1

CHAPTER I

INTRODUCTION

The sustainable water supply in northern China is unable to meet the current demands of

agricultural, industrial and municipal uses. This situation is the result of a very limited

natural supply combined with a large and growing population. While the area has been

water short for many years the rapid changes since the reforms of 1978, including

urbanization, modernization and economic growth, have greatly aggravated the situation.

Central government priorities over the past 50 years have also added to the problem.

State spending has concentrated on increasing industrial output at the expense of

spending on urban infrastructure and improving agricultural production methods.

Irrigation is by far the largest user and consumer of water in the region. Outdated

irrigation techniques and water losses in the distribution system account for a large

proportion of water use. A growing population and a demand for a more varied diet are

putting greater demands on water for irrigation. An economy that’s reliant on heavy

industry, with many plants using outdated industrial methods, also contributes to high

water use. Water pollution, caused by untreated municipal and industrial wastewater and

agricultural run off, further limits the supply of water available for human consumption

and irrigation. Current state policies put the emphasis on a growing economy with, as

yet, little regard for enforcing environmental protection policies.

The water shortage and pollution problem is one that can only be solved by a regional

planning approach, yet there is little regional planning or coordination in China now,

jurisdictions are more likely to compete with each other to attract investment.

Among the 120 largest cities in the world Beijing is the most water deficient (Hong-rui

and Yan 1998). As well as Beijing, the capital city region includes Tianjin, an industrial

port city on the Bay of Bohai and seven other major cities in Hebei province, for a total

population of 58 million and an urban population of 18 million. By government policy

the urban population in China was relatively stable before the reforms but it has been

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growing rapidly since 1984. From 1980 to 1990 the non-agricultural populations of

Beijing and Tianjin both grew by 24%. From 1990 to 1997 the growth was slower, with

11% for Beijing and 6% for Tianjin. On the other hand, among the seven other major

cities the non-agricultural population grew by 30% from 1990 to 1997 (Project database

1999). The official population of the metropolitan area of Beijing is approximately 11

million and is expected to grow by one million over the next five years. These figures do

not include the unofficial “floater” population, currently estimated at three million. The

move to the city puts greater demand on water resources as urban residents traditionally

use more water per capita than do rural residents. Within the cities modernization is also

increasing per capita water use as traditional courtyard houses with no facilities are being

replaced by new apartments with all the modern water using conveniences.

Urbanization, modernization, a demand for a more varied diet, poorly maintained

infrastructure, an economic structure still dependent on heavy industry, an economic

policy that focuses on growth with little regard for the environment and little regional

planning all contribute to the current water crisis.

Under the umbrella of the Canadian government’s Country Development Policy

Framework for China, the presidents of six major Chinese and Canadian Universities met

to create the “ 3 X 3” university partnership in 1994. One of the working groups within

this partnership focused on environmental management. After several meetings of

faculty from the six universities the environmental management group decided to study

water management for sustainable development in the Beijing-Tianjin region. In 1997 the

project got funding approval under the CIDA-funded Canada-China Higher Education

Program. The overall objectives of the project are policy recommendations and the

enhancement of human resource capacity. The themes of the project were determined

and divided among pairs of universities as follows:

Water supply, pricing and technological approaches to water management -- University

of Toronto and Tsinghua University.

Water demand estimation -- McGill University and Nankai University.

Environmental impact analysis -- Université de Montréal and Peking University.

3

Policy and institutional framework -- University of British Columbia (UBC) and Peking

University. A paper on the institutional framework of water resource management in the

capital city region was prepared by EVS Environment Consultants for UBC in 1997.

After examining the roles of the various government agencies involved in water resource

management, the consultants concluded that the overlapping duties and responsibilities

and lack of coordination among the agencies had considerably aggravated the water

resource problem in the region (EVS Environment Consultants 1997).

The objective of this paper is to suggest an approach to forecasting water demand in the

region. The approach will be based primarily on a model developed by Environment

Canada and take into consideration the forecasting work that has already been done in

this region of China. Because the scope of the project is huge, the data limited and

economic and social changes rapid, forecast accuracy is not to be expected. The

objective of the modeling exercise is to roughly quantify the water deficit that will occur

if current water use trends continue and no action is taken, and then to judge the impact

of various water management options on reducing this deficit. The results of the

modeling exercise can then be used in the formation of water use policy. Pricing is a

crucial policy option that is currently being used in a very limited way. However, the

concepts of price and the economic value of water for various uses will not be explored in

this paper, as they are being considered in depth as another theme within the overall

project. The objective is to set out a water demand estimation framework and list the

water saving options that can be explored, not to examine each option in detail.

The paper begins with a brief overview of the supply and importance of water at the

world level, with a brief discussion of water management concepts. The water shortage

situation in the capital city region in China is then presented and the trends that have

aggravated the shortage and some of the impacts of the shortage are discussed. A review

of the basics of water demand estimation and forecasting are presented in Chapter IV,

along with a brief description of two comprehensive models, MAIN II developed in the

U.S. and WUAM developed in Canada. Chapter V presents an overview of the suggested

water demand estimation model and a number of key water saving options that should be

4

explored. Finally, a sample water demand estimation model for the city of Tianjin is

presented, with comparisons provided of other estimates and the water supply of that city.

Some of the figures quoted throughout the paper refer to “Project database 1999”. This

is the database that was created for McGill’s part of the 3X3 project.

5

CHAPTER II

GLOBAL FRESHWATER RESOURCES

A basic necessity

Taken in total, the planet’s total freshwater supply is sufficient for now and for many

years to come. However this total supply is not evenly distributed among the world’s

population and is not evenly distributed throughout the year. In areas of the world like

Canada, where the per capita availability of water is very high, a constant, clean and

unlimited supply of water is taken for granted. But in much of the world, limited and

polluted water supplies inhibit development, endanger health and influence international

relations.

Water is a renewable resource, it is not consumed but rather recycled through the

hydrological cycle and returned for reuse. However, the hydrological cycle does not

guarantee a constant supply. Water is lost to the cycle due to pollution, of both surface

and ground water supplies. Water percolating from agricultural fields into ground water

supplies can only be reused so many times before the concentration of soil salts render it

a pollutant. Water can also be used at an unsustainable rate, where it is withdrawn from

surface and/or groundwater sources at a faster rate than can be replenished by the

hydrological cycle.

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Figure 2.1 The Hydrological Cycle

Source: Figure 10 p. 335 in Henry J. and Heinke G. (1989)

Water is a basic requirement for our survival. At a minimum each person requires

anywhere from 20 to 40 liters of freshwater per day to meet basic drinking and sanitation

needs. If bathing and cooking are included these minimums can increase to 200 liters per

day. Beyond these personal requirements, water is also needed for food production and

economic development. Of the world’s total water demands, agriculture accounts for

69%, industry for 23% and domestic use for 8% (Hinrichsen D. et al 1998). The amount

of water that is actually used by any one country is dependent on it’s availability and on

the country’s level of economic development. Developed countries use much more water

per capita than do developing countries. In Africa per capita water use is estimated at 47

liters per day compared to 578 liters in the US. Throughout the world per capita water

demand is growing as populations increase, demand for irrigated agriculture increases

7

and economic development occurs. The World Bank warns that lack of fresh water will

likely be one of the main inhibiting factors to economic development in upcoming

decades.

According to Ralph Daley, a researcher at the International Network of Water,

Environment and Health at McMaster University, water shortages will also become a

catalyst to international conflicts. Nearly one half of the world’s surface is covered by

river basins that are shared by two or more countries. As water levels drop international

conflicts will likely result. Tensions already exist. While both Jordan and Israel get

water from the Jordan River, Israel controls the distribution. The government of Israel

recently announced that is was reducing the flow to Jordan by 40%. Before his death,

King Hussein of Jordan said that the water issue could cause a war (The Montreal

Gazette 4 May 1999). Egypt depends on the Nile for 98% of its water needs yet the bulk

of the Nile’s water, 85%, comes from Ethiopia, a country expecting to double its

population in 20 years. As it develops Ethiopia will require more and more of the Nile’s

water. How will downstream users like Egypt and the Sudan meet their water needs?

(Paul Simon The Montreal Gazette 13 April 1999).

It is not only limited supply that is a concern, polluted water takes a serious toll on human

life and the natural environment. Worldwide, water that has been polluted by human,

animal or chemical wastes is responsible for over 12 million deaths per year. A further

2.3 million people live with diseases linked to polluted water (Hinrichsen et al. 1998).

According to the UN, 80% of deaths in developing countries are caused by unsafe water,

resulting in over 5.3 million deaths per year (The Montreal Gazette 4 May 1999).

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Figure 2.2 The population-freshwater dynamic

Source: Figure 1. p. 2 in Hinrichsen et al. (1998)

Hydrologists define water scarcity as an annual renewable fresh water supply of less than

1000 cubic meters per person. Countries with water scarcity will experience chronic and

widespread shortages that hinder development. Water stress is defined by a renewable

fresh water supply of between 1,000 and 1,700 cubic meters per person. Countries with

water stress will face temporary or limited water shortages. Among the countries of the

world, 31, representing 8% of the world’s population, are facing chronic water shortages,

either stress or scarcity. It is projected that by the year 2025 this figure will have risen to

48 countries and 35% of the world’s population (Hinrichsen D. et al 1998).

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Figure 2.3 Countries with Water Scarcity and Water Stress – 2025 Projections

Source: Adapted from Figure 5 p.8 in Hinrichsen D. et al. (1998)

Water management basics

Slowing population growth, water conservation and improved water management

strategies can help avoid a crisis in those areas facing water stress and scarcity. For the

most part current management practices are not working. Ismail Serageldin (1995), Vice

President for Environmentally Sustainable Development at the World Bank lists the

following four main weaknesses in current water management practices:

• Fragmented responsibility and no coordination of policies between economic sectors.

Water quality and issues of health fall through the cracks in the bureaucracy because

they don’t fit within any one government agency’s mandate.

• Development, operation and maintenance of water systems is under central control.

These agencies are often over taxed and lack the necessary technical expertise. Input

from water users and community participation are not included when making policies

and regulating water use therefore projects often don’t meet users needs.

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• Water is undervalued.

Water prices generally are too low and often large water users, like farmers, are given

water subsidies; both practices encourage wasting water.

• The importance of water to human and environmental health is not reflected in water

management policies.

Water is typically considered a natural resource that should be equally available for

all uses. Instead, the users of water should be prioritized and the quality of water

protected.

Within each country different regions compete for the same limited resource. As well,

different sectors of the economy, from agriculture to industry, depend on reliable water

sources. Therefore, water short countries have to approach water management in a

comprehensive manner, water use has to be prioritized and rationalized to ensure health

and economic growth for current and future generations. “Reform in water resources

management is a political task, which means it requires a political will from decision

makers to prioritize the interests of the government (state). For instance, it must

determine how important water resources protection is to the government comparing to

economic growth.” (EVS Environment Consultants 1997, 32). Comprehensive

management has a geographic component as well. Management of water at the

watershed or river basin level is necessary to avoid conflicts between the water demands

of separate jurisdictions. This level encompasses the land area served by all the rivers

and aquifers that are drained by a river system or major tributary. Water demand

forecasting is one of the most important elements of comprehensive water resources

planning and management.

