Last updated November 2026
The Upper Nihotupu Dam walk is a short outing in the Waitākere Ranges that leads from Piha Road to one of Auckland’s oldest water supply dams. It starts with a brief stretch of forest track, then follows a metal service road down the valley past rapids and waterfalls to the foot of the dam.
Freewalks.nz gives about 35 minutes from Piha Road to the dam, and Tripideas describes the walk as gentle, without steep climbs. At the end you can follow old tram rails to the base of the dam and possibly climb steep steps to the top for views over the reservoir.
Practical Information
- Start
- Piha Road, Waitākere Ranges
- Distance from the city
- About 20 km from Auckland
- Walking time
- About 35 minutes from Piha Road to the dam, one way
- Track type
- Short forest track, then a metal service road to the dam
- Terrain
- Gentle walking; steep steps if you climb to the top of the dam
- Dogs
- Not stated on the official pages; check Auckland Council’s dog rules for the Waitākere Ranges Regional Park before you bring a dog
- Managed by
- Auckland Council (Waitākere Ranges Regional Park); the dam is run by Watercare
- Status
- Check Auckland Council’s open and closed tracks map before you go.
About Upper Nihotupu Dam Walk
This is a walk with a clear goal: a tall concrete dam tucked into a steep bush valley. The first part is a short section of forest track off Piha Road. After that the route joins a gravel service road, which makes for easy walking as it drops towards the reservoir.
On the way down the path runs beside rapids and past three waterfalls. Tripideas puts one of them at roughly 15–20 metres. Tripideas notes that you can carry on for about another 10 minutes beyond and below the dam to a cleared area where a bush tram once ran, then follow the old rails to the base of the dam.
From the base, steep steps lead up the dam face. Tripideas says you may be able to climb them and walk along the top of the dam, with views over the reservoir and down the valley to the south-west. If you can’t, turn around and head back the way you came.
The walk suits families and anyone who wants a taste of the Waitākere Ranges without a long tramp. Remember the return leg is uphill along the service road.
The Dam and Its History
Watercare calls Upper Nihotupu Dam Auckland’s second oldest water supply dam, and its highest and coldest. The concrete dam stands 50 metres high and is 162 metres long at its crest. It holds about 2.2 billion litres, and on average sends about 22 million litres of water a day by gravity to the Huia Water Treatment Plant. It runs off the grid, with power from micro hydro turbines and a solar panel.
The dam took eight years to build. Wikipedia records that the job was tendered in 1915 and went to Langlands and Company of Gisborne.
The First World War brought shortages of both labour and materials, and Watercare describes how sand, cement and coal came by barge from Onehunga across the Manukau Harbour to a wharf at Big Muddy Creek. The dam was officially opened on 14 April 1923.
The Nihotupu Tramline was built to serve the construction work and was later used for the Rainforest Express tourist ride. Watercare closed the tramline to the public permanently in November 2014. The catchment has also been a filming location for Hunt for the Wilderpeople and Mr Pip.
Before You Go
Auckland Council asks visitors to respect all closures, leave barriers and signs in place, and avoid spreading kauri dieback disease.
Tripideas notes there is reasonable space for off-road parking at the start, but that it can get very busy on weekends and public holidays.
Where to Learn More
Watercare: Upper Nihotupu Dam: 100 years old and still going strong: the dam’s size, history and how it supplies Auckland’s water.
OurAuckland: Waitākere Regional Park and tracks update: Auckland Council’s list of reopened and closed tracks in the Waitākere Ranges.
Frequently Asked Questions
Where does the Upper Nihotupu Dam walk start?
On Piha Road in the Waitākere Ranges, about 20 km from central Auckland in a straight line.
How long does it take?
About 35 minutes from Piha Road to the dam, one way. Allow extra time for the walk back up and for climbing to the top of the dam.
Is it a hard walk?
Not really. It’s a short forest track followed by a gravel service road, with no steep climbs until the steps at the dam.
Can I walk across the top of the dam?
You may be able to climb steep steps to the top and walk along it. If not, return the way you came.
Can I bring my dog?
The official pages for this walk don’t say. Check Auckland Council’s dog rules for the Waitākere Ranges Regional Park before you bring a dog.
Are there waterfalls on the walk?
Yes. The path passes rapids and three waterfalls, one of them roughly 15–20 metres high.
Where can I check if the track is open?
Check Auckland Council’s open and closed tracks map before you go.
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