General Information

SWASH is the acronym of Surface WAter Scenarios Help. It is a user-friendly software shell, developed to perform the so-called Step 3 FOCUS runs for the FOCUS Surface Water Scenarios. It was developed by Alterra, in close co-operation with W!SL, the Wageningen Software Labs, both located in Wageningen, the Netherlands.

The SWASH development team consists of (in alphabetical order):
Erik Van den Berg (Alterra)
Johnny te Roller (W!SL)
Mechteld ter Horst (Alterra)
Paulien Adriaanse (Alterra)

The SWASH Developers co-operated with the developers of the various tools that are linked to the SWASH shell. These are:

  • For the drift calculator: Denis Yon (Dow Agrosciences, UK) and Mark Russell (Dupont Crop Protection, USA)
  • For MACRO: Nick Jarvis (SLU, Sweden)
  • For PRZM: Mark Russell (Dupont Crop Protection, USA) and Mark Cheplick (Waterborne Environmental, USA)
  • For TOXSWA: Wim Beltman, representing the TOXSWA development team (Alterra, NL)


Short Model Description

Main functions of SWASH

SWASH is an overall user-friendly shell, encompassing a number of individual tools and models, involved in Step 3 calculations for the FOCUS Surface Water Scenarios. Its main functions are:

  1. Maintenance of a central pesticides properties database for use in MACRO, PRZM and TOXSWA
  2. Preparation of other input for MACRO, PRZM and TOXSWA, notably application patterns, application methods and dosages
  3. Creation of projects, containing all Step 3 FOCUS runs required for use of a pesticide on a specified crop
  4. Calculation of spray drift deposition onto ditch, stream and pond like waterbodies
  5. Provision of an overview of crop and waterbody combinations in each scenario, of the extent of each scenario and of the installed versions of each model, including its shell and database.

Short description of the SWASH software package

SWASH is aimed to create and link the runs of the various models in an easy and consistent way. With the exception of the Drift Calculator SWASH does not perform any model simulations, so the user should run himself the MACRO, PRZM and TOXSWA models. First pesticide entries via spray drift and drainage or runoff/erosion need to be simulated. This is done by the Drift Calculator (embedded in SWASH), and the MACRO or PRZM model, respectively. Next TOXSWA simulates the behaviour of the pesticide in the FOCUS water bodies. Pesticides can enter the waterbody by two entry routes only: spray drift plus either drainage or runoff.

See the following figure, illustrating the sequence of tools and models used to calculate pesticide exposure in the Step 3 EU FOCUS Surface Water Scenarios.

The SWASH User Interface was developed as a user-friendly environment for preparing input for the FOCUS models and make them communicate in a robust way. The interface is an integrated environment for data storage, data retrieval, drift deposition calculations and calling of models.

SWASH, MACRO, PRZM and TOXSWA must be installed in an agreed directory structure to enable the communication between the various models. The user interface is linked to a relational database for easy data access. It reads and writes data into one of the MACRO databases and reads and writes several input files for PRZM. TOXSWA makes use of the SWASH database. The FOCUS input is stored and locked in the SWASH database. The user can generate an overview of all needed runs for a desired compound-crop combination with a FOCUS wizard.


Role and Place in FOCUS scenarios calculation

SWASH is designed for Step 3 FOCUS runs and the FOCUS Surface Water Scenarios Working Group recommends the user to perform all Step 3 FOCUS runs with SWASH, i.e. to always have SWASH prepare input for all FOCUS runs and start the individual models via SWASH. The FOCUS wizard in SWASH prepares projects composed of runs for all valid crop-scenario-waterbody type combinations, while the user-defined wizard allows the user to make a selection out of these FOCUS combinations.

The SWASH tool may also be useful for refined risk assessment calculations of Step 4 by editting the input files prepared by SWASH outside the shells of the MACRO, PRZM and TOXSWA models.