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CHAPTER III

THE WATER SHORTGAE IN CHINA’S CAPITAL CITY REGION

Description

Table 3.1. shows the water resources of selected countries. China as a whole is relatively short of water.

The uneven distribution of water and population in the country leaves Northern China extremely short of

water.

Table 3.1. Water Resources by Country

(in cubic meters) Water perAnnual land area

renewable (per square WaterCountry resources kilometer) per capita

Canada 2,901 290,944 98,462Brazil 6,950 816,494 42,957Russian Federation 4,498 263,426 30,599United States 2,478 264,659 9,413China 2,812 292,917 2,292 Northern China 405 150,528 750 Southern China 2,278 654,532 3,440India 2,085 700,840 2,228World 41,022 301,988 7,176

Source: WRI 1996; SSB 1996 in World Bank B 1998.

China’s capital city region is within Northern China, it is comprised of Beijing, Tianjin

and seven metropolitan areas in Hebei province; Tangshan, Qinhaugdao, Chengde,

Zhangjiakou, Boading, Langfang and Cangzhou. In 1997 the total population of these

metropolitan areas was over 57 million, 18 million, or 31%, were in urban areas.

Population (in millions)

Metropolitan Areas Total UrbanBeijing 10.86 7.44Tianjin 8.98 4.93Cities in Hebei 37.69 5.32Total 57.53 17.69

Source: Project database 1999

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The capital city region is also within the Hai river basin. This basin is one of the nine

major basins in China and one of the four northern basins. It covers an area of 318,161

square kilometers.Figure 3.1. Hai River basin

Source: Figure IV-1. Hufschmidt et al. (1987)

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The Hai river basin is at times also referred to as the Hai He-Luan He basin. It’s short of

water both in terms of its population and land. It represents 1.5 percent of China’s

surface water resources but 10 per cent of the population and 11 per cent of the cultivated

land. Per capita run-off in the basin is 355 cubic meters per year compared to 2,292 for

all of China (World Bank B 1998). There are 3,760 cubic meters of water for each

hectare of land in the Hai basin compared to 28,000 for China as a whole (ESCAP 1997).Figure 3.2. Major river systems

Source: Adapted from irrigation and Drainage in China, Ministry of Water Resources and Electric Power,

1987, in ESCAP 1997, Figure 3

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Table 3.3. Water resources in China

Per capitaRegion Share (cubic meters) Cultivated land Population

% % %Total 100.0 2,292 100.0 100.01. Northeastern rivers 6.9 1,625 19.8 9.82. Hai River 1.5 355 10.9 9.83. Huai/Shangdong rivers 3.4 515 14.9 15.44. Yellow River 2.6 749 12.7 8.25. Yangtze River 34.2 2,280 24.0 34.86. Southern rivers 16.8 3,534 6.8 11.07. Southeastern rivers 9.2 2,892 3.4 7.48. Southwestern rivers 20.8 32,216 1.7 1.59. Inland rivers 4.6 5,126 5.8 2.1

Source: Wu 1989. From World Bank B 1998.Note: These data were compiled in the early 1980s. It is assumed that the relative values forwater supply and cultivated land have not changed. The 1995 population was used as the basefor per capita water resource calculations.

To alleviate the water shortage problem the government authorized the building of

another “Grand Canal” in 1995 to bring water from the Danjiangkou Reservoir in central

China to Beijing. While, if constructed, this canal could increase surface supply to the

Hai basin by 20 billion cubic it will not solve the water shortage problem for long (World

Bank A 1998).Table 3.4. Renewable water resources

(billions of cubic meters)

mean annual Water volume TotalRegion Surface run-off Groundwater deducted* water resourcesTotal 2,711.5 828.8 727.9 2,812.4Northern China 334.3 522.6 97.9 405.4 Hai River Basin 28.8 26.5 13.2 42.1Southern China 2260.8 573.7 557.8 2276.6Inland rivers 116.4 86.2 72.2 130.4

* to provide renewable ground water estimates.Source: ESCAP 1997

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20005%

31%

58%

6%

DomesticIndustrialIrrigationRural

Total water resources for the basin are estimated at 42.1 billion cubic meters. Demand in

the basin is estimated at 61.9 billion cubic meters for 2000, leaving a shortage of just

under 20 billion cubic meters. Demand is currently being met by the overexploitation of

underground water supplies.

Table 3.5. Existing water use and projections - World Bank

( in billions of cubic meters)

Domestic Industry Irrigation Rural TotalRegion 1980 2000 1980 2000 1980 2000 1980 2000 1980 2000

Total 6.8 29.4 45.7 177.3 365.6 506.4 25.6 51.7 443.7 764.8Northern China 3.2 11.1 17.9 69.3 132.2 171.7 9.5 22.0 162.8 274.1 Hai River Basin1.1 3.0 4.9 19.0 30.9 36.2 1.5 3.7 38.4 61.9Southern China 3.4 17.8 27.1 105.3 180.2 272.4 14.4 27.1 225.1 422.6Inland rivers 0.2 0.5 0.7 2.7 53.2 62.3 1.7 2.6 55.8 68.1

Note: Data for 2000 are projections.Source: Wu 1989; World Bank staff estimates in Clear Water, Blue Skies: China’s Environment inthe New Century 1998.

Table 3.5 shows estimated demand by water using sector. The following chart presents

the same information for the Hai River basin, showing the relative size of each water

using sector and how it is expected to change. Note the increase in the proportion of

industrial water use, from 13% of total in 1980 to 31% in 2000.

19803%

13%

80%

4%

Source:Adapted from Wu 1989;World Bank staff estimates in Clear Water,Blue Skies:China's Environment

in the New Century 1998.

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Trends that affect the shortage

With urbanization, modernization and the expansion of industrial and agricultural

development that began in the late 1970s, water shortages in Northern China have

become increasingly serious. Shortages caused by increased demand are further

aggravated by water loss due to inefficiencies and leakage.

Urbanization and modernization

After being held in check by government policy until 1978, the flow of people from rural

areas to cities has grown dramatically. Estimates put the urban population at 20% in

1980, a figure that is expected to increase to 34% by the year 2000 (World Bank A 1998).

Official population statistics for urban areas do not include the large number of “floaters”

who come from the countryside to work, but are not official residents of the city and have

no claim on services, including housing. Most live in squatter settlements in the suburbs.

While the official urban population of Beijing is approximately 7 million the floater

population may be as large as 3 million. Informal residential areas continue to grow

around the periphery of Beijing. The urban population of the Hai river basin has been

projected to increase by 45%, from 29 million in 1993 to 42 million by 2000 (ESCAP

1997).

This move to the city has been reflected in a building boom in China’s major cities.

“Between 1982 and 1990, 83.57 million square meters of new buildings were built

throughout Beijing Municipality – nearly as much as had been built during the previous

32 years” (Beijing Master Plan 1993, 88). In Tianjin even greater growth was seen.

From 1980 to 1995, 58.41 million square meters of new building space were constructed,

compared to 5.15 million square meters from 1950 to 1980. New housing space

increased from 1.82 million square meters from 1950 to 1980 to 35.63 million square

meters from 1980 to 1995 (Tianjin Statistical Yearbook 1996). Traditional courtyard

houses within the inner city, most without basic sanitary facilities and services, are being

17

replaced by new developments with all the modern conveniences. Incomes have doubled

since the start of economic reforms, which has increased demand for the material perks of

modern living. Increases in demand are further aggravated by losses in the supply

network. Close to 43% of potable water generated in Beijing is unaccounted for. This

loss is caused by leaky pipes, leaking faucets, unmonitored water use and poor

accounting practices (Project proposal 1997).

Water demand per capita increases with urbanization. “Historically, as customers are

drawn within centralized supply systems, acquiring the full complement of bathrooms,

kitchen, and laundering facilities, not to mention a lifestyle of expansive lawns, gardens,

and landscaping, per capita water use increases” (Jones et al 1984, 38). Expanded uses

also include public uses like fire fighting, street cleaning, water for public gardens, parks

and for servicing public buildings and for water to transport and treat human waste.

Commercial buildings, office buildings and municipal facilities account for a large

proportion of a city’s water use. Most have flush toilets and some have bathing facilities.

Per person water use in these public buildings tends to be higher than for home use. A

growing component of urban use are hotels and restaurants. They are large water users

and are becoming an important part of the urban economy, especially in Beijing where

the government is encouraging tourism (Hufshmidt et al 1987). The average per capita

water consumption in Beijing is 145 litres per day. For high quality apartments the figure

is 300 to 450 litres and for luxury hotels it can be as high as 2000 litres per day (Liu C.

and Xie M. 1981).

Agricultural output

With a growing population and changes in tastes, demand for grain is increasing, both for

direct consumption and for livestock. “China needs to increase its annual food production

from 400 to 500 million tons by the year 2000.” (ESCAP 1995, 29) To meet grain needs

land under irrigation will have to increase, including the land within the Hai basin

(ESCAP 1997). Projections made by the Ministry of Water Resources from 1993 to 2000

show an expected increase in the area under irrigation from 50.0 million hectares to 53.3

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million hectares, with most of the new irrigation area to come from the Huai He Basin,

the Chang Jiang Basin, the Hai He Basin and the interior basins (ESCAP 1997).

Irrigation is the largest user of water in China, the proportion of total water used by

irrigation in the Hai basin was 80% in 1980 and is forecast to be 58% by 2000 (Table

3.5).. However, there is also evidence that the amount of land that is dedicated to

agriculture is decreasing in some areas due to development. This puts even more

pressure on the land that remains, increasing productivity per hectare usually means a

greater reliance on irrigation and fertilizer. However, current irrigation methods are very

inefficient, “it is clear that as much as 50 per cent of the water diverted from the rivers for

irrigation of the fields could be lost in various forms” (ESCAP 1989, 21).

Importing larger amounts of grain to meet the increases in demand doesn’t seem to be an

option. According to the government’s Ninth Five-Year Plan and the Fifteen-Year

Perspective Plan “ the Chinese authorities are determined to avoid heavy dependence on

imported grain. They fear that imports could be disrupted by uncertainty and volatility in

world markets, and the possibility of trade friction with large grain exporters” (World

Bank A 1998, 61).

Growing industrial sector

Throughout the 1990s, industrial output in China grew by 15% per year. The Chinese

economy is currently ranked anywhere from 3rd to 7th in the world and is expected to be

number 1 by 2010 (Halweil 1998). Many of the industrial mainstays of the economy are

heavy water users. The Beijing –Tianjin - Tangshan industrial base is one of China’s

main producers of iron and steel, petrochemicals, marine chemicals, fuel, power, and

machinery. In Beijing and Tianjin industrial output increased by 180 percent and 160 per

cent respectively, from 1978 to 1984 (ESCAP 1997).

The government is still the largest player in the Chinese economy. Two thirds of China’s

primary and secondary industries are state owned and operated (State Owned Enterprises

or SOEs), mostly by provincial or municipal governments. Many state owned industries

are operating inefficiently and unprofitably, they use outdated technologies and methods

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that waste and pollute water. China’s paper, steel and other major water using industries

are estimated to use five to ten times the amount of water per output as their counterparts

in developed countries (Tseng 1997). On the positive side for water use, the government

has recently started closing down some SOEs.

