Civil Engineering Association

Computer Systems and Water Resources (Developments in Water Science)

PREFACE
We should like to state from the outset what this book is not. It is not a study of water resource systems or of methodologies for the planning, design, and:operation of such systems-topics that are treated in a vast body of excellent. books, papers, and reports which have appeared in recent years. Rather, the book addresses itself to an area in water resources technology that has received practically no attention in the literature: the description
and assessment of the pervasive role that computer systems have come to exert in this field, and are likely to exert in the future. While there are few practitioners or researchers in water resources today who have not used a computer in their work, and derived opinions, preferences, and a feeling for the possible directions of future evolution concerning computer systems, it is
fair to say that a systematic and comprehensive discussion of the subject has been lacking. Though this book does not provide such a comprehensive discussion, it does offer a state of the art overview of some of the principal considerations concerning computer systems that the decision-maker and practitioner in water resources can no longer afford to neglect. Since we
believe that an historical perspective is important, in several sections of the book we have provided brief sketches of the early use of computers in a number of water resource areas.

The germ of the book was a study carried out for the U.S. Office of Water Resources Research' , which was subsequently expanded, modified, and brought up to date. The study could not have been accomplished without the expertise of numerous persons. In addition to Robert Cheever who was a participant in the original study, numerous persons have contributed their expertise and advice. Personal communications with M. Abbott, E.
Altouney, P. Caruso, P. Combs, A. Cosper, N.H. Crawford, B. Doyle, A.J. Frederick, C. Furgeson, S. Lang, H.L. Longford, L. Manning, R. Myrick, J. Orlob, R.V. Thomann, and D.W. Webber, to name only a few, provided valuable direction and insight into the important, but often subtle problems encountered in the establishment of computer and programming policy.
Contributions by Sheri Gunther and Brandy Rommel (Editing), Vivian 1 Bugliarello, G. and Gunther, F.J., Computers and Water Resources, U.S. Office of Water Resources Research, 1973.
Cardwell (Administration), Myra Martin (Typing), and Edward Daniels (Drafting), in dealing with the practical aspects of generating this document cannot be fully acknowledged.


