Challenges of Ecological Sanitation: Experiences from Vietnam and Malawi
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Transcript of Challenges of Ecological Sanitation: Experiences from Vietnam and Malawi
Challenges of Ecological Sanitation:
Experiences from Vietnam & Malawi
H. Harada1*, S. Matsui1, S. Fujii1, S. Ono2
1 Graduate School of Global Environmental Studies, Kyoto Univ.2 Nippon International Cooperation for Community Development
Challenges of global sanitation (MDGs) Diarrhea, a result of poor sanitation, is the 6th death cause and the 7th global burden of diseases.
1.7 & 0.6 bill ion w/o proper sanitation in Asia & Africa
INTRODUCTION
Global water crisis Food security and depletion of phosphate rock
Dry toilet with excreta use for agriculture
(Ecological Sanitation)
2/14An ecosan toilet
Ecosan still challenging in its broader implementation
INTRODUCTION (Cont’d)
Based on 3 ecosan cases in Vietnam & Malawi, this study examined possibilities & challenges of ecosan from 3 aspects above.
Two essential requirements to provide comfortable defecation space to be
continuously accepted to reduce health risk by a dry toilet
to use urien and humanure for agricultureAnother requirements of ecosan toilets
Purpose:
• Urine as liquid fertil izer• Feces as humanure after deposition with ash for sanitization
3/14
Humanure
Urine
Fecophobic attitude
Case B: An ecosan introduction in southern Vietnam
METHODOLOGY
Case A: A traditional ecosan in northern Vietnam
Case C: A large‐scale ecosan introduction in Malawi
At a village with traditional custom of ecological sanitationA quantitative microbial risk assessment on excreta use
A survey on comfort and acceptance after long‐term use
At a village w/o excreta use custom, where household daily practices were monitored in details
Similar in the ecosan design of Case B, but more successful in excreta use fro agriculture
A comparison of cases B and C for extracting essential components for grater success 4/14
Trai hamlet, Phu Xuyen, Hanoi, Vietnam Dry toilet (56%), WC (44%)WC toilet wastewater discharged to the env.
CASE A: TRADITIONAL ECOSAN
soil
Irrigation
water
foods
hands
?
?
?
?excreta
Health risk assessment (E. Coli base)
More contamination and health risk due to dry toilet and excreta use?
Urine
Fecal hole
5/14
?
Traditional ecosan toiletFig. Potential pathway of fecal pathogens
TRADITIONAL ECOSAN:HEALTH RISK?
E. Coli cou
nt
(CFU
/100
mL, CFU
/device, CFU
/hand)
1
10
102
103
104
105
106
n=20 n=6Boiled‐and‐stored rain water
(Drinking)
Ecosan WCn=19 n=5
Stored rain water(hygiene)
Ecosan WCn=22 n=7
Storedwell water(bathing)
Ecosan WCn=19 n=6
Chopstick
Ecosan WCn=19 n=5
Rice bowl
Ecosan WCn=34 n=10
Hand
Ecosan WC
IN-HOUSE CONTAMINATION STATUS
No significant effect of excreta‐use custom on in‐house contamination level
Fig. Comparison of in‐house contamination statusbetween ecosan tolet users and water‐flush‐toilet uses
Ecosan: Ecosan toilet usersWC: Water flush toilet users
6/14
10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101
Paddy field soil during farmingBoiled-and-stored rain water during drinking
Stored well water during bathingStored rain water during hygiene practices
Devices of eating during eatingGarden soil during gardening
Pond water during fishingIrrigation water during irrigation
River water during fishing in a riverPond water during swimming in a pond
Total
TRADITIONAL ECOSAN:HEALTH RISK?
HEALTH RISK FROM FECAL CONTAMINATION
Infectious risk (event/cap/year)
0.59 – 2.7 infectious event/cap/yr (95%tile, Med.=1.4)
• Large health risk but maily from environmental water• Dry sanitation has a great advantage to reduce health risk by avoiding toilet wastewater discharge to the water environment
Fig. Infectious risk contribution though various daily activities
Potential pathw
ay
to transm
it fecal infectio
us dise
ass
7/14
10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101
Infectious risk (event/cap/year)Fig. Infectious risk contribution though various daily activities
10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101
Paddy field soil during farmingBoiled-and-stored rain water during drinking
Stored well water during bathingStored rain water during hygiene practices
Devices of eating during eatingGarden soil during gardening
Pond water during fishingIrrigation water during irrigation
River water during fishing in a riverPond water during swimming in a pond
Total
TRADITIONAL ECOSAN:HEALTH RISK?
