Guide to Hydrological Practices, 6th edition, Volume I - Hydrology.nl

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GUIDE TO HYDROLOGICAL PRACTICES
Page
5.3.6 Measurement of discharge under difficult conditions ............................................ I.5-13
5.3.7 Non-traditional methods of stream gauging ......................................................... I.5-16
5.4 Stream-gauging stations ........................................................................................................ I.5-20
5.4.1 Purpose of stream-gauging stations ...................................................................... I.5-20
5.4.2 Selection of site .................................................................................................... I.5-21
5.4.3 Stage-discharge controls ....................................................................................... I.5-21
5.4.4 Measuring structures ............................................................................................ I.5-21
5.4.5 Stage-discharge relationships ................................................................................ I.5-23
5.4.6 Computation of mean gauge height of a discharge measurement ........................ I.5-24
5.5 Sediment discharge and yield ................................................................................................ I.5-24
5.5.1 General ................................................................................................................ I.5-24
5.5.2 Selection of site .................................................................................................... I.5-25
5.5.3 Measurement of suspended-sediment discharge ................................................... I.5-25
5.5.4 Measurement of bed-material discharge ............................................................... I.5-27
References and further reading .......................................................................................................... I.5-28
CHAPTER 6. GROUNDWATER ..........................................................................................................
6.1 General ............................................................................................................................. I.6-1
6.2 Occurrence of groundwater .................................................................................................. I.6-1
6.2.1 Water-bearing geological units ............................................................................. I.6-1
6.2.2 Development of a hydrogeologic framework ........................................................ I.6-2
6.3 Observation wells .................................................................................................................. I.6-5
6.3.1 Installation of observation wells ............................................................................ I.6-5
6.3.2 Testing of observation wells .................................................................................. I.6-11
6.3.3 Sealing and filling of abandoned wells .................................................................. I.6-11
6.4 Groundwater-level measurements and observation well networks ......................................... I.6-11
6.4.1 Instruments and methods of observation .............................................................. I.6-11
6.5 Aquifer and confining-bed hydraulic properties ..................................................................... I.6-18
6.5.1 Hydraulic parameters ............................................................................................ I.6-18
6.5.2 Overview of common field methods to determine hydraulic parameters ............... I.6-20
6.6 Recharge and discharge, sources and sinks in a groundwater system ..................................... I.6-21
6.6.1 Recharge from precipitation ................................................................................. I.6-22
6.6.2 Groundwater–surface water relationships ............................................................. I.6-22
6.6.3 Well pumpage ...................................................................................................... I.6-23
6.7 Use of data in groundwater models ....................................................................................... I.6-23
6.8 Remote-sensing ..................................................................................................................... I.6-23
References and further reading .......................................................................................................... I.6-24
I.6-1
CHAPTER 7. WATER QUALITY AND AQUATIC ECOSYSTEMS ..........................................................
7.1 General ............................................................................................................................. I.7-1
7.2 Specific requirements for water-quality monitoring ............................................................... I.7-1
7.2.1 Water-quality parameters ...................................................................................... I.7-1
7.2.2 Surface-water quality ............................................................................................ I.7-1
7.2.3 Precipitation quality .............................................................................................. I.7-3
7.2.4 Groundwater quality ............................................................................................. I.7-4
7.2.5 Sediment quality .................................................................................................. I.7-5
7.3 Sampling methods ................................................................................................................ I.7-5
7.3.1 Types of water samples ......................................................................................... I.7-6
7.3.2 Collecting a representative water sample .............................................................. I.7-6
7.3.3 Sampling for the analysis of water stable isotopes ................................................. I.7-6
7.3.4 Radioactivity measurement ................................................................................... I.7-7
7.3.5 Field sampling equipment and techniques ............................................................. I.7-7
I.7-1