu (Greenstone or New Zealand Jade): A tough, beautiful green mineral found in West Coast riverbeds. Pounamu was highly prized for making durable tools, sharp weapons, and precious ornaments.
• Travel Routes: River valleys served as natural highways through the steep mountains, connecting coastal settlements with high alpine passes leading to the east coast.

The name Whataroa comes from the Māori language, often translated as "long storehouse" or "elevated food stage" (from whata meaning an elevated food storage platform, and roa meaning long or tall).

European Settlement and Gold Mining

In the 1860s, gold was discovered on the West Coast, sparking the West Coast Gold Rush. Thousands of prospectors rushed to the region to search for alluvial gold in river gravels and ocean beaches.

While the largest gold rushes occurred near towns like Hokitika and Ross, prospectors also explored the Whataroa River and its tributaries. Later, European settlers cleared parts of the lower floodplain for dairy farming and sheep grazing.

Bridges and Transport Links

For many decades, crossing the wide and unpredictable West Coast rivers was difficult and dangerous. Early travellers had to wade through river channels on foot or horseback, or use small rowboats and ferries.

The construction of road bridges in the 20th century transformed travel. The bridge over the Whataroa River on State Highway 6 created a reliable link connecting the towns of the West Coast from Greymouth down to Haast.

Outdoor Recreation and Adventure

Whitewater Kayaking and Rafting

The Whataroa River is famous internationally among experienced whitewater kayakers and rafters. Its steep mountain gorges produce powerful, world-class rapids rated between Class IV and Class V on the international river scale.

Key adventure highlights include:

• Helicopter Access: Because the upper gorges are surrounded by steep cliffs and dense bush, rafting teams often fly in by helicopter to reach the launch sites.
• Gorge Scenery: Rafters float through deep granite canyons with waterfalls tumbling hundreds of metres down sheer rock walls.
• Multi-Day Trips: Some expeditions combine the Whataroa with the nearby Perth River for multi-day wilderness adventures.

Tramping and Hiking

"Tramping" is the New Zealand word for wilderness hiking or backpacking. The valleys surrounding the Whataroa River offer challenging routes for experienced trampers.

• Backcountry Huts: The New Zealand Department of Conservation (DOC) maintains simple wooden huts in the valleys where trampers can sleep overnight.
• Rough Trails: Tramping tracks here often follow river banks, cross boulder fields, and require navigating through dense rainforest.
• River Safety: Trampers must be skilled in reading river conditions, as smaller side streams can become impassable after heavy rain.

Mountaineering and Climbing

The high alpine peaks around the headwaters of the Whataroa River are popular destinations for mountaineers. Climbers use the river valleys as access routes to climb glacier-covered peaks in the Southern Alps, including routes leading toward the Main Divide.

Whitebaiting and Fishing

During the springtime whitebaiting season (which runs under strict conservation rules), local fishers set up nets along the tidal reaches near the river mouth. They catch tiny migratory fish that swim into the river from the sea.

Anglers also visit the river to fish for brown trout in clear pools and side channels during the official fishing season.

Conservation and Environmental Protection

Protecting Native Biodiversity

The land surrounding the upper Whataroa River is protected as part of New Zealand's conservation estate, managed by the Department of Conservation.

Major conservation work includes:

• Predator Control: Trapping and monitoring introduced mammalian predators such as stoats, possums, and rats that threaten native bird eggs and chicks.
• Weed Management: Controlling invasive non-native plants (such as gorse and broom) that can take over natural gravel riverbeds where native birds nest.
• Protecting Braided River Birds: Rare birds like the black-fronted tern and banded dotterel nest directly on open gravel bars, making them vulnerable to disturbances and high floods.

Respecting the Wilderness

Visitors to the Whataroa River region are encouraged to follow "Leave No Trace" principles to protect the environment:

• Carry out all rubbish and waste.
• Stay on established tracks where possible.
• Respect native wildlife and keep a safe distance from nesting birds.
• Clean all boots and outdoor gear to prevent spreading invasive water weeds and plant diseases.

Key Facts Summary