current status of water-related … files/s7-pham...college of sciences, hue university, vietnam...

ICSS Asia 2012, Bali, Indonesia

Pham Khac Lieu, D.Eng.

Department of Environmental Science

College of Sciences, Hue University, Vietnam

CURRENT STATUS OF

WATER-RELATED

SANITATION CONDITIONS IN

HUE CITY, VIETNAM


Contents

1. Hue city at a glance

2. Water resources and supply in Hue

3. Water-related sanitation practices in Hue

4. Threats to water-related sanitation improvement

5. Concluding remarks


• Coordinates: E 107o31’45’’-107o38‘, N 16o30’45’’-16o24'

HUE CITY

We are here.

1. Hue City at a glance



Hue City

• Area: 71 km2

• Population: 339,000 (2010)

• Ancient capital of Vietnam

(18th~first-half 20th centuries)

• A World Cultural Heritage

(since 1993 by UNESCO)

• Famous destination for

tourists, a “festival city” of

Vietnam

The Citadel

The King’s Tomb



Land use (2010 data)

Agriculture

22.5%

Forestry

5.4%

Specially

used

41.2%

Residential

29.1%

Unused

1.8%

Economic activities (2009 data)

Industry &

construction

28.5%

Services &

tourism

70.2%

Agro-

forestry

1.3%

(Source: Hue City’s Statistical yearbook, 2010, 2011)



Geographical features

• flat land of the downstream basin of the Huong River

• rather low elevation

Climate

• hot and wet

• average annual temperature: 25oC

• average annual rainfall: 2,500 mm

Hue

City



• Plentiful water resources • Surface water is major:

– Huong river and its branches

– Lakes and canal system

Huong River • catchment area: 2,830 km2

• average flow: 160 m3/s

• lowest flow: 25 m3/min

• irregular flow distribution: 70 -75% of annual quantity in Oct.- Dec.



Water quality

• Mainstream of Huong river

– Generally good for domestic supply, irrigation, recreation, etc.

– Slightly organic and pathogenic pollution (in dry season)

– Highly turbid (in flood season)

• River’s branches, lakes and canal

– Moderate organic pollution and eutrophication (dry season)



Huong river water is

clear in dry season

but becomes

highly turbid in

rainy season.



Sample pH DO,

mg/L

COD,

mg/L

BOD5,

mg/L

SS,

mg/L

NO3-N,

mg/L

NH4-N,

mg/L

PO4-P,

mg/L

RW1 6.6 7.7 9.7 2.5 14.1 0.3 0.1 0.1

RW2 7.2 7.0 20.5 1.3 23.0 1.0 0.3 0.1

RW3 7.1 6.6 18.0 2.5 18.1 0.8 0.1 0.1

RW4 6.9 5.7 10.5 3.8 12.7 1.8 4.2 0.0

RW5 7.2 5.7 7.6 3.2 10.2 1.2 2.1 0.0

Average 7.0 6.5 13.3 2.6 15.6 1.0 1.3 0.1

National

regulation*

A1 6 -

8.5

6.0 10 4 20 2 0.1 0.1

A2 5.0 15 6 30 5 0.2 0.2

*National Technical Regulation for Surface Water Quality (QCVN 08:2008/BTNMT):

A1-applied for surface water able to use for domestic supply without treatment.

A2-applied for surface water able to use for domestic supply with appropriate treatment

Example: Water quality of Huong river and branches in 2010-2011 (our

monitoring data)



Water use in Hue city

• Public piped water is

main use

• Tap water coverage:

100% city area

(HUEWACO, 2010)

• Average per capita

consumption: 120 -

140 liters/day

97%

1% 2%

Public piped water Drilled wells Dug wells

Distribution of domestic water use by

households (Center for Preventive Medicine,

2010)


Water supply by HUEWACO (Water Supply & Construction Co.Ltd.)

• 16 plants with total capacity of 142,000m3/d for the whole province

• 3 plants located in Hue city with 114,500 m3/d

Quang Te 1 Plant: 20,000m3/d

Quang Te 2 Plant: 82,500m3/d

Da Vien Plant: 12,000 m3/d



Tap water quality

• Meets all requirements by National Technical Regulation on Drinking Water Quality

• Turbidity always 10 times lower than standard value (0.2 NTU vs. 2.0 NTU)

• Declared Water Safety Plan in 2008 (one of three companies in South-East Asia recognized by WHO)

Water tariff in Hue:

Basic price + VAT + WW fee + PES

4,100 VND + 410 VND + 40 VND

= 4,550 VND/m3 (0.22 USD/m3)

(PES: Payments for Forest Services)



3. Wastewater management in Hue

Wastewater generation

• Domestic wastewater is major, industrial

wastewater in minor – Domestic WW: 32,400 m3/d

– Industrial WW: 2,000 m3/d (our estimation, 2009)

Urban sewerage network • Coverage: only 30% (population based), 35 -

40% (area based)

• Combined system (both storm water and WW)



Domestic wastewater characteristics

Parameter 1997 2005 2006-

2007

2010-

2011

National

regulation

COD, mg/L 170 223 298 181 N.A

BOD5, mg/L 115 151 213 86 30

SS, mg/L 77 113 155 37 50

T-N, mg/L 25 15 20.9 29 30 (NO3-N)

T-P, mg/L 11 9 1.7 3 6

Data source Hop et al.,

1997

HEPCO,

2007

HEPCO,

2007 Our survey

QCVN

14:2008/

BTNMT

Domestic WW in Hue is not so strongly polluted in terms of organic and nutrient contents.



Domestic wastewater

• At present – No collection system and

treatment plant in Hue

– Discharged into environment

(rivers, lakes,…) with some

pretreatment or without

treatment.

