STOAT: Wastewater Plant Modelling Tool

The first choice for dynamic modelling of wastewater treatment plants, available as Freeware.

Looking for Plan-It STOAT: Wastewater Plant Design?

Jeremy Dudley is our expert in STOAT

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Dynamic wastewater simulation

STOAT is a PC based computer modelling tool designed to dynamically simulate the performance of wastewater treatment works (WWTW). Used worldwide, the software can be used to simulate individual treatment processes or the whole treatment works, including sludge processes, septic tank imports and recycling. The model enables the user to optimise the response of the works to changes in the influent loads, works capability or process operating conditions.

WRc has also collaborated with major US company CDM to develop Plan-It STOAT, a tool which assists experienced plant designers to address hydraulic and process capacity, cost, and footprint.

Supportive user experience

Features include a user-friendly interface, easy data transfer with other packages, support for batch simulations, and options for a quick build wizard. 

Allows for varied integration

STOAT integrates with leading sewerage and river quality models and allows simplified sewer modelling (WRc's SIMPOL ICM provides a more comprehensive sewer modelling system, if required).

Extensive modelling options

Offering both Biological and Chemical Oxygen Demand (BOD and COD) models, STOAT simulates all common (and some less common) treatment processes.

Compatible with external interfaces

STOAT provides support for data exchange with other programs, using either a COM interface or the standardised OpenMI water sector interface.

Download STOAT for free

Start optimising and troubleshooting your WWTW operations with our user-friendly, integrated package for Windows.

Download now
I used STOAT for modelling complex sewage treatment works which required modifications to be made to allow full nutrient removal. It allowed us to unravel the complexity and gave us confidence in decisions regarding the best way forward.

David Johnstone - Wastewater Treatment Process Technology Consultant

Benefits and outcomes

  • Improve effluent quality, reducing risk of consent failures
  • Reduce capital and operational costs
  • Design treatment plants more efficiently
  • Optimise treatment plant operation
  • Troubleshoot operational problems
  • Carry out integrated catchment simulation
  • Train staff in best practices

Wastewater plant features included in the package

Related case studies

In-depth design tool: Plan-It STOAT

Do you require rapid screening of proposed designs that might be infeasible on the grounds of cost, land area required, or treatment performance? 

Use Plan-It STOAT to optimize your wastewater treatment operations like never before.

Read more

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Created by potrace 1.16, written by Peter Selinger 2001-2019
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Jeremy Dudley

Consultant Engineer (Treatment Processes)

Jeremy's expertise lies in the modelling of sewage treatment systems; activated sludge systems; and modelling of processes and hydraulics at sewage and industrial effluent treatment works, both in the UK and overseas. He is the lead developer of WRc's dynamic wastewater modelling tool (STOAT) as well as the steady-state design version of STOAT (Plan-It STOAT). He is also involved in the development of WRc's cost and carbon modelling software (TR61).