Industrial growth until the reforms of 1978 was concentrated in the cities. In the past 20

years there has been a growth of town and village enterprises (TVEs) in rural areas as

government policy aims to diversify rural production and absorb excess rural labour.

Rural industries have been growing rapidly and are expected to continue to do so.

These rural industries are competing with domestic and irrigation demands for limited

supplies of water. They also are much less regulated by the government than are SOEs

and therefore more likely to pollute and less likely to provide water use information.

On average in China only 40% of industrial water is reused in urban industries while in

rural industries the proportion is much lower. In OECD countries about 70 percent of

industrial water is reused (World Bank B 1998).

Other factors that aggravate problem

The water shortage is further aggravated by inappropriate water management methods,

lack of coordination between levels of government and regions and severe water

pollution.

Water Management

• The lack of coordinated management between water using jurisdictions within the

basin cause problems of water shortage and pollution for downstream users. Water

flow coming into Beijing has been reduced by farmers upstream on the Yongding

River in Shanxi and Hebei provinces using increasing amounts of water for irrigation

(Chang 1998). Tianjin’s surface water flows for only a few months in the rainy

season, and then is severely polluted by municipal and industrial waste from Beijing

and other upstream areas.

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• Although there are elaborate water and pollution management systems in place, too

much falls through the cracks due to lack of coordination and cooperation.

“…the Beijing Municipal Water Savings Office does not have formal

relations and engage in significant cooperative efforts with water

management bodies at the National level such as the Ministry of Water

Resources. The continuing lack of coordinated efforts at the municipal

and national level has no doubt held back effective implementation of

water demand management policies in Beijing.”(Tseng 1997, 85)

“each city wants to build a comprehensive system and to act on its own;

they fight for resources and investments, causing very strained relations”

(Wu Liangyong 1988, 66).

“The conflict over water use between industry and agriculture, between

regions and between different sectors in the economy is very prominent”.

(ESCAP 1989, 66)

• Pricing is not being used as a demand management technique. While most residential

water users in Beijing are metered, the meters are not maintained and the water tax is

rarely collected as the cost of water is so low it’s not worthwhile. (Project proposal

1997). In the outer rural areas only a small proportion of residences are metered.

“Cheap water has led to widespread inefficiency in water utilization, encouraged

industries to adopt water-intensive technologies, and generated inadequate funds for

water investment.” (World Bank B 1998, 92)

• In addition to a lack of adequate water pricing strategies, the World Bank lists the

following weakness of the current water management system:

! There is no legal framework for managing water resources along river basin

boundaries.

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! There is no real-time management of water resources in the seven major river

basins.! There is little agency coordination on water projects in the seven major river

basins.

! Provincial water resource planning is designed to maximize provincial

benefits but can result in sub-optimal basin benefits.

! And, water pollution control responsibilities of the river basin commissions

only cover boundary areas (World Bank B 1998).

Impact of shortage

Lack of water is restricting the development of industry and agriculture in the region, and

could be the main constraint on economic development.

• In Shanxi province, China’s coal mining base, water shortages are threatening

industrial growth (World Bank B 1998, Clear Water, Blue Skies, 95).

• Current hydropower installations do not function at capacity due to lack of water

(ESCAP 1977).

• Lack of water was responsible for the loss of more than 650,000 hectares of irrigated

farm land in Hebei in 1996, approximately 15% of total irrigated land in that province

(Almanac of China’s Water Resources 1996).

Short term solutions are being adopted to meet growing demand. Reservoir water

formally earmarked for irrigation is being diverted to Beijing. Ground water is being

“mined” or used at an unsustainable rate, and its level is dropping. The water table has

been dropping, in some areas by as much as one meter per year. Since the 1970s ground

water use has surpassed recharge levels. In the 1950s the water table was 5m below

ground level, it is now 50m below the surface in the most heavily welled areas. The total

area of water subsidence is more than 1000km2 (Pang, 1986). In Tianjin, the water table

has dropped by 60 meters, this groundwater overdraft has caused the threat of seawater

intrusion (ESCAP 1997). By the 1980s thousands of wells along the coast of Northern

China had been abandoned.

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Water transportation has been restricted as water levels in rivers and canals drop. During

the dry season nearly all the middle and lower sections of rivers in the region dry up. The

amount of water going out to sea in North China dropped from 10.48 km3 in the 1970s to

1.46 km3 from 1980 to 1985 (UDNP 1994, Table 2-5). Low water also inhibits the

ability of the river system to flush out sewage and silt.

There are few reports of the impacts on health of the water shortage and pollution. This

is due in part to the health education efforts that have resulted in getting everyone to boil

their water before drinking. There are high fluoride counts in the deep ground water

aquifers in certain areas in Hebei and Shanxi province. As shallow ground water sources

dry up and rural residents resort to deeper supplies, there have been increasing cases of

fluorosis. From 1984 to 1987 in one region of Hebei the number of reported cases

increased by 417,000 (UNDP 1994).

Water Pollution

The Chinese government has defined five categories of freshwater quality standards.

Grades 1, 2, and 3 allow direct human contact and can be used as raw water for potable

water systems. Grade 4 is restricted to industrial use and recreational use other than

swimming. Grade 5 is restricted to irrigation. Below grade 5 is considered a waste sink.

One half of the cross sections used to measure water quality along the Hai river were

found to be below grade 5, none were at grade 1. This high level of pollution is largely

due to the urban areas along the river where large amounts of untreated human and

industrial waste enter the river (World Bank B 1998, 58).

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Figure 3.3. Water Quality in China’s seven main rivers

0% 20% 40% 60% 80% 100%

Daliao

Hai and Luan

Songhua

Huai

Yellow

Pearl

Yangtze

Grade 2 Grade 3 Grade 4 Grade 5 Below 5

Source: Adapted from NEPA, China Environment Yearbook 1996, in World Bank China Library: China 2020 and otherSector Reports

International aspect of the problem

China is the world’s biggest grain producer and consumer. As water shortages decrease

the amount of water available for irrigation grain output will decrease. This situation is

being watched carefully by a number of international observers. “The problem is now so

clearly linked to global security that the U.S. intelligence community has begun to

monitor China’s water situation with the kind of attention it once focused on Soviet

military maneuvers” (Halweil 1998). Despite it’s stated policy of keeping import levels

down, it is believed that China will have to increase the amount of grain they import to

keep up with demand. While with its strong economy China will be able to afford

importing grain, the volume of demand could deplete world grain stores and drive prices

up, therefore creating a life threatening situation for the world’s poorer grain importers

and causing political instability (Brown and Halweil 1998).

24

CHAPTER IV

WATER DEMAND

The basic concepts of demand

In the past, water resource management was a simple matter of projecting current water

use patterns into the future and then meeting that future demand by increasing supply.

However, increasing supply has physical and financial limitations, at some point no more

water can be supplied, or can’t be supplied in a sustainable manner or at a reasonable

price. Because of these limitations, efforts to solve water shortage problems have turned

to reducing the demand for water. Beijing’s water shortage problem “is centuries old,

and has sometimes been solved only through massive public works to increase water

supply. However, reduction of demand now appears to be an unavoidable part of any

solution” (Abramson 1999, 3).

Total water use is water withdrawn from the water source, either surface water or ground

water, it is also called off-steam use. There is also a demand for water that is not

withdrawn from the surface flow. This is for in-stream uses such as hydropower and

navigation, which require a minimum flow. Consumptive use is that part of water

withdrawn and not returned to the immediate water environment for further use. This

usually means water that evaporates, transpires, is incorporated into the product or crops

or is consumed by humans or animals. This definition can also be extended to include

polluted discharge from irrigated fields or industries and water that has percolated to a

very deep water table or that is discharged into salt water. Please see Figure 4.1. for a

schematic of water use in the U.S. It gives the relative size of each sector and its

withdrawal versus consumptive use.

25

Figure 4.1. Water Use in the United States

Source: Henry J., Heinke G. (1989) Environmental Science and Engineering. p. 341

For water use planning it is more important to work with consumptive water use. As

shown below, the relative importance of the water using sectors may differ when the two

water uses are compared.

Table 4.1.Total intake of water versus consumption by sector

Intake Consumption

Total 100% 100%Rural domestic 2% 4%Industrial and misc. 19% 6%Steam and electric utilities 29% 0%Public water 6% 3%Irrigation 44% 50%-65%

Source: Adpated from National Association of Manufacturing and Chamber of Commerce of the UnitedStates, Water in Industry (New York, 1965) In UN 1976 Figure XVI.

26

However, consumptive use data is not always available. For their study of water use in

the Beijing-Tianjin area, Hufschmidt et al (1987) had to use data on total withdrawals as

consumptive water use data was not available.

Components of demand by sector

Domestic

Domestic demand is a combination of residential and municipal demand. Residential

demand is often divided into rural and urban demand. Rural estimates sometimes also

include the water requirements for livestock.

Residential water use in urban areas can be further divided into indoor and outdoor uses,

indoor uses tend to be stable over the year while outdoor uses change with the seasons.

The largest components of indoor uses are toilet flushing (39%) and bathing (30%).

Outdoor water use can range from 0% of total in humid areas to 60% in arid areas (USGS

1996). Consumptive use is usually measured as a percentage of withdrawn water.

In urban areas, per capita domestic water usage is much higher than rural areas and

increases with the size of the area. The main reasons for higher per capita use in larger

areas are:

• an extensive water supply system,

• more non-residential water users (fire fighting, street cleaning, water for

public gardens and parks and for servicing public buildings),

• higher incomes, making urban residents less price sensitive,

• better plumbing facilities,

• increased use of water for the transporting and treating human waste and,

• more water using appliances (Saunders 1969).

Municipal demand includes commercial, institutional, and urban environmental uses.

Commercial and institutional use includes water use for toilet flushing, air-conditioning,

washing floors, fountains, lawn watering, food preparation, and pools. Some of these

27

uses will vary with the season. Commercial water use can be divided into three groups

based on volume of water use.

• Large volume: fish hatcheries and snow making.

• Mixed volume: airports, hotels and resorts, shopping malls, hospitals, amusements

parks, car washes, laundries, office buildings and business parks.

• Small volume: restaurants, banks, stores and shops (USGS 1996).

Environmental uses include watering public green spaces, street cleaning, sewage and

river channel flushing.

Industrial

As development occurs within a country the percentage of total water demand used by

industry also increases. Industrial water demand is usually concentrated among a few

major water users. The following four industrial groups accounted for 84% of total water

used by industry in the US:

primary metals,

chemical and allied products,

paper and allied products and

petroleum and coal products (Jones et al. 1984, 43).

These are national averages. Each region will have its own list of largest water using

groups. And within industrial groups water use will depend on the:

age and condition of plants,

product and processes used,

amount of recycled water used and

quality of the cooling water needed.

Consumptive uses occur as evaporation during cooling and open-air washing or in

product incorporation. For all industries surveyed in a 1978 survey in the US, 62% of

total water intake was for cooling and condensing in steam electric generation, air

conditioning, and other heat diffusion processes (USGS 1996). The amount of

consumptive use of water varies greatly by sector.

