Transcript WWRU and its impacts to water environments in Vietnam

WASTEWATER MANAGEMENT (WWM) AND ITS
IMPACTS TO WATER ENVIRONMENTS IN VIETNAM.
WWM CONCEPTS AND TECHNOLOGIES
Hanoi University of Civil Engineering,
1
Cities in Vietnam, classes I - V
Population, mln.
Urban population ratio in Vietnam
Total population,
m ln.
120
urban
population, m ln.
100
80
60
40
20
0
2000
2010
2020
Years
Years
Total population,
mln.
Urban population,
mln.
%
2000
2010
2020
76
93
103
15
30.4
46
20
33
45
2
Rapid urbanization and industrialization
Hanoi city: Population
 1945: 280,000
 1954: 380,000
 1960: 1,050,000
 2001: 1,700,000 among 2,750,000 total urban zone population
 2020: 2.5 million among 4.5 millions total urban zone population
 The area of Hanoi urban in 1994 was 4,600 ha, in 2000: 9,000
ha, and it will be up to 25,000 ha in 2020
Industrial ratio from GDP, %
400,000
200,000
36.0
1990
1995
1999
2000
Years
1999
2000
Years
Years
3
1994
1998
1992
1997
1990
1996
1988
0.0
1986
32.0
1.0
1984
1918
2.0
1982
0
34.0
3.0
1980
4.0
1978
5.0
38.0
600,000
1969
6.0
800,000
1954
7.0
Industrial ratio
from GDP, %
1,000,000
1939
8.0
40.0
1,200,000
1928
Agricultural ratio
from GDP, %
9.0
% GDP
% GDP
Agricultural ratio from GDP, %
Population, inh.
Hanoi inner-city population (4 districts), 1918 - 1994
Rapid urbanization and industrialization
 Urbanization and industrialization processes create
pressures on the environment and natural resources;
destroy the ecological balance, impact on environmental
quality and natural resources
 These pressures could exceed the “enduring ability” of the
environment and natural resources as well as the
“response ability”
4
Pressure-Status-Response (PSR) Model (Adopted from EPA)
Pressures
Pressures
Environment,
natural resources
Production,
Commerce,
Consumption
Environmental
status
Air, Water, Soil,
Natural resources,
Ecosystems,
Urban and rural areas
Energy, Transport,
Industries, Agriculture,
Forestry, etc.
Information
Information
Responses
Decisions,
Actions
Response
Responses
Decisions,
Actions
Legislations, Strategies,
Policies, New
technologies,
Pollution control,
Consumption change
Conventions, etc.
5
Water resources
Surface water resources:
 2360 rivers with lengths over 10 km accounting for a total
flow of 835 Billion m3
 Year 2000: 4700 m3 person yr-1
(global average: 7400 m3 person yr-1)
 Not equally distributed by locality or season:
- 5 months wet season: 75 - 80% of total flow
- 7 months dry season: 20 - 25% of total flow
6
Ground water:
 50 - 60 Billion m3 of total potential
 Maximum available for exploitation: 10 - 12 Billion m3
7
8
Hanoi water supply
Water supply in Hanoi city
Water demand, cmpd
1,200,000
1,000,000
800,000
600,000
400,000
200,000
0
2001
Ground water
2005
2020
Year
Surface water (Red river)
9
 Groundwater over-exploitation has caused depression and
subsidence phenomenon in some areas of Hanoi city
• The highest rate of subsidence (30 mm yr-1) has been
found in a 2-km2 radius surrounding Phap Van water
treatment plant
 Groundwater in Pleistocene (QII) aquifer has been slightly
polluted by nitrogen compounds, especially by ammonia,
which has being found at Ha Dinh, Tuong Mai and Phap
Van water treatment plants (up to 20 mg NH4-N l-1)
10
Domestic water use
 640 cities and towns with a population of 18 Million (23%)
 200 urban water supply projects, provide 2.7 Million m3 d-1 for
60% of the urban population this is equivalent to 60-80 l d-1
 40% of the urban population does not have access to an
adequate water supply
 90% urban areas are not equipped with adequate sewerage
systems
 1995: 28% population in rural areas served by clean water
 1999: 36%
 2002: 50% receiving 50 l d-1
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Water use for agriculture


