Design and Implementation of the
KanchanTM Arsenic Filter
in the Nepal Terai
The World Bank
Brown Bag Lunch
October 19, 2004
Susan Murcott
Dept. of Civil and Environmental
Engineering
Massachusetts Institute of Technology
20th century Western engineering design was
comparatively simple
 Technical Criteria
Technical
 Economic/Financial
Criteria (Cost-Benefit
Analysis)
Financial
Environmental Awareness Added another Dimension
 Technical
Technical
 Economic/Financial
Criteria (Cost-Benefit
Analysis)
 Environmental
Financial
Environmental
“Sustainable development” has 2 widely
accepted meanings:
Balance: economic, social,
environmental aspects
Equity…”meeting the needs of the present
without compromising the ability of future
generations to meet their own needs.”
- Our Common Future, 1987
“Engineering design for sustainable
development” framework
Financial /Economic
* Low cost
* Supports local economies
* Self-sustaining
Technical
•Water quality evaluations
•WHO Guidelines
•National Standards
• Flow rate
• Use local materials
Social
• Socially acceptable
• Simple/user friendly
• Convenient
• Durable
The Design Process
(text book version)





Information Gathering
Problem Definition
Idea Generation
Concept Evaluation
Lab Research, Experimentation &
Analysis
 Detail Design
 Fabrication
 Testing & Evaluation (Lab and
Field)
Co-Designing/Co-evolving for Development
(an iterative process)
1. Problem Awareness
Co(m)-passion, and Partnership
10. Reiteration
2. Problem CoDefinition
9 Scale-up
8. Implementation
7. Pilot studies
Co-designing/
co-evolving
equitable and
sustainable
development
3. Idea CoGeneration
4. Concept
Co-Evaluation
6. Refined Design
(Field and lab testing,
5. Field Experience,
multiple sites,
Fabrication,
multiple countries)
Experiment, Lab Work,
Analysis
1. Problem Awareness,
Co(m)-passion, Partnership
Problem Awarensss
Where is Nepal?
Where is Arsenic in Nepal?
(NASC and ENPHO, 2004)
Field Project Sites
Kathmandu
Kapilvastu
District
Rupandehi
District
Nawalparasi
District
Parsa & Bara
Districts
Rautahat
District
Passion
Co(m)-passion
Partnership
Environment and Public Health
Organization (ENPHO)
Rural Water Supply and Sanitation
Support Programme (RWSSSP)
2. Problem Co-Definition
Problem Co-Definition
•Our proposal is to design a household drinking water treatment
unit to remove arsenic and pathogens;
•Technical Performance: Remove arsenic, bacteria and parasites
to National Standards or WHO Guidelines;
• Water Quantity: The flow rate should be > 10 L/hour;
• Cost: The cost/unit should be < $30. Yearly replacement parts
<$2, designed for use by individuals in rural areas and urban
slums who earn <$2/day;
• Manufacturing: To be produced by local people, using locally
available materials, creating local jobs;
• Socially acceptable: ease of use and maintainence by women
Problem Co-Definition
Arsenic Technology Database
Gather information for 50+ technologies:
• Arsenic removal mechanisms (physical, chemical, etc)
• Technical performance
• Construction, operation and maintenance
• Cost
• Flow rate
• Strengths, weakness, limitations
http://web.mit.edu/murcott/www/arsenic
Idea Co-Generation
8 Arsenic Removal Technologies
 (1) 3 Kolshi (in Nepali = 3 Gagri with zero valent iron
filings);
 (2) Iron filings in jerry can;
 (3) Coagulation/Filtration (2-Kolshi based on
Chakraborti’s arsenic removal system);
 (4) Iron oxide coated sand;
 (5) Activated alumina metal oxide #1 (Apyron Inc.);
 (6) Activated alumina metal oxide #2 (Aquatic Treatment
Systems Inc.);
 (7) Arsenic treatment plant;
 (8) Arsenic Biosand Filter
Three-Kolshi (Gagri) System
Raw water
Iron
filings
Fine
sand
Filtered
water
Jerry Can
1. Fill 10 L plastic jug
with raw water.