28

Table 4.2. Consumptive use of water in Canadian Manufacturing, as a percent of intake

Nonmetallic mineral products 20.0Beverages 19.0Textile products 15.4Plastic products 10.0Rubber products 8.7Refined petroleum & coal prods 6.8Paper and allied products 6.6Foods 4.3Fabricated metal products 4.0Wood 3.6Chemicals &chemical products 3.5Transportation equipment 2.6Primary metals 2.5Primary textiles 2.1Total 5.1

Source: Adapted from Tate D.M. and Scharf D.N. 1992. Tables 3 and 4.

Recycling is an important factor in how industries use water, it reduces withdrawal and

can increase consumptive rates. “During the past two decades, industries have decreased

water withdrawals as they begin to recycle water within their plants to a greater extent

then previously, primarily due to the high cost of waste water treatment required to meet

the provisions of the Clean Water Act. There is an increased consumptive-use rate

associated with recycled water. More recently, industries have decreased water

withdrawals in response to decreasing supply and an emphasis on decreasing use and

production of hazardous-waste materials.” (USGS 1996, 11.F. 1)

Considerable differences are found among industry groups in terms of consumptive

water use and recycling.

29

Table 4.3. Water Recirculation and Consumption by industry in Canada, in Millions of Cubic MetersRecirculation Consumption

Industry group Intake Recirculation Gross Use Discharge Consumption rate (RR) rate (CR)(I) (R) G=I+R (D) C =I-D RR=(R/G)*100 CR=C/I *100

Foods 564 148 712 540 24 20.8 4.3Beverages 63 107 170 51 12 62.9 19.0Rubber products 23 67 90 21 2 74.4 8.7Plastic products 30 66 96 27 3 68.8 10.0Primary textiles 95 30 125 93 2 24.0 2.1Textile products 13 12 25 11 2 48.0 15.4Wood 56 8 64 54 2 12.5 3.6Paper and allied products 3029 2979 6008 2829 200 49.6 6.6Primary metals 1718 1350 3068 1675 43 44.0 2.5Fabricated metal products 25 114 139 24 1 82.0 4.0Transportation equipment 117 237 354 114 3 66.9 2.6Nonmetallic mineral products 90 70 160 72 18 43.8 20.0Refined petroleum & coal prods 487 1068 1555 454 33 68.7 6.8Chemicals &chemical products 1674 1558 3232 1615 59 48.2 3.5Total 7984 7814 15798 7580 404 49.5 5.1Source: Adapted from Tate D.M. and Scharf D.N. 1992. Tables 3 and 4.

Power generation is either looked at as a separate sector or included in the industrial

sector. In a thermoelectric plant most of the water used in the process is used in the

condenser for cooling, it is then discharged as return flow or recycled through cooling

ponds or towers. The volume of water required by thermoelectric power stations and the

rate of consumptive use depends on whether cooling towers or cooling ponds are used or

whether large amounts of fresh water for cooling are pumped in, used and then returned.

In fossil fuel plants water is also used to remove the ash created by combustion.

A hydroelectric dam is typically an in-stream use. The dam and how it is managed can

cause large changes in river flow pattern and have an impact on other water uses such as

recreation, navigation, waste dilution and fishing.

Agriculture

Irrigation is expected to become the key issue of worldwide water resource development

in the future.

• Feeding a growing population with a rising standard of living requires intensive and

expanded agriculture, irrigation is necessary in arid, semi-arid and temperate zones.

• Irrigation is a consumptive use, reducing possibilities for water reuse.

• Large scale irrigation projects and their supply systems can have major impacts on

the local and regional environments (UN 1976).

30

Irrigation water is mostly used for plant growth but it can be also used for frost

protection, chemical application, germination, crop cooling, harvesting and dust

suppression. Water can also be used to maintain or improve the salt balance in the soil.

Much of the water withdrawn for agriculture is stored in multi-use reservoirs. Surface

water delivery systems include natural and constructed channels and pipelines.

While domestic and industrial uses usually return most of the withdrawn water, irrigated

agriculture consumes most of the withdrawn water. Consumption occurs with

evaporation - from reservoirs, conveyance and during application to plants;

evapotranspiration during plant growth; bank storage and return flow to ground water

from leaks or porous soil; and product incorporation. While the measurement of gross

water use is fairly simple, the measurement of consumption and loss is less certain.

Conveyance losses can be a major component of the withdrawals, especially in arid areas

and areas with a low water table. Of the water lost in transit it is difficult to know how

much makes it into ground water. The proportion of withdrawn water actually used by

the crop is very small.

Water intake and uses in an irrigation system in Russia (UN 1976, 105):Used by crops 21%Water losses within delivery system 39%Unused by-pass water 15%Deep percolation from fields 20%Overflow from fields 5%Total intake 100%

LivestockAbout 60% of livestock water is for drinking, the balance covers evaporation from ponds,

cleaning, waste disposal, cooling, processing and water loss.

In stream water users

Along with hydropower plants there are a number of other water uses that require a

minimum of stream flow and for some, quality of water. These include navigation,

recreation (swimming, fishing, boating) habitat maintenance and waste disposal.

31

Forecasting demand

Water management is the balancing act between water supply and demand, both of which

fluctuate over time and space. Water demand forecasting is a water management tool to

explore the water resource impacts of future developments in the national, regional and

local economies (Tate 1977). Long range forecasts of water demand are indispensable to

the management of a municipal water supply. On one extreme they can prevent the over-

commitment of public funds to unnecessary water work projects and on the other extreme

they can prevent future water shortages.

Tate (1977) gives five reasons to forecast water demand:

• to avoid water shortages,

• to ensure sufficient water for the growing energy sector,

• to avoid water user conflicts,

• to support water quality management, and

• to aid international water management.

While all forecasts involve uncertainty, projecting water demand is further complicated

by:

• the possibility of unforeseen changes in the technologies that affect

water-use,

• the difficulty in estimating changes in demographic, economic and

social factors, in terms of natural growth and the impact of

government policy, and

• the difficulty of projecting any changes in the relationship between

these factors and water usage (Saunders 1969).

Planners can use forecasts in a number of ways, ranging from a simple piece of data to a

complete decision-making process. Perhaps the most powerful use of forecasts is

normative forecasting, where projections are used to explore and select goals and

alternatives, to identify appropriate policy rather than work with policies as givens.

32

Forecasters can then work backwards from a desired state, like adequate water supply, to

the policies required to bring it about (Ascher 1978). Tate points out that “the real

benefits of forecasting water demand lie in determining how water demand will vary

under a variety of possible future socio-economic developments, as opposed to

predicting purely quantitative withdrawal or consumptive use at some point in the future

with 100% accuracy” (Tate 1977,8).

While there are many methods to choose from when performing forecasts the most

important criteria for a valid forecast is to include the appropriate assumptions regarding

influential trends. These “core assumptions” are the most important determinants of

forecast accuracy. Core assumptions represent the forecasters’ basic outlook regarding

the context in which the forecasted trends exist. Establishing core assumptions and

testing their validity is of greater importance than developing sophisticated techniques.

“Forecasting methodology is as much concerned with finding the appropriate

assumptions as with calculating expected water use given the assumption.” (Jones et al

1984, 62). Forecast accuracy is based on the selection of proper assumptions and the best

current data that reflects important trends. The “forecasts that do appear to be much less

accurate than others often turn out to rest on antiquated information, or to have been

influenced by major events in the course of the trend in a way not at all anticipated by the

forecaster.” (Ascher 1978,199). It is therefore important to incorporate into the forecast

the most recent data and assumptions regarding trends. If accurate data is not available to

determine trends “multiple-expert-opinion forecasts, which require very little time or

money, do very well in terms of accuracy because they reflect the most up-to-date

consensus on core assumptions” (Ascher 1978, 201).

It is important to gauge the importance of each background forecast to the final, or

aggregate, forecast and allocate effort accordingly, those forecasts with the greatest

impact on the final forecast get the most attention. Those background forecasts with the

greatest inaccuracy also demand extra attention.

The following are further important considerations when developing a forecasting

method:

33

• forecast objectives,

• data availability,

• geography of the area,

• core assumptions,

• water pricing,

• level of disaggregation,

• taking the unknown into account, and

• a basic framework.

Objectives

From the outset the forecaster must be clear on the objectives of the forecasting exercise.

This includes what is to be forecast and how the resulting forecast will be used and by

whom. This will help determine the approach, including the level of detail and analysis

that is required.

Data availability

Many models depend on years of historical data to forecast future trends. The choice of

the best water demand forecasting method is dependent on the amount of data that can be

collected, its relevancy and reliability. “Highly sophisticated models may thus be of little

value if their data or validation requirements are too severe. It may be that initial

methodologies should be quite simple, with increasing sophistication, aimed at greater

accuracy and confidence, being incorporated as more data become available and as

experience is gained”. (Tate 1977, 11)

The geography of the area

The forecast area must be defined before data collection or a choice of methodologies can

be made. It is important to match the area of demand with the area of supply. In Canada

some water demand forecasts have been based on the river basin as the principal spatial

unit. The service area of one or more water utilities can also be chosen. However,

collecting socio-economic data for these areas will be a challenge as they are not usually

the spatial unit for data collection or provision. If the area includes coastal regions

34

projections of withdrawal must be adjusted if salt water is used for industrial and power

production cooling. As well, water users on the coast who get their water from fresh

sources should be segregated as all of their withdrawal will be lost as discharge into

tidewater. Ground water basins do not usually match river basins. The region should

also be divided in to ground water basins and the demand estimated for each one.

Primary determinants/core assumptions

Identifying the primary determinants of current and future water usage is a necessary

prerequisite in the creation of a forecasting method. Where the trends of certain variables

are obviously going to have an impact on future water use they must be explicitly

included in the model. Water conservation methods must be considered if recently

installed or considered. Technological change has a large potential impact on water

demand but is very difficult to forecast.

Water pricing

Traditionally in the USA and Canada water has been perceived as a free commodity, and

pricing has not been used as a tool to reduce demand. However, above the minimum

basic need for water for drinking and sanitation, water demand behaves like the demand

for most other goods and services. Residential water uses are responsive to price,

especially outdoor uses, and can be reduced by metering and pricing schedules.

Industrial users will also reduce withdrawals in response to price increases. In terms of

cost, water is not a major input factor for industrial development. Compared to the

domestic and agricultural sectors the industrial sector has a much greater opportunity for

improving water use efficiencies and pollution control through pricing and other

economic incentives (UN 1976). Effluent discharge fees can be used to reduce industrial

water use (Tate 1977). The use of econometric models allows for the impact of price

changes to be incorporated into the forecast method.

Disaggregation

Disaggregation allows for greater forecast accuracy as each sector can be forecast

separately based on the trends that affect it specifically. The most common way to

35

disaggregate water use forecasts is by sector, time of year and geographic area. When the

data is available, disaggragated models produce much more useful, accurate and flexible

models than do simpler, aggregated models.

Taking the unknown into account

With basic forecasts the unknowns of the future can be taken into account by making

projections of the population and economic activity for at least three intervals, low,

medium and high (UN 1976). With a more complex forecast, assumptions about the

future are made explicit in the model and various combinations of influential factors are

examined. This “alternative futures framework” might include the following:

• assumptions about future population trends,

• economic growth assumptions,

• assumptions regarding technological developments related to water use,

• effects of alternative macro-economic policy alternatives,

• effects of pricing policy of water and other elements of water management,

• effects of policy to promote environmental quality (Tate 1977).

