Water Framework Directive Hydromorphological Status

The survey classifies hydromorphological condition using WFD nomenclature: High, Good, Moderate, Poor, Bad. Its typical use is to support the designation of high ecological status sites. Other applications of the RHAT method include assessing hydromorphological pressures, determining enhancement/restoration works required and pre-/post- works conditions for specific projects. Research and Operations teams based in Inland Fisheries Ireland have been using the RHAT methodology to assess habitat condition across various sites and catchments of interest.The OPW Environmental River Enhancement Programme (EREP) uses the RHAT methodology to collect hydromorphology data on a catchment-wide basis using a Survey123 RHAT form. Further detailed information on these surveys is available in the annual reports, which can be found on the website.

For more information on the RHAT methodology see the following references:

RHAT Training Manual (daera-ni.gov.uk) ISBN: 978-1-907053-65-8

River Habitat Survey (Environment Agency 2003, Raven et al., 1998)

Field Name 

Field Alias

Field Type 

Field Description 

catchmentWaterbody

Catchment/ Waterbody Name

String

Name of watershed unit

river

River Name

String

Name of river reach

rhatSpck

RHAT or Spot Check

String

Full RHAT survey or spot check survey (see RHAT manual)

surveyDirection

Survey direction

String

Direction walked from the survey starting point

dateSurvey

Survey Date

Date

Date of the survey 

sumAttributeScores

Sum of attribute scores

Double

Sum of the eight RHAT attributes (range is 0-32) 

wfdClass

WFD class

String

WFD class which corresponds to the sum (High, Good, Moderate, Poor, Bad)