• On going project “Hue City Water Environment Improvement” (loaned from Japan)

1st phase (2008-2016): construction of a MWWTP with capacity of 20,000 m3/d.

(HEPCO, 2007; Thua Thien Hue PPC, 2009).



4.1. Household sanitation practices

97.895.2

2.24.8

95.096.4

5.03.6

0

20

40

60

80

100

2009 2011

%

Having acccess to toilet Not having access to toilet

Sanitary toilets Unsanitary toilets

Data source: Provincial Center for Preventive Medicine, 2010, 2011

Average data on household sanitation practices in Hue city.



Data on access to toilet by wards in 2011.

Data source: Provincial Center for Preventive Medicine

0%

20%

40%

60%

80%

100%

Phu

Binh

Kim

Lon

g

Huo

ng L

ong

Phu

Thu

an

Thuan

Hoa

Thuan

Tha

nh

Thuan

Loc

An

Hoa

Huo

ng S

o

Tay L

oc

Phu

Hoa

Phu

Hie

p

Phu

Hau

Phu

Cat

Vy Da

Xua

n Phu

Phu

Hoi

Phu

Nhu

an

Vinh

Ninh

An

Cuu

An

Don

g

An

Tay

Phu

ong

Duc

Phu

oc V

inh

Truon

g An

Thuy Xua

n

Thuy Bieu

Wards

Sanitary toilets Unsanitary toilets Not having access to toilet



On-site treatment facilities (% of total households)

Treatment facilities 2006 2009 2011

Septic tank 80.4 86.7 87.1

Cesspool (seepage pit) 5.3 4.5 3.6

Double vault latrine 2.5 2.6 3.8

Ventilated pit latrine 0.7 0.8 1.2

Others 4.1 0.6 2.1

Sum (having access to toilet) 92.9 95.2 97.8

Data source: Provincial Center for Preventive Medicine, 2011



Cistern flush toilet with septic tank

Excretion Cistern

flush toilet Septic tank

3 - 6 L water

Suction

truck

Waste landfill

site

Single mode:

6 L/flush

Double mode:

6 L/big flush

3 L/small flush



Pour flush toilet with septic tank

Excretion Pour flush

toilet Septic tank

~ 3 L water

Suction

truck

Waste landfill

site



• Discharge ways of septic tank’s effluent (or black water):

46%

16%

38%

Directly into

surrounding river,

pond, canal, etc To the public sewer

after a soak pit

Mixed

with

grey

water

Soak

pit

To public

sewer

Black

water

Soil percolation

after a soak pit

Source: Our survey data, 2011



4.2. Personal hygienic practices

• Hand washing: – 68% always and 32%

occasionally wash hands before eating.

– 83.5% always and 16.5% occasionally wash hand after defecation.

• Anal cleaning: – Paper use: 59.3%

– Both paper and water use: 32,2%

– Water use: 8,5%

Tissue paper Water for anal cleaning



4. Water-related sanitation facilities in Hue

Poor sanitation practices in the slum at Phu Binh ward:

• 115 households with 783 persons

• only 12 public toilets

• located closely to outer canal of Citadel




Waterborne diseases in Hue city (2009 – 2011)

(cases of patient)

Disease 2009 2010 2011

Cholera 0 0 0

Typhoid 1 1 0

Dysentery 320 4 345

Diarrhea 2812 3504 1713

(Source: Provincial Center for Preventive Medicine, 2010)

No outbreak in recent years


5. Threats to sanitation improvement in Hue

Strengths Weaknesses

• City size is not too big

• Plentiful water resources and

good water supply system

• Land availability for improvement

• Special concerns of local

government

• Lack of financial & skilled human

resources

• Lack of waste control technology

• Lack of an integrated plan

• Low participation of stakeholders

Opportunities Threats

• People’s income increases

• International cooperation and

ODA

• Low altitude

• Complicated weather and natural

disasters in the city

• Effects of upstream works

• Future expansion of the city

• Climate change

SWOT analysis of water-related sanitation in Hue



Example: Flooding

• Huong river: unequal distribution of flow (> 70% annual flow in 4 months of rainy season flood often occurs

• Increase in health risk during flood

The historical flood in 1999 A heavy flood in 2007


Some pictures of the flood on 5 November 2011



Example: Upstream dams and reservoirs - possible impacts: – Changes in flooding regime/duration

– Changes in water quality

Ta Trach Reservoir • Dam height = 56 m

• Dam length = 1,112m

• Storage capacity = 646 Mm3

Binh Dien Dam • Dam height = 83.6 m

• Dam length = 362.8m


Huong Dien Reservoir • Dam height = 82.5 m

• Dam length = 180 m


increase health risk


Concluding remarks

• Current status of water-related sanitation in

Hue city: – Good water supply practice: plentiful source, reliable

supply system, safe water planning, etc.

– Inadequate drainage and sewerage system: low

coverage, no sewage treatment, etc.

– Good basic household sanitation but some problems

remained: • Uncontrolled discharge of septic tank’s effluent?

• Weak linkage between household and public sanitation systems.

– Not good personal hygienic practices: low awareness of

a significant number of people

– Some threats to the improvement of sanitation in Hue


Expectations

• Expectations for collaboration from the International Network on Health Risk Assessment in Urban Area? – Baseline and comprehensive data on water-

related sanitation conditions; – Analysis of constraints and factors of

sanitation improvement; – Health risk assessment under inundation

condition; – Planning and solutions for a sustainable

sanitation system; – etc.

current status of water-related … files/s7-pham...college of sciences, hue university, vietnam...

Documents