“The preparation of alternative futures is most useful where significant uncertainty exists

concerning key assumptions or projections of explanatory variables, where the reliability

of future water supply is an important concern, or where a range of policy options is to be

investigated” (Jones et al 1984, 69).

Another way to incorporate uncertainty in a forecast is to use the contingency tree

method. Once a base forecast has been prepared possible sources of uncertainty with

regards to future water use are identified. Probabilities are then estimated for each

possible outcome and the forecast is adjusted to reflect the effects of all the possible

combinations of the uncertain factors and joint probabilities are attached to each possible

outcome.

For their forecasting exercise, Hufschmidt et al (1987) divided the various elements that

affect future water use into internal and external factors. Internal factors include prices,

regulations and other policies while external factors include sectoral growth rates,

36

technological change, prices of inputs and other macro variables. As a base for

forecasting, current internal factors must be described and assumptions about external

factors stated. While the authors realize that the distinction between internal and external

factors are somewhat artificial, they believe it is important as a first step to understand

current water use and its growth based only on external factors and in the absence of any

changes to water pricing and management policies. Various policy options (internal

factors) can then be analyzed for their impact on water use.

The basic framework for water use and demand forecasting

Tate (1977) recommends that demand forecasting proceed from the national to the local

level, this allows for the basic data that is most likely available at the national or

provincial level to be used as a framework for the exercise. The forecasts for all the local

areas must add up to the national or regional forecasts. While the national level data

gives the framework, it is at the river basin or local level, where supply and demand can

be compared that most of the analysis and projections will be carried out.

Models

Modeling is “the mathematical expression of the structural relationship between the

forecasted trend and other factors”(Ascher 1978, 210). Models serve as accounting

devices that follow the implications of growth assumptions, reducing the possibilities of

inconsistencies and allowing for the incorporation of more detailed data and assumptions

“mathematical modeling stands as the ‘great hope’ for forecasting in almost every area.”

(Asher 1978, 210) However, the relationships that are used in models are based on

current and historic conditions. These must continue into the future for the model to be

reliable. In a time of rapid structural change forecast methods that rely on fixed

structures are more appropriate for short term forecasts.

Simple Coefficient methods

Currently, most models used to analyze water demand use the coefficient approach.

“Applied water use and demand studies in Canada have been, for the most part, quite

elementary in nature, and have relied almost exclusively on a coefficient approach” (Tate

37

1977, 26). The coefficient method is frequently used in the USA as well and produces

good forecasts where customers are homogenous. It is typically used in communities that

cannot develop water-use data and sector composition data at a reasonable cost.

The most basic coefficient approach is to determine a single per capita water use

coefficient based on total water use in the study area, it is then applied to population

projections. Forecast accuracy improves when coefficients are determined for the main

water using sectors (domestic, industry, agriculture). But since there can be wide

differences in water use within these sectors it is most preferable to further divide sectors

into their component parts and apply component-specific coefficients. For the domestic

sector that would include coefficients for households, commercial and institutional water

use. This way trends that affect water demand, like modernization of households, can be

isolated.

It is preferable to use coefficients that were calculated in the region being modeled, or at

least a similar region. In Canada, coefficients from the U.S. are often used. Water use

coefficients are not regularly calculated by any water agency in Canada or the US. They

generally come from four sources:

1. case studies of single water users or small groups of users,

2. surveys of users where the total amount used and the percentage used

for each end use is reported,

3. measurements of the efficiency of a specific water-using practice or

technology,

4. calculations from aggregate water use and statistical or demographic

measures (Brooks and Peters 1988, 73).

The coefficient method is appropriate when data is limited and extreme accuracy and

detail are not required. It is based on the assumption that current water use can be

determined by past trends and that the relationship among the variables that affect the

level of water use, like price, income, weather, irrigated land, commercial space are

expected to remain the same.

38

Multivariate methods

As more data becomes available, regression models can be substituted for coefficients.

The basic method of water demand analysis is curve fitting, which is used to determine

the relationship between water demand and the factors that influence demand.

Multivariate models include a number of variables (population, households, income, lot

size, land-use densities, seasonal patterns, employment, weather variables). Dummy

variables are often included to measure the effect of dichotomous, or on/off conditions,

like water use restrictions.

These models can also be referred to as econometric models when they use mostly

economic variables such as household income, marginal and average water prices and

employment. Econometric models are especially appropriate for estimating total public

water supply, water withdrawals and deliveries. The Corp of Engineer’s Institute for

Water Resources-Municipal and Industrial Needs Model (IWR-MAIN) is one of the most

frequently used models in the U.S. Econometric models are also used to determine

economic impact (Leontief input-output) and economic cycles and interactions among

variables such as income, employment, and interest rates. These more complex models

are rarely undertaken as there is usually not enough historic data for them. Non-

econometric models, or requirement models, do not include price or economic factors, in

these models water use is considered a necessary requirement unaffected by price.

Time series, cross sectional models

These models also use regression analysis. Time series models look at water

consumption over time, either months or years. Trends in water use can be identified and

hypothesis about future use developed and tested. However the main explanatory

variables that influence water use in the past may not have the same influence on future

use. Cross sectional models look at the effects on consumption by the explanatory

variables within different geographic areas at one time period. It is then assumed that the

relationship between these variables will remain the same in the future. “It is desirable to

specify a model that will adequately allow for the differences in behavior stemming from

39

the cross-sectional attributes as well as any differences in behavior over time for a given

cross-sectional attribute”(Weber 1993, 64) Time series and cross sectional data can be

used in a single regression analysis, but more often they are treated as alternatives.

Two comprehensive forecasting models

In the 1960s, Howe and Linaweaver developed a residential water demand model using

three dependent variables; average daily domestic demand for water (indoors), average

daily sprinkling demand (outdoor) and maximum day sprinkling demand. The

independent variables used were: property value, evapotranspiration, and the marginal

price of water. This study led to the Hittman Associates Municipal and Industrial II

Model (MAIN II). The model is now computer based to simplify data storage and

manipulation and allow for more detailed disaggregate forecasts. Urban water customers

are grouped into four sectors: residential, commercial/institutional, industrial and public

and unaccounted uses. Each sector is further dissagregated as needed for forecasting; for

residential users this could mean those who are metered and those who are not.

Residential water use is based on the econometric model of Howe and Linaweaver.

Industrial water and commercial/institutional demand is determined using water use

coefficients. Some public demands are based on a per capita employment.

A complete set of base year data and some historical data are required as input. Four

types of forecasting methods can be used depending on the availability of data:

Projection by internal growth models;

Projection by extrapolation of local historical data;

Use of projections made external to the model and provided as input by the user;

And any combination of the above.

Jones et al. (1984) list the following as cautionary notes to users the model:

• While the quality of the all forecasts depends on the quality of data used, inaccuracies

in base year data with a complex model like MAIN II can adversely affect the

forecasts in ways that are not obvious.

40

• Application of the model is limited, the internal growth models assume a large

metropolitan area that has experienced and will continue to experience positive

growth.

• Users of the model must make sure that the most recent trends and patterns are

incorporated, either in the internal growth models or by inputting them themselves

Water Use Analysis Model

This Canadian model, developed by Environment Canada, has seen only limited

application to date. It is much more comprehensive than MAIN II, it’s a water

management model for a large region rather than a urban water demand model. While

water use projection is the primary focus of this model its other components include

water supply and water balance. The focus of the following description is on the water

use component.

Withdrawal water uses are grouped into six categories

Urban-municipal

Industrial

Irrigation

Livestock

Power generation

Special development

Non-withdrawal uses include recreation and waste dilution

Figure 4.2. shows the calculations in the model that are determined at subbasin level at

monthly intervals.

41

Figure 4.2. Calculations at each node

Source: Kassem et al. 1994, Figure A-4

The most interesting part of this model is that water supply and demand are balanced at

subbasins within the river basin. The network includes nodes (subbasins), links (flow

path between nodes) and irrigation areas. The user determines the relationship of the

subbasins and the irrigation areas within them. The network must be dendritic and

converging downstream. Water use projections are made for each node based on

assumptions about the future. The model then performs the water balance calculations,

starting with the upstream nodes and moving downstream. The entire network is dealt

with for a given time period before moving on to the next. Two main water use

parameters are calculated, water intake (withdrawal) and water consumption, the

remainder is water return.

For in-stream water use minimum monthly required flows are specified. The model

calculates net outflow from a subbasin as the difference between available supply and

total consumption. This outflow is then compared to in-stream water requirements.

42

For domestic and industrial use water demand is determined using the basic coefficient

approach. Forecasts depend on estimates of growth. Growth factors are modified to

allow for differences among subbasins and changes in water use practices like increasing

recycling. WUAM also uses national and provincial input-output matrices to establish

inter-industry growth impacts. Consumption is expressed as a percentage of intake.

The irrigation submodel is more complex. Estimates are made of monthly water

requirements for crops, irrigation diversions and return flows, that take into account crop

type and mix, precipitation, crop evapotranspiration, soil type and moisture levels, as well

as type of irrigation system and management practices. Historical precipitation and

evapotranspiration data are used with water supply data to calculate irrigation

requirements. The basic calculations are made for the growing season and for an historic

period of years (Kassem et al. 1994).

The impacts of water price changes are measured in the urban-municipal and industrial

sectors. Water demand curves are defined representing the relationship between quantity

used and price. Two additional pricing algorithms, based on regression analysis of

industrial water use are available, the price coefficient method and the price elasticity

method.

Previous studies of the water shortage in Northern China

The water demand and supply equation of Northern China has been studied quite

extensively. Currently the U.S. department of Agriculture is estimating water demand in

the area. Their interest lies primarily in estimating the demand for water for irrigation

purposes. The following is a brief description of three studies that were available in

English.

43

Water Management Policy Options for the Beijing-Tianjin Region of China - 1987

This report was written by the Environment and Policy Institute, North China Water

Policy Team, East-West Center in 1987. It is a draft version that’s not to be cited without

permission.

The work was done by the East West Center with the National Research Center for

Science and Technology for Development of China, part of the State Science and

Technology Commission, in consultation with various American, international and

Chinese experts.

The goal of the work was to:

• examine the present and future water situation in the Beijing-Tianjin region,

• identify management and policy options that will balance water supply and demand

over the next 15 years and,

• present a policy analysis of water resources management for Beijing and Tianjin.

This report is a draft of the EWC’s part of phase one. The Chinese team of researchers

wrote up their own report. A second phase, to be organised by the Chinese team, would

be a set of studies to develop feasibility reports for individual demand and supply

management projects.

This is a very useful report for a number of reasons, it takes a very simple yet

comprehensive approach to water management in the area, it provides Chinese water use

coefficients for a number of sectors and it lays out the technical options that could save

water. It also shows what policy options are required to achieve the water savings, the

quantity and quality of the water saved, the costs of the technical options, their

implementation difficulty and who would pay for them.

For our purposes the study is limited by looking at only a relatively small part of the river

basin.

