Development of a Nation-wide New Zealand Model

Nitrogen/phosphorus balance model applied to the whole of New Zealand

Modelling of summer nitrogen and phosphorus concentrations in all New Zealand streams.

The National Institute of Water and Atmospheric Research (NIWA) calls on our company for the development of a New Zealand national operational water quality model.

The main achievements are:

- The development of a new Nitrogen (N) and Phosphorus ( P) balance model (Sparrow Refined) on the sub-catchment level applied to the whole country. Based on the SPARROW model, it will be included in the decision support system CLUES.
The system, written in R and C, is parallelised and and allows a relatively easy calibration and an application of the model on the 34 million units (under an hour).
This technology opens the way for testing relevant scenarios on water quality (N and P) on a national level.

- The simplified summer modelling of total N, total P, dissolved inorganic N and dissolved P in all New Zealand streams (non-instrumented).
This work calls on our expertise on Machine Learning approaches, and in particular on Boosted Regression Trees (BRT).