Success story

Reviewing Nutrient Limit Setting and Lakes Management Plan in the West Coast

Under the NPS-FM, Councils are required to follow the NOF for freshwater management. A key component of this is baseline attribute state setting, which involves the values (e.g., water quality) measured and monitored to determine the current state of a waterway.

Prior to A2E’s support, an expert panel was commissioned to provide technical advice and information around how WCRC would go about establishing baseline attribute states.

The resulting methodology covered the four following topics:

1. Identification of science attributes for implementation of the NOF.
2. A description of the process used to develop and map river classes, including a summary of modelled current state information for those classes.
3. Measured and modelled data used by the expert panel in their current and baseline state assessment.
4. Estimates of baseline states for river attributes in the West Coast Region.

However, budget and time constraints meant that the resulting methodology was not verified for accuracy.

Through A2E’s guidance, Dr Roger Young (Cawthron Institute) reviewed and verified the methodology created by WCRC and their appointed panel.

A range of advice and recommendations was provided, including:

• The approach to attribute setting is generally acceptable, with recommendations for additional attributes not considered by the panel (e.g., Lake Trophic Index, water quality, and water temperature).
• The mapping process recommended – based on source of flow – is useful for implementing policies.
• Modelling data was found to be of reasonable quality, with Dr Young highlighting a range of data-based issues for WCRC’s consideration.
• The process for estimating of baseline states for river attributes was sensible and robust and is expected to provide WCRC with useful information.

WCRC also requested expert advice for the development of a lake management framework. Dr Kirill Shchapov (Cawthron Institute) identified a range of parameters for WCRC to consider, recommending a framework that prioritises altitude and the percentage of agricultural land in the lake catchment area as key components.

A2E’s expert advice meant the methodology created for establishing baseline attribute states is verified for further development. Recommendations around processes, data quality and analysis will help refine WCRC’s approach as they set out to follow the roadmap to freshwater management outlined in the NOF.