HEALTH RISK FROM FECAL CONTAMINATION
Infectious risk (event/cap/year)
• Large health risk but maily from environmental water• Dry sanitation has a great advantage to reduce health risk by avoiding toilet wastewater discharge to the water environment
Fig. Infectious risk contribution though various daily activities
Potential pathw
ay
to transm
it fecal infectio
us dise
ases
8/14
CASE B: ECOSAN INTRODUCTION IN A VILLAGE, VIETNAM
Urine container
Two faecal chambers
Ventilation pipe
Hamlet No.5, DP, Lamdong, Vietnam A minority hamlet w/o toilets and custom of excreta use
80% infected by parasites
85 toilets introduced(80 USD/unit, 2002‐03)
Fecal holes
Urinal
9/14Double vaults urine diversion toilet
Urine diversion squatting pans
ECOSAN INTRO. IN A VILLAGE:ACCEPTABILITY? (Cont’d)
SITUATION AFTER 39 MONTHS
Check itemDuring Month 0‐4 At Month 39
(%)(n=80)
(%)(n=50)
Offensive fecal smell inside a toilet 1.3 14.0
Maggots inside a toilet vault 0 12.0
Many flies inside a toilet vault (>10 flies) 0 0.0
Table Conditions of ecosan toilets after 39 months
10/14
ECOSAN INTRO. IN A VILLAGE:ACCEPTABILITY? (Cont’d)
EXCRETA USE FOR AGRICULTURE
Check item At Month 39% of toilets n
Feces never taken out from vaults 63.3 30 Feces taken out of vaults before a proper retention period 33.3 12
Feces never used for agriculture 58.8 17 Urine not used for agriculture properly 65.4 26
Table Use of feces and urine
The toilet itself was accepted widely but agricultural use of excreta was a great challenge.
11/14Collected urine Deposited feces with ash
A comprehensive development project since 2007, after our ecosan in Vietnam
In three districts of Malawi, 783 ecosantoilets introduced. Local bricks from local people: cement and corrugated iron sheets from NICCO
Basically similar design of the ecosan in Vietnam, but one of successful projects in the areas without any custom of excreta use
CASE C: SUCCESSFUL LARGE-SCALE ECOSAN IN MALAWI
12/14Feces taken out from a toiletUrine diversion squatting pans
Double vault urine diversion toilet
COMPONENTS FOR LARGE-SCALE SUCCESS?
- Moringa and Jatrophaplanted
- Fruit trees planted
- Organic farming - Distribution of local seeds
- Measures of pests and insects
- Distribution ofmosquito nets
- Health education
- Toilet construction- Feces&urine as organic
fertilizer
- Hand Pumps- Workshop for village level operation & maintenance
- Fostering local leaders - Committee development for agriculture, women,
and health
Reforestation
Human Resource Development
Water Supply Ecosan toilet
-
Measures forinfection
Grain storage
Agriculture
ComprehensiveRural
Development
COMPREHENSIVENESS
13/14
How to properly use urine & feces as the important lesson from Vietnam
Farmers with confidence on better yield of maize, resulting in better health conditions
Integration of ecosan with agriculture, and demonstration of the increase in agriculture products=>“demands of urine and humanure created.”
Better operation of toilets, better performance to improve health situation
INTEGRATION WITH AGRICULTURE
COMPONENTS FOR LARGE-SCALE SUCCESS? (cont’d)
14/14
Humanure
Application of humanure
Demonstration of urine and humanure use
Health risk on ecosan toilet use Great advantages to reduce health risk by avoiding toilet‐wastes discharge to the water environment
Acceptance of ecosan toilets Confirmed at a long‐term base with comfortable room for excretion. However, excreta use not executed largely.
An essential component for grater implementation Integration of ecosan with strong support to agriculture production, resulting in demand creation to treat and reuse human excreta
CONCLUSIONS
Ecosan would contribute to sanitary improvement and food security. There is still a challenge of excreta use but its integration with agricultural production shall be a promising approach.
15/14
Thank you for your kind attention.
This study was supported by JSPS KAKENHI 06J03015, 21860049, 10135535 and 25870377; and the Kyoto University Global COE project “Global Center for Education and Research on Human Security Engineering for Asian Megacities”. The authors also appreciate contributions to the field investigation of Dr. Nguyen Pham Hong Lien, Ms. Pham Hong Giang, Mr. Kuroda Masataka and Mr. Ryo Sakaguchi.
16/14
PARASITE CONCERNS
0
20
40
60
80
100
150 200 250 300Ratio
of infectio
uparasite eggs (%
)
Retention time in a toilet chamber (day)
ControlExperimental
Fig. Sanitization performance of the toilet17/14