Te Waikoropupū Springs is a precious taonga, a natural wonder renowned for its crystal-clear waters. However, increasing nitrate levels in the Springs have become a concern. To address this challenge, we have developed an initial Freshwater Action Plan.
Freshwater Action Plans aim to identify the range of actions and changes that might be needed to reach our goals for freshwater in a catchment.
In Tākaka, for Te Waikoropupū we have a goal from the Water Conservation Order process to reduce nitrate in the Springs to 0.41mg/L by 2038. This would return nitrate levels to what they were, on average as monitored, between 2007 and 2017.
The Tākaka Freshwater Action Plan needs to identify the causes of nitrate degradation and ways we can address these.
Freshwater Action Plans can identify new rules needed in Council plans, new investigations, monitoring, education and projects, as well as actions taken by other agencies – such as the Department of Conservation, and by community groups or individuals.
Some actions will need funding through the Long Term Plan process or require a plan amendment to promote change, while others may already be in progress by Council and landowners in the catchment.
Freshwater Action Plans are catchment-wide, which is different to the action plans that will be required as part of Freshwater Farm Plans, which are farm specific.
Current science on the aquifer and nitrate sources Farming land use in the recharge area has been identified as the largest contributor to nitrogen load to the aquifer, with geological, wastewater, quarry explosives and seawater also making some contributions. There may also be an association of nitrate levels with climate variability between La Nina and El Nino, however further monitoring data is needed to understand this (refer Cawthron report 4036, 2024(external link) for further information).
Farmers across the Marble Aquifer (FAMA) is a farmer led catchment group that has developed to support the Water Conservation Order. The group, administered by the Tasman Environment Trust, consists of in total 14 dairy farming families, 12 whose properties cover a large area of the Valley floor where waters enter aquifer recharge and 2 adjacent to Te Waikoropupū Springs.
The group has been supported by funding through Ministry for Primary Industries and Fonterra’s Living Water Program and is developing a comprehensive understanding of how to manage the farmed landscape in a manner that meets the needs of the order both now and into the future.
Changes to farming practices in the recharge area are currently a key method to reduce nitrate entering the aquifer.
There are still many unknowns regarding the complex aquifer system and the Council is working to both better understand how land use activities affect freshwater in the catchment and what can be done to reduce excess nitrate entering the karst systems.
The WCO sets the nitrate limit at the Main Spring at 0.41mg/L of Nitrate-Nitrogen (NO3-N) and our compliance assessment against this limit must use a 5-year rolling median of monthly data. We have previously collected data quarterly but began gathering monthly data at the Main Spring in June 2023. This means we will have 5 years of verified data in June 2028 at which point we can confirm how the compliance levels compare to the limit.
You can follow our monitoring results here.
Supporting the WCO and protecting Te Waikoropupū SpringsCouncil has several workstreams in progress to both improve our understanding of the nitrate issue and put in place changes to reduce nitrate in the aquifer and Springs.
Some of these actions were recommended by the Environment Court in it's report to the Minister for the Environment in 2023 that accompanied the recommended WCO. Some are specifically required by the Water Conservation Order, while others have come from previous work (e.g. Tākaka Freshwater and Land Advisory Group (FLAG)) and, new ones in response to the new nitrate limit.
The Tākaka Freshwater Action Plan will evolve over time as our understanding of the complex aquifer system and nitrate in the system increases. Key actions to ensure long-term sustainability are:
Water quality monitoring
Understanding the catchment, land use change and land use practices
Understanding the outstanding values to be protected
Potential future actions (may be funding dependent)
Other potential future actions (may be funding dependent)
If you would like to make comment on the Tākaka Freshwater Action Plan email us at Water Conservation Project.
