When you first install WINFAP

  • You will need to download the latest National River Flow Archive (NRFA) Peak Flow Dataset from the NRFA website.
  • Register the NRFA Peak Flow Dataset using Options>Peak Flow Datasets...

Remember to download and register the latest dataset when it is released.

Starting a new project

  • You will need FEH catchment descriptors for your Site of Interest in the form of an FEH XML file.
  • For an ungauged site, you will need to purchase and download a catchment FEH XML file from the FEH Web Service.
  • FEH XML files are freely available for many gauged sites in the NRFA Peak Flow Dataset.
  • Import your FEH XML file for your Site of Interest using File>Import Site...
  • For a gauged site, any FEH annual maxima (.AM) and/or Peaks over threshold (.PT) data files associated with your catchment are loaded automatically.

Opening an existing project

  • You can open an existing project using File>Open Project.
  • You can also start a new project at any time using File>New Project.


Right click on your site in 'Site of Interest' to select an analysis method. The method you use will depend on whether you have suitable flow data for your Site of Interest.

For ungauged sites:

For gauged sites:

  • Use Pooled & QMED Analysis to add at-site flood data to your pooled and/or QMED analysis. This includes options for FEH Enhanced Single Site (ESS) analysis. The best-practice default method is selected automatically.
  • Use Single Site Analysis to analyse at-site flood peak data in isolation of other sites.
  • Use Historic Data Analysis to extend at-site records with information on flood events that occurred prior to formal measurement.

Tip: WINFAP 5 provides estimates for one Site of Interest within any given project. However, multiple instances of WINFAP 5 can be run concurrently allowing easy management of project data where estimates at multiple sites are required.