44

North China Water Management Study - 1994

This study was funded jointly by the Untied Nations Development Program and the

Government of China. It was managed by three different agencies, the UN Department

of Development Support and Management Services, the State Science and Technology

Commission and the Ministry of Water Resources. The work was carried out by the

Research Center of North China Water Resources, part of the China Institute of Water

Resources & Hydropower Research, in consultation with international and domestic

experts from various agencies.

“the main output of the Project is a macro-economic water planning model which will

take into consideration the benefits of conflicting demands on limited water resources,

balancing the economic, environmental and social considerations”(UNDP 1994, S-2)

The objective of the project was to improve the economic value and efficiency of water

use in North China so as to support the targets set by the Government’s Seventh Five

Year Plan for Economic and Social Development (1986-1990).

There were four parts to meeting this overall objective.

• Macroeconomic based water resources planning and management models for North

China.

• Hydrologic models to support future water management models for smaller areas in

Northern China and water balance models for Beijing, Tianjin and Ningbo.

• Studies of specific local water problems in various regions to be integrated into

planning models:

agricultural water saving and wastewater treatment,

groundwater pollution and water management,

waste water treatment and water management, and

macroeconomic water planning model.

45

• National and provincial data systems to support hydrologic, management and

planning models.

The project looked at all of Northern China as well as specific problems faced in eight

subcentres; Beijing, Tinajin, Shanxi, Shandong, Qingdao, Weifang and Ninbo. The main

focus was on the five cities of Beijing, Tianjin, and three cities in Hebei province;

Tangshan, Qinhuangdao and Langfang.

This was a massive study, reported in three volumes, heavily reliant on advanced

mathematical and econometric models. The basin itself is not studied as a unit. The work

that was done in the subcenters provides useful coefficient information.

Study on Assessment of water resources of member counties and demand by user sectors.

China: Water Resources and their use - 1997

This study was organized by The Economic and Social Commission for Asia and the

Pacific of the United Nations, financed partially from the Government of China. It was

drafted by the Nanjing Institute of Hydrology and Water Resources of the Ministry of

Water Resources of China.

This report provides current and historic water supply and water use data for the nine

hydrological regions of China, including the Hai basin. It also forecasts water use by

sector and region until 2010. These forecasts will be useful for comparison purposes.

Unfortunately there is no water use coefficient data provided or detailed water use data

within the major sectors. The report also includes a discussion of water resource and

management issues within China.

46

CHAPTER V

SUGGESTED APPROACH

Overview

As we learned in Chapter IV, creating a water demand estimation model is complex.

There are a wide variety of interrelated factors that have to be taken into account to

determine current and then estimate future water demand. Creating a model for this

region of China is even more challenging. Data is limited, the scope is massive and the

future does not necessarily project based on past trends. Because of this the objective of

the model cannot be accuracy but rather a way to explore possible demand management

options. Therefore a base line equation should be laid out first that projects current

water use trends. Then the impact of various options can be compared to this base.

At this point available data on the water using sectors in the region is very basic.

“It should be pointed out that in China the water-use reporting system has not been well

established….There are no legal provisions or regulations for performing the systematic

collection of water-use data or reporting on the water use” (ESCAP 1997,56).

Therefore a simple water demand estimation model will be set-up that will, as more

refined data becomes available, increase in precision over time. A unit-use coefficient

approach will be used to estimate water use by sector.

The supply and demand equation is most easily balanced at the river basin level.

However supply and demand varies from one area to another within the basin. Surface

water, ground water, rainfall and water users are not evenly distributed throughout the

basin. Further, upstream users have an impact on the quantity and quality of water

available to downstream users. Therefore to ensure a sufficient quality and quantity of

water for all users the model should include a spatial component that in effect tracks the

flow of water from upstream to downstream users. This component also allows planners

to make locational decisions for current and future water users. The spatial component

also allows for a realistic sharing of the resource. Water savings by one sector are only

47

useful if the saved water can be used by another sector. For example, water saved in the

city by increased industrial recycling can be used for domestic uses, but water saved by

more efficient irrigation methods in Shanxi province may not necessarily translate into

more water available for domestic use in Beijing. The key elements to tracking the flow

of water are measuring consumed water rather than total withdrawals, and estimating

how pollution decreases the amount of water available for reuse.

Since both the demand and supply of water varies throughout the year and from year to

year the model should take these variations into account to ensure that water users have

access to the water they need throughout the year and in dry years.

Process

! Determine the flow of water through the basin and divide the basin into regions,

probably by sub-basins, where supply and demand can be balanced.

! For the entire Hai river basin and by each of the regions, collect the most recent and

historic data on the main water using sectors.

! Collect the most appropriate coefficients by sector, adjust where necessary to reflect

water consumed as opposed to total withdrawals.

! Using basic sampling techniques, conduct surveys to refine the demand equations

within the major water using sectors and regions. Surveys should also provide

information on water use throughout the year, in dry versus wet years and estimates

on consumed water, including polluted water.

! Based on historic data and documented trends, establish growth scenarios for sectors

by region.

48

! Create a range of coefficients that reflect how water use may change by sector and

region based on various water management options.

! Create separate models for each region. Please see the Table 5.2. for an example of a

water demand model for Tianjin.

! Link the regions together based on the water flow through the basin. Run the model

with the baseline coefficients and growth trends for all sectors and regions.

! Establish water use priorities (most probably based on the economic value of water)

and re-run the model with various water demand management options chosen to meet

those priorities.

! Determine those combinations most likely to match priorities and balance supply and

demand now and over the next 20 years.

Data collected

The objective of the second step in the process was to collect current and historic data on

the major water using sectors for the Hai River Basin and by region. Sectors include

agricultural, industrial and municipal water use.

The basin was defined by digitizing a basin map supplied by the Hai River Basin

Commission in Tianjin onto the GIS map of China provided by the China in Time and

Space (CITAS) web site. It was determined that the basin includes all of Beijing, Tianjin

and Hebei province as well as parts of Shandong, Shanxi and Henan provinces, for a total

population of 143 million in 285 cities, districts, counties, autonomous regions and

prefectures (this includes all metropolitan areas that were at least partly within the basin).

49

Sources for the data were primarily the yearbooks of each province. Water supply data

came from the Urban Construction Statistics Annual Report, Department of Planning and

Finance, Ministry of Construction.

Data was collected for the following variables for 1980, 1990, 1995 and 1997.

There are many gaps in the data. This is partly because the data recorded by the

yearbooks is not always consistent between years or between provinces, partly because

the data collection method was not flawless and partly due to the difficulty of getting

access to available data within the time frame allocated for the research trip.

DomesticPopulation

Non-agriculturalAgricultural

HouseholdsNon-agriculturalAgricultural

Urban and rural population figures was not collected per se, but can be determined by

summing the population figures of urban and rural districts. Although critical to

determining future residential water use, no data was found on household or housing

type.

Agriculture

Irrigated landCrop landCrops: Total grain

RiceWheatCorn

Vegetables

Livestock:LargePigsSheep/GoatsPoultry

Fresh water fish

50

Industrial output

Food and beveragePaper and paper productsChemicalCrude oilCoalMachineryFerrous metalTextilesBuilding materialSalt

Thermal electricity

Based on fresh water consumption, these are the top water using industries in China

(Tang 1993). Thermal electricity is also included because, while it consumes very little

water, it requires a great deal for cooling. Industrial output by ton was collected for each

industry (kwh for electricity). There are many gaps in the data, the industrial listings in

the yearbooks were not consistent from year to year. Also, only in the Hebei yearbook

was industrial output provided by metropolitan area, all other yearbooks provided

provincial totals only. For Tianjin and Beijing, industrial output data was not available

by district or county, only for the entire metropolitan area.

Commercial/Public

HotelsSchoolsHospitals

Although they are important components of commercial and public water use no data was

found for office or retail space. Some yearbooks did record data on employees in retail,

which could be used instead, but that data has not been incorporated into the database.

Water supply

Production capacityGround water

Total supplyIndustrial usage

51

Municipal usageResidential

Population servedNon agricultural

Supply data for municipal areas was provided by source of supply. For 1990 and 1997

data is available for water supplied by the Urban Public Utility Authority. For 1997 it is

also available by “out of jurisdiction of urban public authority” and “self-managed water

resource”.

Please see Appendix A for a complete listing of the data included in the database, and

Appendix B for notes on the data collected.

Options to reduce water demand

“To solve the water shortage problems of these areas, the productive structure of

agriculture and the distribution of industry must be reasonably regulated. The choice of

agricultural and industrial development as well as urban and rural construction in the

north should be suited to the actual condition of water scarcity and the difficult question

of water supply in the area” (ESCAP 1989, 77).

Many of the options presented here to reduce water use would require reversals of current

trends.

Irrigation

Within the Hai basin, irrigation is expected to account for 62% of total water demand in

2000 (ESCAP 1997).

As irrigation is by far the greatest user and consumer of water, even small savings per

hectare will have a large overall impact on water available for other uses. The options to

explore include reducing the irrigated area, changing the crop mix, decreasing loss of

water in conveyance, improving irrigation efficiency, and using saline water to irrigate.

52

Reduce irrigated land

Loss of farm land to development is already occurring at a rapid rate around major cities.

From 1990 to 1997 in Beijing and Tianjin the amount of total irrigated land decreased

from 681 to 561 thousand hectares. The majority of this loss was due to development.

However, looking at the basin as a whole, these losses to irrigated land are far

outweighed by the gains reported in Hebei province, where irrigated land increased from

3.76 million hectares in 1990 to 4.32 million in 1997 (Project database 97).

Change crop mix

Water application rates for selected crops in Beijing and TianjinCubic meter per hectare per year

Low HighWet rice 7,500 13,650Vegetables 11,250 15,000Wheat 4,000 4,230Orchards 2,625 3,930Melons 1,500Edible Oils 1,200 1,725Corn 600 1,500

Source: Adapted from Hufschmidt et al 1987 Table VII-1

Large water savings are possible by changing cropping patterns. Rice and vegetables use

the most water per hectare. Recently, within both Beijing and Tianjin, the area planted

with these crops has been increasing. In Beijing, from 1990 to 1997 the number of

hectares planted with rice decreased from 34,000 to 23,000 yet hectares of vegetables

increased from 70,000 to 89,000. In Tianjin, the number of hectares of rice increased

from 45,000 in 1990, to 65,000 in 1997. Hectares of vegetables increased from 55,000 to

96,000 (Project database 1999).

In their study of Beijing and Tianjin, Hufshmidt et al (1987) point out that due to

inadequate transportation and storage facilities this area has a heavy reliance on the local

supply of food, especially fish and vegetables, both major water users. Importing these

products from water rich areas should also be explored.

53

Improve efficiencyThe current irrigation and drainage systems are in poor repair. There were hastily

designed and constructed in the 1950s and 1960s, not well built, and often left unfinished.

Today these systems are poorly run and maintained. Relining canals and using low-

pressure pipelines on existing systems would save large amounts of water (World Bank A

1998).

A large proportion of water is lost in transportation, first from reservoir to field, then

from irrigation channel to crop. There are two main ways to improve irrigation

efficiency. The existing flood type irrigation systems can be improved by leveling and

contouring the fields to allow for more even distribution of water, and/or by improving

the match between the plant’s need for water and its application. The irrigation system

can be upgraded to a more efficient one, either sprinkler or drip.

