The method was initially developed and implemented by a group of geomorphologists, ecologists, statisticians and experienced environmental managers from across England and Wales.

The overall idea was to try to capture in a quantitative or semi-quantitative way the physical diversity of rivers. The survey methodology was based on fluvial geomorphology and ecology. The focus of the survey methodology did not provide an inventory of features specifically linked to known species but to record forms and habitats that are the results of natural geomorphological and biological processes. The survey was applied to more than 24,000 sites in the UK and abroad.

The RHS field method is a systematic assessment of the physical structure of a watercourse. Data collection is based on a standard 500m length of river channel. Information is collected for each site, including grid reference, altitude, slope, geology, height of source and distance from source.

During the field survey, features of the channel (both in-stream and banks) and adjacent river corridor are recorded. In all, more than 200 compulsory data entries are made at each site, in the form of the presence, absence and (in some case) extent of specific features, collectively building a comprehensive picture of habitat diversity and character. Both the map-derived and field data are computerised, thus allowing easy access to a database, and rapid analysis of the information collected.

To establish a community of RHS researchers, environmental managers and practitioners, a website has been developed to improve awareness and knowledge on species and habitats and their links to catchment processes and human activity.