For everyone who worked with Menyanthes
From Menyanthes to Phrea: map, time series and model together again.
The freely available version of Menyanthes is no longer supported. Pastas continues the time-series method behind Menyanthes as open source, but it is driven by Python scripts. Dawaco Phrea™ gives Pastas a complete graphical workspace for modelling (build, calibrate, assess, forecast): your wells on the map, models built on the measurements you already manage, with no programming.
Did you work with Menyanthes?
If you worked with Menyanthes, you may be looking for a future-proof way of working. Phrea offers a graphical workspace for Pastas, with the map alongside and on your own measurements.
What Menyanthes was
For many years Menyanthes was a widely used tool for groundwater time-series analysis in the Netherlands, used by water boards, provinces, municipalities, water utilities and nature managers.
What made it practical: wells on the map, measured series and time-series models in one program, operated without programming.
Where Pastas stands
Pastas continues the time-series method behind Menyanthes as open source. It is scientifically published, and Phrea respectfully uses it as its calculation engine.
Pastas is driven by Python scripts. Phrea adds the graphical workspace, with the map alongside, so you use the same method with the mouse.
Time-series modelling · module
Pastas, without scripts
Pastas with a graphical workspace to build, calibrate, assess and forecast, with your map alongside. No programming.
No scripts
Choose a well; KNMI precipitation and evaporation are found for you, and you calibrate in one click.
Explain
See which part of the level comes from net recharge (precipitation and evaporation together) and which part from an abstraction.
Look ahead and ask what-if
Forecasts with an uncertainty band and scenarios next to the baseline. Projected GxG is always labelled “projected from a model simulation, not measured”.
Some features are available as add-on modules. Time-series modelling is available as a module.
The map
The map belongs to it
Your wells on the map, the model beside its well. Pick a well on the map and you see its model; compare it with its neighbours in the same area. A time series always stays connected to the place where it was measured.
A map view of model characteristics per well is something you request in plain language (add-on module AI assistant). The judgement stays with the hydrologist.
More about the AI assistant
Scale
From one well to a whole area
Build models for many wells at once, and keep them current.
The work you used to do well by well, you now do for a whole selection. New measurements come in, and with scheduled recalibration the models stay current.
See it in the demoOpen
Open, so never locked in
Your models stay yours, and they sit next to the rest of your groundwater work.
Open and reproducible
Every result can be retrieved, and every model exports to Pastas’ own file format, so you can always continue in Python.
One product
Models run on the same measurements you manage and validate in Phrea, alongside the BRO chain and the AI assistant. No exports between packages.
A familiar source
Menyanthes could read data from Dawaco, among other sources. Once your measurements are in Phrea, nothing needs to move for a model: measurement and model live in the same system.
Moving to Phrea
FAQ
Frequently asked questions
Is Dawaco Phrea™ an alternative to Menyanthes?
Yes, for time-series analysis of groundwater levels. Phrea uses Pastas as its calculation engine and gives it a complete graphical workspace for modelling (build, calibrate, assess, forecast), with the map alongside. It is not a new version of Menyanthes, and not a copy: you work in one product that also covers your monitoring network, validation and BRO delivery.
Is Menyanthes still supported?
According to its own download page, the freely downloadable version of Menyanthes is no longer supported. For the status of other versions, please ask its makers.
What is Pastas?
Pastas is open-source software (MIT licence) for groundwater time-series analysis, scientifically published in 2019. It continues the time-series method that Menyanthes was also based on. Pastas is driven by Python scripts; Phrea adds the graphical workspace.
Do I need to program?
No. You build, calibrate, assess, forecast and run a scenario in Phrea with the mouse. If you do want to continue in Python, export the model to Pastas' own file format.
Can I transfer my Menyanthes models?
Not automatically: you rebuild models in Phrea. Because your series are then already in Phrea and the weather is already there, that is mouse work, not scripting. Series you hold as CSV or Excel files come in through the standard import.
Can I see the results spatially?
Yes. Your wells are on the map and the model sits beside its well, linked in both directions. A map view of model characteristics per well is something you request in plain language (add-on module AI assistant).
Is Phrea affiliated with Menyanthes or Pastas?
No. Phrea builds on Pastas as open-source software and credits it as its engine. Dawaco is not affiliated with the makers or rights holders of Menyanthes, nor with the Pastas project.
When and how can I start?
Dawaco Phrea™ is available from October 2026. Time-series modelling is a module.
Menyanthes and Pastas are named here descriptively. Dawaco is not affiliated with the makers or rights holders of Menyanthes, nor with the Pastas project.
See your own wells in a time-series model
In a demo we show the modelling on example wells and discuss your situation. Dawaco Phrea™ is available from October 2026.