CONTENTS
PREFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
..
LIST OF ABBREVIATIONS . . . . . . . . . . . . . . . . . . . . . . . vii
I INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
The Growth of Computers . . . . . . . . . . . . . . . . . . . . . 4
. . . . . . . . . . . . .4
Analog and Hybrid Computers . . . . . . . . . . . . . . . . . 7
Computer Users . . . . . . . . . . . . . . . . . . . . . . . . . 10
Governmental Organizations . . . . . . . . . . . . . . . . . 10
Private Organizations . . . . . . . . . . . . . . . . . . . . . . 12
Independent Organizations . . . . . . . . . . . . . . . . . . 14
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Digital Computers and Minicomputers
II THE ELEMENTS OF A COMPUTER SYSTEM . . . . . . . . . . . 16
Computer Hardware . . . . . . . . . . . . . . . . . . . . . . . 16
Digital Computers . . . . . . . . . . . . . . . . . . . . . . 16
Processor . . . . . . . . . . . . . . . . . . . . . . . . . 18
Memory . . . . . . . . . . . . . . . . . . . . . . . . . 20
Input/Output . . . . . . . . . . . . . . . . . . . . . . 21
Minicomputers . . . . . . . . . . . . . . . . . . . . . . . . 21
Analog Computers . . . . . . . . . . . . . . . . . . . . . . 23
Hybrid Computers . . . . . . . . . . . . . . . . . . . . . . 25
Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Hardware Considerations . . . . . . . . . . . . . . . . . . . 27
The Man-Machine Interface . . . . . . . . . . . . . . . 27
Computer-Instrument Packages . . . . . . . . . . . . . 27
Maintenance . . . . . . . . . . . . . . . . . . . . . . . 30
Hardware Decisions . . . . . . . . . . . . . . . . . . . 30
What Kind and Size Computer . . . . . . . . . . . . . . 31
Purchase. Rent. or Build . . . . . . . . . . . . . . . . . . 31
Financial Considerations . . . . . . . . . . . . . . . . . 35
Time-sharing . . . . . . . . . . . . . . . . . . . . . . . 35
Up-grading a Facility . . . . . . . . . . . . . . . . . . . 36
Computer Software . . . . . . . . . . . . . . . . . . . . . . . 37
Digital and Analog Programming . . . . . . . . . . . . . . . 38
Hybrid Programming . . . . . . . . . . . . . . . . . . . . . 39
Software Engineering and Management . . . . . . . . . . . 40
Software/Hardware Compatibility . . . . . . . . . . . . . . 43
. . . . . . . . . . . . . . . 44
Processing Modes . . . . . . . . . . . . . . . . . . . . . . . . . 45
Real Time Processing . . . . . . . . . . . . . . . . . . . . . 45
Non-Real Time Processing . . . . . . . . . . . . . . . . . . 46
Batch Processing . . . . . . . . . . . . . . . . . . . . . . . . . 46
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Software Protection and Pricing
111 SOFTWARE AND HARDWARE SYSTEMS
FOR WATER RESOURCES . . . . . . . . . . . . . . . . . . . . . 49
Software Systems . . . . . . . . . . . . . . . . . . . . . . . . 54
Problem-Oriented Languages . . . . . . . . . . . . . . . . . 54
Evolution . . . . . . . . . . . . . . . . . . . . . . . . 56
HYDRO . . . . . . . . . . . . . . . . . . . . . . . . . 57
HYDRALGOL . . . . . . . . . . . . . . . . . . . . . . 61
FORTRAN-HYDRO . . . . . . . . . . . . . . . . . . . 66
Other Developments . . . . . . . . . . . . . . . . . . . 66
Modularity Concepts . . . . . . . . . . . . . . . . . . . . . 68
Program Libraries . . . . . . . . . . . . . . . . . . . . . . 70
The ASCE Study . . . . . . . . . . . . . . . . . . . . . 72
Examples of Program Libraries . . . . . . . . . . . . . . 75
Standardization and Documentation . . . . . . . . . . . . . 77
Hardware Systems . . . . . . . . . . . . . . . . . . . . . . . . 78
Centralized Data Systems . . . . . . . . . . . . . . . . . . 78
Central Data Bank Communications . . . . . . . . . . . . . 84
Other Communications Systems . . . . . . . . . . . . . . . 86
The Role of the Minicomputer . . . . . . . . . . . . . . . . 86
Other Centralized Activities . . . . . . . . . . . . . . . . . 88
Program Libraries in the Central System . . . . . . . . . . . 88
Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
IV COMPUTER UTILIZATION AREAS . . . . . . . . . . . . . . . . . 93
Data Acquisition and Management . . . . . . . . . . . . . . . . 93
The Water Resources Division-USGS . . . . . . . . . . . . 9 3
NAWDEX . . . . . . . . . . . . . . . . . . . . . . . . . . 95
STORET-EPA . . . . . . . . . . . . . . . . . . . . . . . . 95
Satellite Data . . . . . . . . . . . . . . . . . . . . . . . . . 97
DataTechnology . . . . . . . . . . . . . . . . . . . . . . . 98
Analysis and Design . . . . . . . . . . . . . . . . . . . . . . 101
Process Control . . . . . . . . . . . . . . . . . . . . . . . . 102
The Elements of a Process Control System . . . . . . . . . 105
Analog Computer Process Control . . . . . . . . . . . . . 106
Digital Computer Process Control . . . . . . . . . . . . . 106
References . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
V COMPUTERS IN SURFACE WATER SYSTEMS . . . . . . . . . 109
Historical Notes . . . . . . . . . . . . . . . . . . . . . . . . 110
Data Acquisition and Management . . . . . . . . . . . . . . . 115
Water Quality Monitoring . . . . . . . . . . . . . . . . . 115
Flood Control Data . . . . . . . . . . . . . . . . . . . . 116
Adjusting Records . . . . . . . . . . . . . . . . . . . . . 117
Analysis and Design . . . . . . . . . . . . . . . . . . . . . . 117
Dynamic Programming and Monte Carlo Methods . . . . . 118
Dynamic Programming for Multiple Structures . . . . . . 118
Hybrid System-Flood Studies . . . . . . . . . . . . . . . 120
Digital Watershed Simulation . . . . . . . . . . . . . . . 120
Thermal Pollution Simulation . . . . . . . . . . . . . . . 121
Lake Modeling . . . . . . . . . . . . . . . . . . . . . . . 123
Optimal Control Theory-Aeration . . . . . . . . . . . . 126
Total Water Resource Management-Simulation . . . . . . 127
Process Control . . . . . . . . . . . . . . . . . . . . . . . . 130
Control and Monitoring-Rivers . . . . . . . . . . . . . . 130
The California Aqueduct . . . . . . . . . . . . . . . . . . 131
References . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
VI COMPUTERS IN GROUNDWATER SYSTEMS . . . . . . . . . . 135
Historical Notes . . . . . . . . . . . . . . . . . . . . . . . . 136
Analysis and Design . . . . . . . . . . . . . . . . . . . . . . 139
The Relaxation Method . . . . . . . . . . . . . . . . . . 139
The Finite Difference Method . . . . . . . . . . . . . . . 140
The Finite Element Method . . . . . . . . . . . . . . . . 141
Basin Studies . . . . . . . . . . . . . . . . . . . . . . . . 142
Groundwater Flow-Hybrid Applications . . . . . . . . . 142
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
VII COMPUTERS IN WATER UTILIZATION SYSTEMS . . . . . . . 146
Historical Notes . . . . . . . . . . . . . . . . . . . . . . . . 146
Analysis and Design . . . . . . . . . . . . . . . . . . . . . . 150
Distribution Systems . . . . . . . . . . . . . . . ; . . . . 150
Waste Water Collection . . . . . . . . . . . . . . . . . . . 151
Treatment Plant Design . . . . . . . . . . . . . . . . . . . 152
andinstreams . . . . . . . . . . . . . . . . . . . . . 153
Irrigation 1 5x4
Process Control . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Urban Water Supply' . . . . . . . . . . . . . . . . . . . . 155
Operation of Distribution Systems . . . . . . . . . . . . . 156
Water Treatment-The Chicago Filtration Plant . . . . . . 158
Sewerage Treatment Plants . . . . . . . . . . . . . . . . . 159
References . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Biological Processes in Water Treatment Plants
. . . . . . . . . . . . . . . . . . . . . . . . .
Vlll LOOKING TO THE FUTURE . . . . . . . . . . . . . . . . . . 162
Computer Areas . . . . . . . . . . . . . . . . . . . . . . . . 162
Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Software . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Methodology . . . . . . . . . . . . . . . . . . . . . . . . 165
Application Areas . . . . . . . . . . . . . . . . . . . . . . . 165
Data Acquisition and Management . . . . . . . . . . . . . 165
Analysis and Design . . . . . . . . . . . . . . . . . . . . 166
Process Control . . . . . . . . . . . . . . . . . . . . . . 167
The Overall Issue . . . . . . . . . . . . . . . . . . . . . . . . 168
The Structure of the Interface Between Computer Systems
and Water Resources Technology . . . . . . . . . . . . . . . 169
References . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
APPENDICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200