Current use outside FOCUS

The SWASH tool was designed for Step 3 calculations for the FOCUS Surface Water Scenarios. It is also useful for Step 4 calculations for the FOCUS Surface Water Scenarios. No use outside FOCUS has been foreseen.

Excerpt of existing model documentation

  • (2017-01-16)  F. van den Berg, W.H.J. Beltman, P.I. Adriaanse, A. de Jong & J.A. te Roller, 2015. SWASH Manual 5.3 - User's Guide version 5. WOt-Technical Report 36. Wettelijke Onderzoekstaken Natuur & Milieu, Wageningen.
  • (2017-01-16)  Roller, J.A. te, F. van den Berg, , P.I. Adriaanse A. de Jong & W.H.J. Beltman, 2015. Surface Water Scenario Help (SWASH) version 5.3. Technical Description. WOt-Technical Report 27. Wettelijke Onderzoekstaken Natuur & Milieu, Wageningen.
  • Van den Berg, F., P.I. Adriaanse and J.A. te Roller, 2003. Surface WAter Scenarios Help (SWASH). Version 2.0. User's Guide version 1.3. Alterra-rapport 507. Wageningen, Alterra Green World Research, the Netherlands.
  • Roller, J.A. te, F. Van den Berg,and P.I. Adriaanse, 2003. Surface WAter Scenarios Help (SWASH). Version 2.0. Technical Documentation version 1.3. Alterra-rapport 508. Wageningen, Alterra Green World Research, the Netherlands. 

Download SWASH

Download SWASH

Latest version : FOCUS_SWASH_5.3

Package FOCUS_SWASH_5.3.zip (22/May/2015, 1 file)
Test Results SWASH_5.3 has been checked in combination with SPIN_2.2 and SPIN_3.3 according to protocol for installation and communication requirements of SWASH as adopted by FOCUS Version Control
Getting Started You need to install SPIN before installing SWASH. The default directory for SWASH is C:\SWASH. You can also choose another drive, for example D or F. In case you select
                                 another drive than C, the other applications should also be installed on that drive on subdirectories of the SWASH directory. For example if you have installed SWASH on
                                 D:\SWASH the other applications should be installed at:
                                 -    TOXSWA: D:\SWASH\TOXSWA
                                 -    MACRO: D:\SWASH\MACRO
                                 -    PRZM: D:\SWASH\PRZM
Comments 22/May/2015: The tool facilitates the calculation of metabolite PEC as described in  Generic guidance for Surface Water Scenarios, version 1.4 in addition to facilitating the active substance PEC calculations.
Important note: After creating the runs with the wizards and clicking view and edit applications, ensure that after editing CAM values for runoff scenarios and or application rates, that you click the save button, before the close button. Failing to do this, results in any edits made to application rates or CAM settings being lost. Unfortunately this shell release does not prompt that you need to save, before it accepts the instruction to close given by the close button.

03/June/2015: Important note: The user should be aware that when creating a single application project from a multiple application project, in addition to the default crop application window being included in the single application project, the default CAM method for run-off scenarios is also used when creating the single application SWASH project. The user should therefore ensure that they appropriately edit their single application projects generated this way by the tool, to ensure they get their required crop application window, CAM setting and application rate in the resulting simulations. I.e. the single application project generated by SWASH from a multiple application project is a useful prompt that single application simulations are needed, but the application windows, CAM and application rate initially presented in the project are just suggestions. These need to checked by the user and manually edited when any of the suggested  values are not those needed to generate simulations that comply with the version 1.4 and above generic guidance for surface water scenarios.    

17/June/2015: Warning: The copy function on the application form in SWASH v5.3. does not work correctly. After clicking on the “Copy” button, the application method is copied to the other runs in the project, but after clicking on “Save” and closing the form, the change of application method is not retained by SWASH. The work around is to change the application method manually one at a time for each run in the project and then press the “Save” button.

