Local Government Magazine

NIWA moves updated water modelling tool to test phase

Caption: The general CLUES menu on the right-hand pane in ArcGis Pro.

A catchment model that predicts the impact of land use changes on water quality has been rebuilt and its developers are looking for volunteers to test a beta release.

The Catchment Land Use for Environmental Sustainability (CLUES) model was developed by NIWA, Landcare Research, AgResearch, Plant and Food Research and Harris Consulting, and released in 2006. 

It has become a staple tool for national and regional water quality modelling and is available publicly for non-commercial use.

Catchment managers, land-use planners and regulators use it as a decision-support tool to inform catchment planning and policy development.

CLUES predicts instream loads of total nitrogen (TN), total phosphorus (TP), suspended sediment and E. coli for every reach in the River Environments Classification (REC) drainage network.

It has a geodatabase for current-state water quality modelling and has tools for creating land use scenarios and land management scenarios quickly and simply.

NIWA Urban Aquatic Scientist, Annette Semadeni-Davies, says CLUES has been developed as a GIS application to allow geo-visualisation of the model inputs and outputs. 

“We have been planning for the imminent retirement of ArcMap and in 2019 we asked users for their preferred platform options. ArcGIS Pro was the preferred option.”

Transition from the ArcMap GIS environment to ArcGIS Pro has required a rebuild of the model.

Semadeni-Davies and NIWA GIS Specialist (Hydrological Modelling) Ude Shankar have been working to produce a new version and are at the stage where they’re looking for volunteers to test CLUES Pro: Beta Release.

“We want to make sure it is intuitive and provides and displays the model outputs that meet the needs of our users,” says Semadeni-Davies. 

Some of the functions in CLUES are being replaced by new features. Modules have been coded for TN, TP and E. coli, and a new sediment module based on NIWA’s Sediment Yield Estimator is planned for 2024. 

There is a new-look dockable interface compatible with ArcGIS Pro and a national (rather than regional) database that allows simulations to be run in multiple regions simultaneously.

The spatial input data for CLUES has also been updated, including the latest version of the REC (v. 2.5) drainage network, and a new LCDB5 land use layer for the baseline year 2017.

The new version will have catchment selection and tracing tools that offer greater flexibility than those built into ArcGIS Pro. 

NIWA plans further work on CLUES before the full model release in 2024. Semadeni-Davies and Shankar are available to talk through the changes and are keen to speak with people who want to become beta users.


Contact Annette Semadeni-Davies (annette.davies@niwa.co.nz) or Ude Shankar (ude.shankar@niwa.co.nz). More information: www.niwa.co.nz/clues.

Related posts

Drought-stricken Auckland relies on WRC

LG Magazine

Water Reform- the New Zealand way

LG Magazine

Water reforms demand workforce upskill

Contrafed Publishing