Hazards and navigation safety events

Here you'll find current information about hazards and navigation safety events in the Canterbury region.

Report an incident, accident or hazard

An 'incident' may be bad behaviour on the water, an 'accident' a boat crash, and a 'hazard' a log sticking out of the water.

To report a hazard or unsafe behaviour out on the water, please get in touch with our Harbourmaster's Office:

Alerts and hazards

Navigation safety alerts

  Navigation Safety Alert: Jet Skis at Sumner Bay Beach
Since mid-2020, the Harbourmaster’s Office has observed numerous instances of unlawful jet ski activity within the Reserved Area of Sumner Bay.

Power-driven vessels are prohibited in the reserved area of Sumner Bay. No power boating is permitted from the beach out to 400m where the reserved area ends, unless transiting directly from or to the nearest point outside the reserved area.

Notified hazards

Hazards notified to the Harbourmaster's Office are ones that are considered to be out of the ordinary for their location, rather than the kinds of things that any prudent vessel skipper or boatie would normally be looking out for. It should not be considered an exhaustive list of any and all hazards.

Lake Opuha, Fairlie

16 February 2024

With extremely low water levels, trees on the lake bed are becoming exposed or are sitting just below the surface. It is recommended that boaties navigate with extreme caution and slow their speed.

Railway irons below the surface of the Waimakariri River

5 February 2024

Railway irons have been reported just below the surface of the Waimakariri River upstream of Mount White by the railway bridge. Navigate with extreme caution.

Railway irons reported just below surface on Waitaki River

1 December 2023

A number of railway irons have been reported just below the surface of the Waitaki River when the river is at 500 cumecs.

The location is between the SH1 bridge and the Rail bridge, true left of the river. Please lower your speeds in the area and keep a lookout for hazards.

Submerged trees near the Waiau Uwha rail bridge

27 September 2023

A number of trees are stacked up against the rail bridge over the Waiau Uwha River.

Some of the trees are submerged and difficult to see. Please lower your speeds in the area and keep a lookout for hazards.


Large log in Waimakariri River

27 June 2023

There is a large log just below the surface of the Waimakariri River, just south of Burkes Point. The log has been marked with a red buoy and its approximate location is marked with a red GPS location marker on the map below. Please navigate with caution in this area.

GPS coordinates: 43 23.641S; 172 40.635E


Rockfall upstream of Rakaia Gorge Bridge

9 June 2023

We have received a report of a potential large rockfall approximately 4.5km upstream of the Rakaia Gorge bridge. Keep aware whilst navigating this area and do not stop in the vicinity.


Railway irons in the Waiau Uwha River

8 May 2023

We have had a report that there are exposed railway irons in the Waiau Uwha River in the region of Bruce's Groyne. There is also a 'sputnik' type of concrete/steel object in a channel a little way downstream. 

Railway irons in the Rangitata River

17 April 2023

Two railway irons have been spotted poking out of the Rangitata River. They are located in the main river flow, approximately 500m above the Rangitata River Bridge - SH1.

We will remove the railway irons as soon as possible. In the meantime, please stay alert and keep your speed low in the area.

Railway irons in the Waiau Uwha River

29 November 2022

Two sets of railway irons have been spotted poking out of the Waiau Uwha River, west of SH1. One set is in the middle of the river channel. The other set is on the north side of the river channel.

We will remove the railway irons as soon as possible. In the meantime, please stay alert and keep your speed low in the area.

Historic fencing may pose risk in Canterbury rivers

5 January 2021

Rivers including the Poulter, Waiau, Waipara and Okuku may be adjacent to historic fencing that could encroach on the waterways.

River users are advised to check the area they are boating in prior to using the river. Before entering the water please ensure you are aware of any hazards and take safety precautions to avoid getting entangled.

If you come across any man-made hazards on the river, please take a photograph with details of the exact location and send it to harbourmaster@ecan.govt.nz. If you are also aware of the contact details for the adjoining landowners, please also forward this information. We can then update our hazards page so the public is aware of any action being taken to remediate the issue.


Various waterways in the Canterbury Region

1 November 2018

Fluctuating water levels on various waterways, including rivers, lakes, and lagoons in Canterbury may result in fences, waratahs, or other objects being obscured from view and sitting below the surface. All water users are strongly recommended to exercise caution and keep your speed to 5 knots or less within 200 metres of the shore, unless the area is uplifted or has any other form of speed exemption. It is the responsibility of the skipper of the vessel to ensure that the area you are using is navigable and safe to transit.

Lower Clarence River / Waiau Toa - navigation safety hazards - sputniks

30 January 2015

Sputniks are large concrete blocks with protruding steel beams that were historically used on rivers for bank protection. Many still exist on some rivers, including several in the lower Clarence / Waiau Toa, some of which are navigation safety hazards for those boating the river. For more information see the Sputniks notice (PDF 710 kB).

Brooklands Lagoon - submerged objects

30 January 2015

Submerged and semi-submerged objects including tree stumps have been reported in the Brooklands Lagoon water ski area. Users of this area are advised to exercise caution as these objects may be difficult to see, particularly if navigating at towing speed.