Tianxin and Kang (1997) estimate that the flooding method consumes more than 1000 m3

of water per mu (there are 15 mu per hectare), while the spray method consumes 500 m3

and the drip method 300 m3. When the 350,000 mu of grain fields in Beijing’s Shunyi

County switched from flooding to spray technology productivity increased by 20 percent

and water savings increased by 55 percent.

Use saline water for irrigation

It might be possible to use salt water to irrigate certain crops along the coast. “Study

after study shows that desalination is the major long-term answer to the problems in most

water-starved areas” (Paul Simon The Montreal Gazette 13 April 1999). Crops such as

barley, cotton, sorghum, soybeans, sugar beets and wheat are moderately tolerant of salt

water. Some field and tree crops in Saudi Arabia are irrigated with water with a low

concentration of salt (Hufschmidt et al 1987).

Industrial water use

54

Within the Hai basin, industrial water use is expected to account for 20% of total demand

in 2000 (ESCAP 1997).

Change the industrial mix

As with crops, different industries require different amounts of water. As a hold over

from the communist era the current mix is weighted towards heavy industry, major water

users and polluters. Two thirds of Beijing’s and one half of Tianjin’s industrial output

value comes from heavy industry (1998 Yearbooks). The following table lists the range

of water use by selected industries.

Industrial Water Demand 1990(m3/1,000 yuan output)

Beijing TianjinConstruction 2.0 2.0Service 4.0 4.0Light manufacturing 6.0 8.1Heavy manufacturing 11.8 7.4Mining 6.8 45.6

Source: Adapted from Table 8-3 UNDP 1994

The following industries are the main water using industries within Beijing and Tianjin:

Water Use% of total Use rate

Industrial water usem3/10,000 yuan*BeijingChemical 30.6 355Machinery 16.6 126Metallurgy 15.8 357Textiles 8.6 196Construction materials 7.0 481Food 7.0 223Total 85.6

TianjinChemical 28.3 314Machinery 15.1 86Petrochemical 14.1 568Textiles 11.7 104Pulp and Paper 8.4 994Food 7.6 175

55

Total 85.2* based on gross value, these figures do not net-out costs of other inputs for eachindustry.Adapted from Table VII-4 Hufschmidt et al. 1987

If we look at the three industries with the highest water use per yuan output, we see the

following change in ton output from 1990 to 1997:

Beijing: Construction materials + 337%Metallurgy* + 87%Chemical - 24%

Tianjin: Pulp and paper + 52%Petrochemical** + 38%Chemical + 33%

Source: Project database 1999* for Metallurgy using Ferrous metals** for Petrochemical using crude oil

Change the location of industries

The spatial distribution of industries is changing. Industrial growth until the reforms of

1978 was concentrated in the cities. In the past 20 years there has been a growth of town

and village enterprises in the rural areas. In Beijing industries are being slowly moved

out to suburban and satellite locations. A proposal was made in the late 1980s by the

Institute of Geography, Chinese Academy of Sciences, to form an economic region of

Beijing, Tinajin and Hebei. Within this region industries could be relocated to take

advantage of the best supply of inputs and transportation connections. As Beijing is short

of water, short of energy and is an inland city, heavy industry would be much more

efficiently relocated on the coastal area of Bohai bay. Cooling water for these industries

could be supplied by sea water (Cheng 1998).

The biggest drawback to regional economic planning is the current emphasis on localism.

Since the reforms the central government has pulled back from regional planning and

each area has focused on increasing its own economic well being. “China is not short of

good plans, proposals, or resolutions, but there is a serious lack of coordination and

determination to implement them” (Cheng 1998, 19).

56

The main transportation link between Beijing and Tianjin, the Jing-Jin-Tang expressway,

is the site of major industrial development. The city of Langfang, located within the

Beijing-Tianjin corridor 60km from both cities, is a popular area for high tech industrial

location, however, its growth is limited by water shortages. The Shunyi airport new

town, north east of central Beijing, is also anticipated as an important area of future

growth.Figure 5.1 Jing-Jin-Tang Development Corridor and Sunyi Airport Zone

1. Beijing Economic & Technical Development Zone A. Capital International Airport2. Yongle Economic Development Zone B. Shunyi Development Zone3. Langfang Economic & Technical Development Zone4. Langfang High Tech Development Zone5. Yat-sen International Scientific Park6. Wuqi County Development Zone

57

7. Tianjin High tech Industrial Park8. Beichen Development Zone9. Tianjin Economic and Technical Development Zone

Source: Adapted from Map 3. Liangyong and Qizhi. 1995. The Integrated Development of theBeijing Metropolitan AreaImprove efficiencyIn China more water is used per value of production than in industrialized countries.

In 1989, for every 10,000 yuan of industrial output China used 270-500m3 water while

industrialized countries used 20-30 m3 (Tianxin and Kang 1997). Outdated production

technologies and low recycling contribute to this excessive water consumption. In North

China for every ton of steel output 25-56 m3 of water is needed. In the USA, Japan,

England and Germany only 5.5m3 is needed (Tianxin and Kang 1997). The Chinese

paper industries consume 400–500 tons of water to produce one ton of paper product,

OECD countries consume 5–200 tons (World Bank 1998 Clear Water, Blue Skies).

However there have been improvements, especially in northern China. In Beijing and

Tianjin between 1978 and 1984, industrial output increased by 180 percent and 160 per

cent respectively, while freshwater intake in the industrial sectors fell. This was due

mostly to increased recycling, from 46 per cent to 72 percent for Beijing and from 50

percent to 73 percent for Tianjin (ESCAP 1997).

Rural industries have been growing rapidly and are expected to continue to do so as

government policy aims to diversify rural production and absorb excess rural labour.

Unlike state owned industries, TVEs are unregulated and little information is available

about their water use. On average only 40 percent of industrial water is reused in urban

industries while in rural industries the proportion is much lower. In OECD countries

about 70 percent of industrial water is reused (World Bank B 1998).

Use sea water

Not all industrial water needs have to be met with fresh water. In 1975, along the coastal

regions of the USA, 50% of the cooling water used by thermal power plants was supplied

by sea water. In 1989 21% of water used by Japan’s manufacturing sector came from the

sea (Cheng 1998). In Tianjin the electric power industry already uses little freshwater as

many facilities use seawater for cooling.

58

DomesticIt is estimated that 10% of total water use in the Hai basin will be for domestic demand in

2000 (ESCAP 1997).

The options explored by Hufscmidt et al. (1987) for Beijing and Tianjin include water

saving devices in homes, offices and commercial buildings; reducing loss due to leakage

and changing the vegetation cover.

While the quantity of domestic water is relatively small it has to be of the highest quality

and be reliably supplied. Because of its value, domestic water uses and losses have to be

kept to a minimum. However, both rural and urban per capita water use is expected to

increase as living conditions improve. For example, per capita water use projections for

Tianjin are as follows:

Table 5.1Population and Water use estimates for Tianjin

Urban areas Rural areasResidential Municipal Town Village

pop water use pop water use pop water use104 l/c/d l/c/d 104 l/c/d 104 l/c/d

1990 522.6 96 101 31.7 110 373.3 602000 565.8 128 142 39.0 140 417.3 1002010 703.3 140 164 48.4 160 405.0 120

Source: UNDP (1994) Appendix G

Typically, residential water use levels are highly correlated to the water supply and water

using facilities within the home. For example in Tianjin in the 1980s, people living in

courtyard homes with no plumbing and supplied by a stand pipe used 50 liters of water

per day. Those living in low rise apartments with plumbing used 69 liters and those in

high rises, 107 liters per day (Hufschmidt et al. 1987). Unfortunately data on water

supply and housing type is difficult to attain.

59

The current urban policy is to control the future growth of large cities, develop medium

sized cities and expand small cities. Construction in new developments could be fitted

with water saving devices that could go far in reducing the projected water use per capita

for both residential and municipal uses. Depending on the model, new style toilets can

use from 30 percent to 90 percent less water than conventional toilets, showerheads from

40 to 90 percent less and faucets up to 50 per cent less than traditional models.

Even within the older areas major water savings are possible. In Boston water demand

decreased by 24% by repairing leaky pipes, installing water saving devices and educating

the public about water saving measures (O’Meara 1998). Other water saving options can

include reusing partially treated wastewater for toilet flushing and lawn watering.

City beautification policies have increased the demand for municipal water for plant and

lawn watering. Over the past four years in Beijing an average of over three million trees

have been planted each year (Beijing 1995 and 1997 Yearbooks). The tree planting level

in Tianjin is much more modest, with an average of 800,000 planted each year over the

past two years (Tianjin 1997 Yearbook). While urban trees provide many benefits, they

require large amounts of water. Similarly, in rural areas of the Hai basin tree planting

programs to prevent flooding and soil erosion probably result in an increased demand for

water. Preferable soil protection methods include terracing sloped surfaces and planting

with grasses and other less water demanding plants (Hufschmidt et al. 1987).

Sample water demand estimation model

An example of a water demand estimation model was developed for Tianjin. Tianjin was

chosen because the data available for this area was most complete. This is not a

forecasting model, it is a preliminary exercise to layout all the key elements in water

demand and see how well we can balance this demand estimation with supply of water

and other demand estimates.

60

Figure 5.2 Tianjin – Administrative Boundaries

Source: Website: sedac.ciesin.org/china

61

The data for each sector comes from the Tianjin 1998 Yearbook, for the year 1997. The

water use coefficients come from a variety of sources:

Domestic

Urban, rural and environment water use coefficients are from the UNDP study, the

Tianjin section. This study provides 1990 actual figures and estimates for 2000. For the

model, figures for 1997 were calculated at 78% of the difference between these two

figures. Infrastructure water use includes green space maintenance while environmental

water use is for maintaining river water quality and quantity.

The proportion of loss is from the EWC study. While the Chinese team on the EWC

project determined water loss figures for the three sectors they are not included in the

EWC report. The American team wanted to compare Tianjin’s figures with those of

Beijing figures, which were net rather than gross, they were also unsure of how the loss

figures were derived and they believed that most of this lost water would be returned to

the water system for reuse. The loss proportions are included here for three reasons; we

don’t have to worry about comparing with Beijing figures in this exercise; compared to

the loss proportions reported elsewhere these proportions seem quite low and reasonable

for net loss to the water system and, due to high levels of water pollution from all three

sectors there is a loss to the system even when water is returned to it.

Agriculture

Irrigation coefficients are from the EWC study, which provided both a high (75%

reliability) and a low (50% reliability) figure. Data was not collected for orchard

irrigation, therefore orchard water use was calculated as a proportion of total irrigation, as

reported in the EWC study. Similarly, there were a number of crops (melons, oil,

herbage and reed pond) listed in the EWC study that were not included in this study, they

have been included in “other” in Table 5.2 and water use was calculated again as a

proportion of the total irrigation reported in the EWC study

The livestock water use coefficients are from Brooks and Peter’s (1988) report - Water:

The Potential for Demand Management in Canada. The water use coefficients for

62

freshwater fish was calculated by adjusting the 1996 actual water used, as provided in the

1997 yearbook, to the 1997 fish output level. The proportion of loss is from the EWC

study.