1990: 47 Billion m3 (90% of total water consumption)
1999: 60 Billion m3 (85% of total)
12
Water use for industrial activities
 1990: 5.33 Billion m3 (9.8% of total water consumption)
 1999: 14 Billion m3 (15% of total)
13
Industrial wastewaters
 90% of industrial enterprises do not meet National effluent
standards
 73% of industrial enterprises do not have WW treatment
systems
 60% of WW treatment systems are not operated properly
14
Water quality of river basins
Red river delta: Organics pollution
 Domestic wastewater is a major pollution source, among
domestic, industrial and agricultural activities
Rivers in Central Vietnam:
 Affordable quality
 Lightly affected by salt intrusion due to tidal regime
Rivers in the Southern Vietnam:
 Increasing levels of organic and inorganic pollutants
 Sai Gon, Dong Nai, Thi Vai rivers, etc.
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16
Water environment problems
 Flooding
 Salt intrusion
 Pollution
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Monitoring data: 1995 - 2001
Variables Measured: Temp, pH, BOD5, COD, SS, TDS, EC,
DO,NH4+, NO3-, PO43-, Cl-, Fe, Pb, Cd, (Cr, Hg, As), Coliform.
 BOD5 , COD, NH+4, NO-3 are generally 2 – 4 times higher
than the permissible value
 Total coli-form is 100 times higher than the permissible
value
 In some places Pb and Hg concentrations were several
times higher than permissible value
 Some rivers are effectively drainage channels
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Pollution of surface water has increasd
NH4, mg/l
BOD5, mg/l
150.00
100.00
50.00
25.00
20.00
15.00
10.00
5.00
0.00
0.00
1995 1996 1997 1998 1999 2000 2001
To Lich River, at New Bridge
Kim Nguu River, at Yen So Gate
Years
1995 1996 1997 1998 1999 2000 2001
To Lich River, at New Bridge
Kim Nguu River, at Yen So Gate
Years
19
Wastewater re-use in agriculture
20
Untreated faecal sludge use in aquaculture
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Pesticides






Before 1985:
0.3 kg ha-1
1986 – 1990:
0.4 – 0.5 kg ha-1
1995:
0.85 kg ha-1
1999 - 2000:
1.12 kg ha-1
Concentrated in Red and Mekong River deltas
Improper use
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Fertilizer
 5 Million t yr-1 inorganic fertilizers including 3 Million t yr-1 of
imported fertilizers
 Vietnam: 80-90 kg inorganic fertilizer ha (Rice = 100 - 110 kg
ha-1)
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Mitigation measures





Legislative base, economical tools
Environmental standards
Urban planning and management
Pollution control technologies
Education and public awareness
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Standards
 Water quality
TCVN 5942:1995
TCVN 5943:1995
TCVN 5944:1995
 Discharges
TCVN 5945:1995
TCVN 6773:2000
TCVN 6980:2001
TCVN 6982:2001
TCVN 6984:2001
TCVN 6986:2001
 Reuse: (WHO)
Stepwise approach!
TCVN 6772:2000
TCVN 6774:2000
TCVN 6981:2001
TCVN 6983:2001
TCVN 6985:2001
TCVN 6987:2001
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“Critical Control Points” as barriers
against disease transmission
Person-toperson
Dishes
Dom. animals,
rodents
Pathogens in
faeces
Flies
Food
Soil
Fish
Water
Containment,
treatment
26
Barriers:
improved excreta disposal, hygiene and waste management
Planning
 DEWATS concepts vs centralized WW systems
IC’s: “Flush-and-Discharge”
(all mixed)
Facets
27
RURBIFARM Project
Sustainable Farming at the rural-urban interface.
Introduction to the NISF research sites in Hanoi,
Vietnam
by NISF team
What is peri-urban agriculture?
1.
2.
3.
Geographically close to cities.
Agricultural production mainly for city use.
City activities have a direct impact on rural
activities.
Two proposed NISF study sites:
Tien Phong & Minh Khai Commune
Hanoi meteorological 2000 (Lang station)
Rainfall
Evaporation
300
35
Temperature
30
250
mm
20
150
15
100
oC
25
200
10
50
5
0
0
1
2
3
4
5
6
7
8
9
10
11
12
month
Inorganic fertilizers pressure in a ha of agricultural land in Vietnam from 1996 - 2000
Year
N
P2O5
K2O
Total
Agricultural land
(1000 ha)
1996
1997
1998
1999
2000
109.4 103.2 107.9 106.3 113.6
51.8
43.4
49.5
59.9
54.7
9.1
22.7
24.7
43.9
22.6
184.6 169.3 182.0 210.1 190.8
7681.2 7843.1 8080.2 8712.8 9345.3
Organic fertilizers pressure in a ha of agricultural land in Vietnam from 1996 - 2000
Year 1996
1997
1998
1999
2000
N
43.2
43.4
42.9
40.8
39.2
P2O5
48.9
49.5
49.2
47.1
46.1
K2O
105.3 105.4 104.2
98.7
94.0
Total
197.4 198.3 196.2 186.6 197.4
Agricultural land 7681.2 7843.1 8080.2 8712.8 9345.3
(1000 ha)
Tien
Phong
site
Minh
Khai site
Overview of
Hanoi city and
the study area
Degraded land
(Acrisols)
Tien Phong
commune/A
CIAR
Minh Khai
commune
Fertile soil
(Fluvisols)
Minh Khai site
(vegetable-FS)
ACIAR/Tien Phong site
(mixed FS)
Land preparation for vegetable planting
Irrigation work