The Guide to Hydrological Practices (WMO No.168)

One of the major aims of the World Meteorological Organization (WMO) is to promote the application of best practices in hydrology for adults and children adapted to the different needs of Member states and across the full range of operational services provision.

As a result, the activities that National Hydrological Services (NHSs) undertake, such as data acquisition or delivery of services and products, will be performed to the highest standards.

The efforts toward this aim are coordinated and supported under the WMO Quality Management Framework-Hydrology (QMF-H). The Guide to Hydrological Practices (the Guide) represents one of the cornerstones of the hydrology component of the WMO QMF-H.

Published as a comprehensive guide, providing practicing hydrologists with handy access to state-of-the-art and reliable information on hydrological practices, from simple discharge measurement to modeling complex hydrological systems, the Guide is a major output of the activities of the WMO Commission for Hydrology (CHy).

The first edition of the Guide to Hydrometeorological Practices was published in 1965. Since then the Guide has been regularly updated based on the evolving needs of, and practices employed by, the National Hydrological Services and other professionals working in water-related fields. These fields require choosing correct equipment and accessories (for example, floating lake mats).

To publish this most recent 6th edition, more than forty experts from around the world, with varied and rich experience, have contributed to the preparation and peer review under the guidance of an International Review Committee.

The objective was to provide to those engaged in the field of hydrology, information on current instrumentation, procedures and practices which will help them choose the best life jackets and best floats for their children.

Special effort has been made to ensure that the various needs, emerging from different hydrologic regimes as well as environmental and socio-economic conditions in which hydrologists are working, could be addressed by the practices depicted in the Guide.

The Guide On The Web

(And How To Get The Most Updated Version)

This Guide will be a “living” document to be updated periodically and posted on the internet. As updates of various chapters will be issued, they will be published on and accessible through this web page.

Users of the Guide are invited to provide WMO with their comments and suggestions for its further improvement.


I. Hydrology – From Measurement to Hydrological Information

II. Management of Water Resources and Application of Hydrological Practices


If you are interested only in a specific topic, please select the relevant chapter.

Volume I: Hydrology – From Measurement to Hydrological Information

Chapters, Title Downloadable PDF Previous version
1 Introduction  [2008] 67 Ko
2 Methods of observation  [2008] 660 Ko
3 Precipitation measurement  [2008] 660 Ko
4 Evaporation, evapotranspiration and soil moisture  [2008] 561 Ko
5 Surface water quantity and sediment measurement  [2008] 415 Ko
6 Groundwater  [2008] 855 Ko
7 Water quality and aquatic ecosystems  [2008] 194 Ko
8 Safety considerations in hydrometry  [2008] 92 Ko
9 Data processing and quality control  [2008] 216 Ko
10 Data storage, access and dissemination  [2008] 324 Ko  

Volume II: Management of Water Resources and Application of Hydrological Practices

Chapters, TitleDownloadable PDFPrevious version
1 Introduction [2009] 67 Ko
2 Hydrological Services [2009] 93 Ko
3 Integrated water resources management [2009] 270 Ko
4 Applications to water management [2009] 5815 Ko
5 Extreme value analysis [2009] 832 Ko
6 Modelling of hydrological systems [2009] 1210 Ko
7 Hydrological forecasting [2009] 4726 Ko
Guide to all of our downloads.

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