Tēnā koutou
Te Waihora/Lake Ellesmere is currently CLOSED to the sea. The calm average level at 0800 hrs on Monday the 3rd August was 1.21m
Update: Opening attempt
Crew and machinery have been working onsite.
Sea and weather conditions have been unworkable, with big swells, so focus of works has been on maintenance and protection of the opening area.
The forecasts continue to prove challenging, and it is unlikely sea conditions will allow an opportunity to attempt an opening until later this week.
Contactors will remain working on the site preparing for an attempt as soon as conditions allow.
Q: What was the lake level reading before this one?
A: 1.16m: The calm average level at 2000 hrs on Sunday 26th July.
Q: When was the lake previously opened to the sea?
A: The lake was mechanically opened on 10th July 2026 and closed naturally on 20th July 2026.
Q: At what levels can the lake be opened to the sea at this time of year?
A: From the 1st August to 31st March : 1.05 masl
A: From the 1st April to 31st July : 1.13 masl
Te Waihora/Lake Ellesmere levels are now available on our river flow data web page. These levels are average readings taken from the two gauges around the lake, one at Taumutu and the other at Seabridge Road/Nutts Cut. Please note that wind effect should be considered when interpreting this raw data. The wind information is currently not provided on the public web page; however, it may be requested by contacting Customer Services.
Click this link to go to the average lake level data webpage – https://www.ecan.govt.nz/data/riverflow/sitedetails/168307
Or, navigate to the site named Te Waihora/Lake Ellesmere (Average) from ECan’s river flow data webpage – https://www.ecan.govt.nz/data/riverflow
For more information on the mechanical opening of Te Waihora/Lake Ellesmere, please visit our web page here: https://ecan.govt.nz/your-region/your-environment/river-and-drain-management/opening-te-waihoralake-ellesmere/
Lake level trend over the past 8 weeks (using the average values provided in the weekly email updates):
Water levels are reported as metres above sea level (masl), these levels are relative to the Lyttelton 1937 datum.
Water levels are reported as metres above sea level (masl), these levels are relative to the Lyttelton 1937 datum.
24/7 access to Te Waihora/Lake Ellesmere water levels:
Please note that wind effect should be considered when interpreting this raw data. The wind information is currently not provided on the public web page; however, it may be requested by contacting Customer Services.
Click this link to go to the average lake level data webpage – https://www.ecan.govt.nz/data/riverflow/sitedetails/168307
Or, navigate to the site named Te Waihora/Lake Ellesmere (Average) from ECan’s river flow data webpage – https://www.ecan.govt.nz/data/riverflow
For more information on the mechanical opening of Te Waihora/Lake Ellesmere, please visit our web page here: https://ecan.govt.nz/your-region/your-environment/river-and-drain-management/opening-te-waihoralake-ellesmere/
Q: Where can I find the resource consent for the lake opening?
A: The Hearing Commissioners decision on the new joint resource consent application by Te Runanga o Ngai Tahu and Environment Canterbury was received on Wednesday 22 January 2014. The decision was to grant the application for a period of 15 years subject to a suite of mitigation measures. You can read the decision here: RMA92023020 Decision – Final
Q: What lake opening investigations are being carried out as part of Whakaora Te Waihora?
NIWA and the University of Canterbury have investigated options for an engineered lake level. As part of this project a website has been created which summarises the options that have been considered over the years. There is further information here.