Water Use Trends &
Forecasting
Lecture 1
Dr. Jawad Al-rifai
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Water supply
Water supply is one of balancing
Availability & demands.
Availability means:
Quality of resources
Depletion & Replenishment
Demands (current & Future)
Domestic Use
Industrial Activity
Commercial
Ecology & Economic conditions
Technical & Social factors
Decisions on designing of water distribution
system and treatment plant should rely on the
above factors.
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Water use sectors are:
◦ Agriculture (critical in arid and semiarid
regions- up to100%)
◦ Thermoelectric power (plant size & cooling heat
transfer efficiency)
◦ Cities & Communities (drinking, cooking, showering,
lawn watering, pool, street cleaning, fire freighting, etc)
◦ Industry & Commercial activities (Recycling and
Process changes)
◦ Natural Systems
◦ Recreation
◦ Energy Resource Development
When water supplies are limited, conflicts
among users become intense and tradeoffs
must be made
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Factors Affecting Water Use
Population
 Climate
 Types of water uses (industrial, commercial,
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agriculture, etc)
Economic conditions
 Conservation (water saving)
 Management practices (including reuse of
wastewater & storm water)
 Tourism
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Average day demand. The total annual quantity of water production for
an agency or municipality divided by 365.
Maximum day demand. The highest water demand of the year during
any 24-h period.
Peak hour demand. The highest water demand of the year during any
1-h period.
Peaking factors. The increase above average annual demand,
experienced during a specified time period. Peaking factors are
customarily used as multipliers of average day demand to express
maximum day and peak hour demands.
Distribution pipeline or main. A smaller diameter water distribution
pipeline that serves a relatively small area. Water services to individual
consumers are normally placed on distribution pipelines. Distribution
system pipelines are normally between 150 and 400 mm (6-16 in.).
Transmission pipeline or main. A larger-diameter pipeline, designed to
transport larger quantities of water during peak demand-periods. Water
services for small individual consumers are normally not placed on
transmission pipelines. Transmission mains are normally pipelines larger
than 400 mm (16 in.).
Definitions
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Fluctuation of daily water use patters
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