• Overview
  • Water Services
  • CatchmentSIM
  • TRIM

Catchment Simulation Solutions provides engineering consulting services in the water field with a special focus on hydrologic and hydraulic modelling. 

We also develop and market several software product in this field, including our flagship product CatchmentSIM for mapping subcatchments and creating hydrologic models. We also develop TRIM, a complete simulation manager for TUFLOW.


CSS has considerable expertise in a full suite of flood-related disciplines. We strive to provide our clients with access to the latest available software, systems and modelling tools to improve efficiency and deliver innovative and timely outcomes. We are familiar with a range of 1, 2 and 3-dimensional hydraulic software, lumped and distributed hydrologic software and GIS software. This includes:

Hydrologic Models

    • WBNM
    • RORB
    • GSSHA
    • ICPR
    • URBS
    • HEC-HMS

Hydraulic Models

    • TUFLOW
    • RMA-2
    • RMA-10
    • HEC-RAS
    • ICPR
    • MIKE-11

Water Quality Models

    • MUSIC
    • Source Catchments


  • MapInfo
  • ArcGIS
  • MapInfo
  • WaterRide
  • CatchmentSIM

 Some of our sample projects are shown below.

Sample Projects

  • Campbelltown Flood Study +

    CSS was engaged by Campbelltown City Council to prepare a detailed flood study for the Campbelltown Locality. The purpose of the flood study was to define flood behaviour for existing and future conditions. In accordance with the requirements of the NSW Government's Floodplain Development Manual (2005), both mainstream and overland flooding needed to be considered as part of the study.
    Read More
  • Sydney Harbour Subcatchment Delineation +

    CSS were engaged by the Sydney Metropolitan CMA to complete subcatchment delineation for the Lower Parramatta River, Lane Cove River and Middle Harbour catchments, which occupy approximately 350 km2 of the Sydney urban area.  The project was completed as part of the Sydney Harbour Water Quality Improvement Plan.
    Read More
  • Parramatta River Source Catchments Modelling +

    CSS was engaged by the Sydney Metropolitan CMA to prepare Catchment Pollutant Export Models (CPEM) for the Upper and Lower Parramatta River catchments. The CPEM were developed for the Sydney Harbour Water Quality Improvement Plan using the Source Catchments software.

    Read More
  • The Hills Urban Overland Flowpath Mapping +

    CSS were engaged by The Hills Shire Council to map all urban overland flow path alignments in The Hills Shire Council LGA. The purpose of the study was to help identify all allotments that may be traversed by an urban overland flow path and which may be subject to a flood-related development controls (i.e., flood control lots).

    Read More
  • Fannie Road Bridge Upgrade +

    CSS were engaged as subconsultants by The Balmoral Group USA, to complete the hydrologic and hydraulic analysis for the proposed upgrade of the Fannie Road Bridge crossing of Big Escambia Creek in Escambia County, Florida. 

    Read More
  • 1

CatchmentSIM is a powerful software package for hydrologic analysis of terrain including mapping catchments, flowpaths and integration with hydrologic models.
  • Create a DEM from a wide range of data sources.
  • Remove flat and pits from the DEM using advanced filling and breaching algorithms.
  • Map the drainage path for any point in the terrain.
  • Automatically delineate stream networks complete with Horton ordering and full range of hydrologic attributes.
  • Automatically breakup a catchment into a subcatchment network.
  • Automatic calculation of subcatchment impervious proportions.
  • Integrates with 12d to map drainage catchments for pits and other structures in urban environments.
  • Use bathymetry and lake data to develop stage – area – volume relationships for reservoirs and lakes.
  • Chart a wide range of hydrologic attributes of subcatchments.
  • Visualise your project with 3D OpenGL graphics.
  • Export to GoogleEarth for powerful presentations.
  • Seamless integration with any external software via a macro language. Buit-in scripts allow creation of files compatible with a wide range of software.





Read More

TUFLOW Run Interface Manager (TRIM) is an application to help manage your TUFLOW model runs more efficiently.

  • Easily add any number of TUFLOW models to your queue.
  • Automatically run your models in sequence with any number of simultaneous runs (TUFLOW and TIRM license dependent)
  • Get Email or Skype messages when models finish
  • Add models and check status remotely via Skype
  • Simple progress bar and grid display allows rapid visualisation of model queue progress and model health
  • Easily test one or more models prior to running the entire queue.
  • Charts inflows, outflows and errors on the fly for each simulations.
  • Easy access to log files, key files and directories via right click menu.





Read More

CatchmentSIM Update & FMA Presentation

We are pleased to announce a new release of CatchmentSIM that brings Kriging and Natural Neighbour Interpolation to the Rainfall Analyser module and the Interpolate Grid from Points tool. These methods offer improved interpolation for rainfall observations and most types of point data. Click the Read More link to see some examples of how significantly rainfall isohyets can vary based on the interpolation method.


We are also happy to release our paper and presentation from this year's Floodplain Management Authorities conference in Brisbane. The paper discusses how we tackled the problem of applying freeboards in areas of overland flooding. This is an important area of research considering the increasing focus on flood risk in urban catchments. Some further information is included in the Read More link.

Rainfall Analyser


CatchmentSIM Rainfall Analyser Launch

We are pleased to announce the launch of CatchmentSIM's Rainfall Analyser module. This tool is the perfect accompaniment to CatchmentSIM to aid in the preparation of hydrologic models with full spatial interpolation of historical rainfall. 

Rainfall Analyser


TRIM: Manage TUFLOW Simulations Across a Cluster of Computers

We're pleased to announce the latest version of TIRM (2.6.0) now allows a simulation queue to be distributed over a cluster of modelling computers and managed from a single location. This ensures optimum TUFLOW license utilisation and modelling speed. TRIM will prioritise simulations to the fastest and most appropriate computers and notify if they go offline for any reason. We have prepared a quick 5 minute video that outlines the new feature and important considerations when using it. 

Click here to watch the video.

You can also download a free 45 day trial of an 8 simultaneous simulation version of TIRM from our website.

TRIM Server


Finding New High Ground in Emergency Response Planning Classification

Recently, we've been undertaking some interesting research on applying Emergency Response Planning (ERP) classifications at much finer scales than previously possible. This has been achieved by the use of automated analysis using an adaptive road network algorithm that senses when a road becomes impassible in a flood and searches for an alternative route. CSS Principal, David Tetley presented this work at the 2014 Floodplain Management Authorities conference in Deniliquin and received a Highly Commended Paper award.

Click here to read the paper and/or view the presentation. If you're too busy, click Read More below for a brief summary.

Rainfall Analyser


Free Licenses for Australian University Students

We are pleased to announce that CatchmentSIM is now freely available for students at Australian Universities. 

To register, please contact us. Proof of enrollment will be required.

Please note that these licenses are granted for educational and research purposes and are not suitable for commercial consulting undertaken by Universities.