24/Jan/2019: Warning: SWASH transfers an incorrect value of the enthalpy of vaporisation from SPIN to PRZM. The enthalpy of vaporisation transferred to PRZM is 17.5 times too high, it is 397.1 kcal/mole instead of the default of 22.7 kcal/mole or 95 kJ/mole. The error is due to a wrong conversion from kJ/mole to kcal/mole in SWASH. The enthalpy is used to correct the Henry coefficient in PRZM for the temperature of the soil. The Henry coefficient represents the equilibrium between the vapour and solute phases and influences vapour-phase transport. PRZM uses the entered saturated vapour pressure assuming a reference temperature of 25°C. For 5°C lower, hence 20°C, the higher value of enthalpy of vaporisation results in an underestimation of the Henry coefficient of a factor 10-11 and thus in a severely underestimated vapour phase transport in soil. For 5°C higher, hence 30°C, the higher value of enthalpy of vaporisation results in an overestimation of the Henry coefficient of a factor 10+11 and thus in a severely overestimated vapour-phase transport in soil.  For volatile substances underestimated vapour-phase transport in soil will underestimate the movement of the substance back up to the runoff and erosion zones, and air above the soil. So runoff and erosion of substance mass may be underestimated. For non-volatile substances (saturated vapour pressure < 10-5  Pa and solubility > 1 mg/L, both at 25°C) and soil temperatures below 25°C (most of the time in scenarios), the expectation is the effect will be negligible because these substances are non-volatile at 25°C. The magnitude of the effect can be evaluated by entering an enthalpy of vaporisation 17.5 times too low in SPIN or in the PRZM input file. The error will be corrected in the next release of SWASH

08/Nov/2019: Correction of note of 24/Jan/2019 PRZM 4.3.1 always uses a default value of 22.7 kcal/mole for the enthalpy of vaporisation, even when the user has entered another value in SWASH. So, the bug in SWASH reported on 24 Jan 2019 does NOT have any effect on the calculated exposure concentrations. Note that this was discovered only after posting this bug on the FOCUS website on 24/Jan/2019. PRZM always overwrites the enthalpy of vaporisation transferred by SWASH. In the next version of PRZM this should be changed to result in PRZM using the value transferred from SWASH.

06/Jan/2022: Warning: after accessing the Applications window always export the project before running FOCUS_TOXSWA. If you close the Applications window without exporting it, the spray drift deposition values in the project are set to a default value of 100% in the database (this also happens when no changes were made to the applications). If you don’t export the project, when TOXSWA starts to run the project, 100% spray drift deposition is applied in the simulations, resulting in too high spray drift entries into the waterbody. Therefore, after closing the Applications window export the project (on which spray drift deposition values are calculated and set in the database) to ensure the correct spray drift deposition values are used for your simulations. In the next version of SWASH the user will be prompted  on closing the Applications window by a message that they need to export the project.


Previous version : FOCUS_SWASH_3.1

Package FOCUS_SWASH_3.1.zip (24/Nov/2009, 1 file, 30 MB)
Test Results SWASH has been checked according to protocol for installation and communication requirements of SWASH as adopted by FOCUS Version Control
Getting Started
Comments 19/Jun/2012: Users are advised to define application rates to not more than three decimal places for the unit kg, required by SWASH. I.e. in multiples of whole grams. If you wish to define application rates that include a fraction of a gram then please see Frequently Asked Questions on the documentation in FOCUS Surface water web page.
24/Nov/2009: Differences between FOCUS_SWASH_3.1 and FOCUS_SWASH_2.1: Word Document

Older versions: FOCUS_SWASH

Package FOCUS_SWASH_2.1.zip (15/Mar/2008, 1 file, 32.8 MB)
Test Results Results not very relevant as SWASH does not calculate exposure concentrations; SWASH has been checked according to "protocol for installation and communication requirements of SWASH" as adopted by FOCUS Version Control
Getting Started
Comments 15/March/2008: Differences between FOCUS_SWASH_2.1 and FOCUS_SWASH_1.1: Word Document

