1.   Purpose and objectives

     To analyse a set of annual maximum flood measurements for a site and predict flood size and frequency.

2.   Description

     WINFAP is a software package designed for use by hydrologists, planners and consulting engineers concerned with flood risk assessment and flood alleviation. It can be used to analyse a set of annual maximum flood records, and estimate both the size and frequencies of occurrence of floods 
that can be expected at a site. Alternatively the package can be directed at a particular flood magnitude, estimating how often it is likely to recur and setting it in a historical context. WINFAP can also be used to analyse maxima of other environmental variables such as wind speed and rainfall.

     Statistically WINFAP can use and amend stored information about annual maximum event data in order to estimate: the probable frequency of a particular annual maximum event recurring within a specified period; the probable magnitude of an event for a particular return period; the probable 
return period of an event of particular magnitude.

     WINFAP uses distribution and fitting methods that have proven to be particularly suitable in hydrology, and these are described and discussed in the manual. The user can study the sensitivity of estimates to both observations and choice of method.

     Analysis results can be shown as a frequency plot, a table or a histogram, on the PC screen or output to a wide range of printers and plotters.

3.   Input

     A set of annual maximum flood measurements for a site.

4.   Output

     Results to PC screen, printer or plotter.

5.   Operational requirements and restrictions

     WINFAP is a Windows® 3.1 compliant package. Minimum requirements are a PC with 386 processor, 4MB RAM and VGA monitor. Any Windows® supported hard copy device may be used for output.

6.   Form of presentation

     Software on disk and supporting manual.

7.   Operational experience

     Has been applied in various locations.

8.   Originator and technical support

     Software Sales and Support, Institute of Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire OX1O 8BB

9.   Availability

     The software is for sale. A free information pack is available from the UK HOMS Office, Centre for Ecology and Hydrology, formerly the Institute of Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire OX10 8BB.

10.  Conditions on use

     Software use subject to licence agreement.