NZWaM - Hydro: Use and applications

NZWaM-Hydro is scalable, and the hydrological relationships in the model are transferable between locations.

The modelling framework could be used for:

National Policy Development

  • To derive hydrological indicators and signatures (e.g soil moisture, groundwater depth, snow depth)
  • Consistent time series of hydrological fluxes for ungauged catchments with water quality trend correction and spatial and temporal uncertainties
  • State of the Environment reporting for ungauged catchments
  • Derivation of water allocation rules 
  • National and regional water accounting
  • Regional scale calibration available for national policy development using one modelling framework

Regional Policy Development

  • Implementation of national policy and regional policy development based on regional model calibrations and fine tuning
  • Derivation of dynamic hydrological fluxes indicators (e.g soil moisture, groundwater depth, snow resource) across region
  • Tuned to support local water resource planning and associated uncertainties
  • Sub-regional refinement of water allocation rules
  • Sub-regional fine-tuning to produce consistent hydrological flux timeseries
  • Sub-regional State of the Environment report (integrated to national scale reporting that can be fine-tune based on local knowledge)
  • Sub-regional scale calibration available for implementation in regional and national scale models supporting policy development using one modelling framework

Water allocation and flow setting (with CHES and/or similar tools)

  • Catchment and regional-scale water allocation rule scenarios
  • Coupling hydro-model with contaminant loading to test implementation of environmental limits (e.g. social hydrology)
  • Impact assessment of water allocation on "integrated" water supply (surface water and groundwater)

Hydrological Investigation

  • Provision of dynamic boundary conditions for local-scale high resolution models
  • Derivation/estimation of hydrological flux return periods across New Zealand

Large-scale flow, flood and drought forecasting

  • Climate change impact assessment on water resources and hydrological risks
  • Regional and catchment flow forecasting through coupling with Numerical Weather Prediction models
  • Medium range forecasting of hydrological fluxes and flows
  • Seasonal range forecasting

Water quality investigation

  • Provision of flow corrections to assess water quality trends
  • Provision of flow and hydrological fluxes time series for dynamic contaminant load estimation

Designing water trading schemes

  • Estimation of cross region/catchment trading-schemes and their impacts on water resources and associated environmental limits (Manuherika/Taieri in Otago)