Industrial

Freshwater use coefficients were calculated using water use figures and ton output figures

from the 1990 Tianjin yearbook. They were then adjusted to reflect an increase in

recycling levels, from 74% in 1990 to 77% in 1997, based on 1990 actuals as reported in

the 1990 yearbook and UNDP 2000 estimates. The proportion of loss is from the EWC

study.

Results

Table 5.3. presents the results of the modeling exercise with comparisons to the EWC and

UNDP’s estimates for water use in 2000. 1997 Water supply figures for Tianjin are also

provided in Table 5.4. A summary of results by sector follows:

Domestic 10000m3

Model 71,113EWC 69,000UNDP 85,625

Results among all three estimates are fairly similar. The difference with UNDP is mainly

because their estimates are for 2000, while the model’s are for 1997. While not shown

here, the Urban residential water supply matches the model’s estimates very closely. A

supply of 18,346 (10,000m3 ) was reported for 1997 while the model estimated a use of

19,939 (10,000m3 ).

Agriculture 10000m3

Irrigation 50% reliabilityModel 345,527EWC 240,700UNDP 127,500

Model results are very high. EWC estimates are based on fewer hectares of rice (1/2 of

actual) and vegetables (1/3 of actual) and more hectares of corn.

63

UNDP estimates also underestimate the hectares of vegetables (1/3 less than actual) but

more influential was that they chose a forecasting method that was based on lower crop

output and lower water usage rates to better reflect the water shortage situation.

Livestock 10000m3

Model 1,297EWC 4,700UNDP 4,511

Model water use results are very low. The model used Canadian coefficients, they need

to updated with Chinese coefficients. Some coefficients were provided by the UNDP

study but not for all animal categories.

Freshwater fish 10000m3

Model 31,453EWC 16,300UNDP 7,700

Model water use rates are very high, but since they are based on actual water use as

reported in the 1996 Tianjin yearbook they are probably the most accurate. The growth of

fish output has been very significant in the past few years, from 1990 to 1997 it doubled.

EWC estimated about one half of actual hectares of freshwater fish ponds while the

UNDP kept 1990 hectares and applied a much lower water use coefficient than EWC.

Industrial 10000m3

Model 97,877EWC 127,900UNDP 120,692

Model estimates are low. This is partly due to the 1997 model versus 2000 EWC and

UNDP estimates. Model estimates are based on actual industrial water use as reported

in the 1990 yearbook. These figures might be low. It is unclear if all self-supplied water

would be reported for the yearbook, especially within the growing sector of TVE’s,

which are much less regulated than SOE’s.

Total 10000m3

Model 554,638EWC 458,600

64

UNDP 346,028

The difference here is mostly due to differences in irrigation water use.

Total without agriculture10000m3

Model 173,475EWC 202,400UNDP 206,317Water supply 240,133

Water supply figures are shown in Table 5.4. Total figures from the 1998 Tianjin

yearbook do not include water used in agriculture. The total supply figure without

agriculture is greater than any water use estimate. There could be two main reasons why

the model estimates are below supply figures; the estimates of Domestic and Industrial

loss are too low and/or the estimates of industrial use are too low.

Water supply figures are also shown from the 1997 Urban Construction Statistics

Yearbook. These figures are for Tianjin’s urban areas only.

65

Table 5.2. Water demand estimation model - Tianjin 1997

water usewater use:Domestic population rate: litres/day annual annual

10,000 l/c/d 10,000 10,000 m3 10,000 m3Urban-Residential 462.95 118 54628 19939Urban-Infrastructure 462.95 130 60184 21967Rural 434.69 92 39991 14597

Environment % of urban0.197 8256

Loss % of total0.184 6355

Domestic total 71113

Agriculture Water use rates: Water use:low high low high

Irrigated land: hectares m3/hc/yr m3/hc/yr 10,000 m3 10,000 m3Rice 64942 7500 13500 48707 87672Wheat 150834 4000 4230 60334 63803Corn 151668 1200 2400 18200 36400Vegies 95748 11250 15000 107717 143622

Other % of total0.14 32894 46410

Orchards % of total0.29 77677 109593

Irrigation total 345527 487499

water use rates: water use:head l/hd/day m3/hd/yr 10,000 m3

Large 296419 61 22.27 660Pigs 1034000 9 3.29 340Sheep/Goats 450200 3 1.10 49Poultry 17005300 0.4 0.15 248Sub-total 1297

tons m3/tonFish 120557 2609 31453

Loss % of total0.225 7369

Agriculture total 385647 527619

Industrial Industrial Freshwater wateroutput use rate: use:

10,000 m3 tons 10,000 m3Food and Beverage 19.91 n.a. 5293Pulp and paper 40.56 167.99 6814Chemical 167.25 66.60 11139Petroleum 645.90 16.03 10351Machinery 2.80 3221.00 9019Ferrous metal 924.49 7.10 6568Textiles 21.71 564.62 12258Building materials 241.75 6.84 1654Electricity 166.53 22.20 3696

% of total (no food & beverage)Other 0.31 18796

% of totalLoss 0.184 12290Industrial total 97877

InstreamNavigation % of Urban 4484

0.107Total 559121 701093

66

Table 5.3. Water demand estimation model - Tianjin 1997ComparisonsAnnual water use in 10,000 m3

Model EWC UNDPDomestic 1997 2000 2000

Urban-Residential 19939 30600Urban-Infrastructure 21967 20600 55800Urban totalRural 14597 17800 17225

Environment 8256 12600

Loss 6355

Domestic total 71113 69000 85625

Agriculturelow low low

Rice 48707 29500EWC estimated 1/2 hectares of actual rice hectaresWheat 60334 59900Corn 18200 27400EWC estimated 68% more corn than actualVegies 107717 50200EWC estimated 1/3 of actual vegie hectares.

Other 32894 21200

UNDP estimated 32% fewer vegie hec.Orchards 77677 52500 and chose forecasting methodIrrigation total 345527 240700 127500based on lower water use and

lower returnsLivestock 1297 4700 4511

UNDP kept 1990 hectares and usedFish 31453 16300 7700a much lower water use rate than EWC

EWC estimated 1/2 the actual hectaresLoss 7369

Agriculture total 385647 261700 139711

IndustrialFood and Beverage 5293 9700Pulp and paper 6814 10800Chemical 11139 36100Petroleum 10351 18100Machinery 9019 19300Ferrous metal 6568 8300Textiles 12258 14900Building materials 1654 2600Electricity 3696 2600

Other 18796 5500

Loss 12290Industry total 97877 127900 120692

InstreamNavigation 4484 5500

Total 559121 464100 346028

Total without agriculture 173475 202400 206317

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Table 5.4. Water Supply - Tianjin

Annual water supply in 10,000 m3

Water SupplyUrban* Total**

Domestic 1997 1997Urban-Residential 18346Urban-Infrastructure 8488Rural

Environment

Loss

Domestic total

Agriculture

RiceWheatCornVegies

Other

OrchardsIrrigation total

Livestock

Fish

Loss

Agriculture total

IndustrialFood and BeveragePulp and paperChemicalPetroleumMachineryFerrous metalTextilesBuilding materialsElectricity

Other

LossIndustry total 42011

InstreamNavigation

Total

Total without agriculture 68845 240133

*Urban Construction Statistics Year Report** 1998 Tianjin Yearbook

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CHAPTER VI

CONCLUSION

Rapid population growth and increased water consumption by agriculture, industry and

the domestic sector are taxing the world’s fresh water resources. In some areas of the

world demand already exceeds supply. A growing number of countries will face water

shortages in the next 25 years, including Ethiopia, India, Kenya, Nigeria and Peru.

Large areas of China are already facing chronic water shortages. Water is essential to

life, health and economic development. Water resource management in these countries

must be given top priority. Water management has developed to mean more than simply

increasing supply to meet growing demand. It now includes finding technologies and

developing government policies to reduce the demand for water. While very difficult to

do accurately, forecasting future demand is indispensable to water management.

Forecasts help avoid water shortages, ensure economic growth, and avoid domestic and

international water use conflicts. They can also be used as management tools to explore

the impacts on water demand of future economic developments and to guide the adoption

of government policy to help reduce water consumption.

A water demand forecasting model attempts to relate trends in water demand with other

factors - social, economic and political, that will have an impact on water demand.

It is most useful at the river basin level, where supply and demand can be balanced. In

countries where little water data is available, a forecast method using water use

coefficients is most appropriate. Coefficients from other countries with similar levels of

economic development can be used if none are available for the country under study.

One of the major drawbacks of using forecasts in rapidly developing countries is that they

typically depend on historic trends, which might not be relevant. Alternatively, expert

advice on the most influential trends can be incorporated into the model. Depending on

the level of data available, accuracy can be further improved by disaggregating water use

by the main water using sectors – agriculture, industry and domestic use and by

determining supply and demand for each of the sub basins within the river basin. A

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model that tracks water supply and demand as water moves through the basin will help

prevent shortages for downstream users. Incorporating consumptive water use rather than

total water use data into the model would be most useful but that data is difficult to

obtain. As water availability and demand varies over time, the model must also

incorporate a seasonal component.

This paper began by presenting the framework of the water shortage situation in Northern

China. A situation that, according to World Bank estimates, will leave the Hai River

basin 20 billion cubic meters short of water by the year 2000. It then looked at the basic

components of water demand and the reasons and methods to estimate, forecast and

model water demand. An approach to water demand estimation for the basin was then

presented including a sample model for Tianjin and a list of water management options to

explore was provided.

The next step in the proposed model requires a great deal more data, by sector and by

subbasin. Except for Hebei province, where data is available by metropolitan area,

industrial output data is currently available only at the provincial level, making working

at the subbasin level impossible. Also, within the industrial sector some clarification is

needed as to whether the yearbooks are reporting the output of rural enterprises. Within

the domestic sector, type-of-household information is needed to make accurate estimates

regarding future residential water use. Among all sectors more data has to be collected to

make better estimates about the proportion of water that is “lost” to the system due to

leakage, consumption and pollution. The model will also require input from the other

3 X 3 university teams working on this project, especially the information on water

supply, pricing and technological approaches to water management, being collected by

the University of Toronto and Tsinghua University team. The running of the model, with

a variety of scenarios, should be useful to the team working on policy and institutional

framework (University of British Columbia and Peking University).

Greater involvement from a Chinese team of students will be necessary to move the

project forward. Future researchers on this project should be able to read Chinese,

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making library work much more efficient. Also, it was much harder for non-Chinese

students to get interviews and useful data from the various state agencies that were visited

in China.

If the above problems of data collection can be overcome the model for the entire basin

can be run and water management options tested. This would then lead to better

understanding of which policies should be proposed. However, without a powerful

regional planning authority it is unlikely that any solution to the problem will be adopted.

Since the reforms China has gone from a highly centralized to a highly decentralized

decision making system. To solve the water shortage problem a return to a more

centralized system is necessary. “The conflicts of interests among various departments

and regions as well as between central authorities and local governments are outstanding

and are difficult to be solved due to this weak unified management” (EVS Environment

Consultants 1997, 27).