15/March/2008: Warning to SWASH users with Windows Vista: FOCUS_SWASH_2.1 is not Vista compliant. There is a problem with the way the main form of SWASH is displayed under the default Vista Aero theme. This will be fixed in the next release.
Package FOCUS_SWASH_1.1.zip (08/May/2003, 1 file, 12.3 MB)
Test Results (not available yet)
Getting Started
Comments 28/Nov/2003 : Warning to all SWASH and MACRO users :
There is a problem with MACRO runs for metabolites, defined with the ‘Detailed’ option on the ‘Sorption’ tab page in SWASH. The metabolite run with MACRO is performed with a Koc value of 0 for sorption onto soil, instead of the value entered in the SWASH shell under the heading ‘Soil’
Create, View and Edit Substances
tab sheet ‘Sorption’
put bullet: ‘Detailed’)
If the sorption capacity has been defined with the option ‘General’ (the most likely option) SWASH transfers the correct Koc value to MACRO.

16/April/04 WARNING : Problem with the use of SWASH with non-English versions of Windows :

Problem : User receives error message of SWASH-GUI: "Failed to update PRZM project file (przm.prj)", when clicking on the PRZM icon or "Write Substance Data" button in SWASH. Next, the user fails to import a SWASH project file in the PRZM shell. The reason is that SWASH fails to update the PRZM project file (przm.prj) for non-English language Windows versions.

Before SWASH starts PRZM, it updates the przm.prj file, that contains a list of all SWASH projects and their creation date. PRZM requires an English date format (i.e. dd-MMM-yyyy). However in some other language versions of Windows this date format is not a valid format, (e.g. the French version has jj-MMM-aaaa) and therefore SWASH fails to update the przm.prj file and the file remains empty.

This problem will be solved in the next release of SWASH. Up to then, the only solution is to use an English language version of Windows.

05/May/04 WARNING : potential error messages with the use of SWASH : After introducing a considerable number of substances or projects into the SWASH database, deleting some of these and next, re-creating some, two types of error messages may occur : read more ...

06/Jun/05 ERROR : A SWASH error which is in fact the same as the one reported as number 11 of the compilation list of known bugs for TOXSWA ; the user may have suffered from this error without noticing. Note : This error note makes reference to FOCUS_TOXSWA_2.2.1, which is under preparation, thus not officially released yet.

06/June/05 : NOTE :
The SWASH User’s Guide has been finalised and is available as pdf or as hardcopy (Alterra report). The "SWASH User manual" (Appendix H of FOCUS, 2001) has now appeared as: "F. van den Berg, P.I. Adriaanse, J.A. te Roller, 2005. FOCUS Surface WAter Help (SWASH) version 1.1. User’s Guide version 1. Alterra-rapport 507. Wageningen, the Netherlands". Compared to Appendix H some slight improvements have been made, e.g. an index and a ‘Day in year calendar’ have been added. You can download it or make a request for a hardcopy of the report at toxswa-swash@wur.nl

14/June/05 : Additional information about Repairing the SWASH database. :
In the SWASH warning dated 05/May/04 it is stated that MS Access version 97 should be used to Compact and Repair the database.

We now have the following information for you:

1. The SWASH software package is distributed in Ms Access version 97.
2. If you have a database problem contact marc.van-liedekerke@jrc.ec.europa.eu to obtain the password of the SWASH database.
3. If a user has a newer version of Ms Access (e.g. version 2000 or 2003), he can convert his database from Ms Access 97 to this newer version.
4. Next, in this newer version, he can select menu option Tools - Database Utilities. Use the option Compact and Repair Database. Close the database and restart using the SWASH database, after having checked that the database is still called SWASH_db.mdb and is located at the directory \SWASH\Data.

As said in the 05/May/04 warning, the background of this problem is that the database is sometimes not 'cleaned' properly by Ms Access, when many records have been deleted and/or re-created. Recognizing this problem the options Compact and Repair Database were added to the Ms Access software package.

The SWASH database is secured by a password to prevent users from messing up the database, thus causing a possibly incorrect behaviour of the SWASH User Interface.


Go Back To