2. Add iron
filings
3. Wait 3 hours
4. Decant treated
water
Coagulation/Filtration (2-Kolshi)
Chemical packet
Raw Water
Treated
Water
Mixing & Settling
Filtration
Iron Oxide Coated Sand (IOCS)
Raw Water
Sand and gravel
Iron Oxide Coated
Sand (IOCS)
Treated Water
Activated Alumina Metal Oxide #1
(Apyron Aqua-Bind Media)
Raw Water
Sand
Influent
Activated
Alumina
GAC
Treated Water
Effluent
Activated Alumina Metal Oxide #2
(Aquatic Treatment Systems, Inc.)
Raw Water
Alumina Manganese
Oxide (A/M)
Treated
Water
Arsenic Treatment Plants (ATPs)
Aeration
Chamber
Storage
Treated Water
Sand
Filter
KanchanTM Arsenic Filter (KAF)
Field Experience, Fabrication, Experiment, Lab
Engagement with:
• local people and
partners,
• local environment
• the problem and
solutions
Stages 5-8 in Arsenic Mitigation
1999 2000 2001 2002 2003 2004 2005+
Field Experience,
Fabrication,
Experiment,
Lab Work , Analysis
Refined Design
Pilot Studies (Phase I)
Pilot Studies (Phase II)
Implementation
Refined Design
Phase I Evaluation
Phase I Evaluation
1. Preliminary screening of technologies in database/
website.
2. Select 8 technologies to be field tested against
following criteria:
Technical Performance:
Meet National (50 ug/L) or WHO guidelines
(ug/L)) for arsenic and microbial removal.
Flow rate > 10 L/hour
Social:
Customer satisfaction, specifically among
women who are typically the managers of
household water.
Financial:
Affordable to people earning $1/day
Phase I Evaluation Summary
Technology
3-Kolshi
Jerry Can
Iron Coated Sand
Alumina #1
Alumina #2
2-Kolshi
Treatment Plants
KAF
Technical
Social
Cost
Recommend
for Phase II?
Pilot Studies
Phase II Evaluation
Phase II Pilot Studies of 3 Technologies
3 Kolshi
Coagulation/
filtration
System
(2-Kolshi)
KanshanTM
Arsenic
Filter (KAF)
Phase II Evaluation Summary
Arsenic removal
Iron removal
Flow rate
3-Kolshi
2-Kolshi
AKF
95-99%
80-90%
90-95%
Not tested
Not tested
93-99%
3-5L/hr
1-5L/hr
10-30L/hr
2nd
3rd
Best
Materials availability
Easy construction
Simple O&M
Long-term sustainability
User acceptance
Low initial cost
Low running cost
Overall Ranking
= poor
= moderate
= good
KAF Pilot Study Results (n=16)
Technical
Indicators
Average
Results
Arsenic Removal
93 %
Total Coliform
Removal
E. Coli Removal
58 %
Iron Removal
93 %
Flow Rate
14 L/hr
64 %
Stages 5-8
KanshanTM Arsenic Filter
(AKF)
KanchanTM Arsenic Filter
• Developed in Nepal and at MIT based
on improvement of slow sand filter
• Intended for arsenic and bacteria
removal
• Constructed with easily available local
materials
• Manufactured by trained local
technicians
• Adequate flow rate for a large family
(15L/hr)
• No chemical additives
• No replacement parts except iron nails
• Easy to operate and clean
KanshanTM Arsenic Filter Cross Section
Diffuser Basin
Lid
Brick chips
Container
Iron Nails
Water
Fine Sand
Pipe
Coarse Sand
Gravel
Filter Operation
1. Pour water into top basin.
Water will pass through
filter and flow up the pipe
2. Collect filtered water at the
pipe outlet
3. If flow rate is insufficient,
then cleaning is required
Filter Cleaning/ Maintenance
Wash your hands with soap
Remove diffuser basin
Stir the uppermost ½ inch of
sand with your fingers
Filter Cleaning/ Maintenance
Remove turbid water with a cup.
Replace the basin and add more water.
Repeat this process three times total
Discard the turbid water in a dug hole
with some cow dung in it
Now the filter can be used again
Further Work – Refined Design
Concrete
Square
(2002)
Concrete
Round
(2003)
Plastic
Hilltake
(2003)
Plastic
Gem505
(2004)
Technical Performance
• Currently more than 1000 filters
are in operation. 2000 by Jan.05
• More than 500 were sold by NRCS,
about 100 by Fund Board, about 450
by RWSSSP
• Filters were sold starting from
September 2002 until today
• We have monitored 800+ filters
between February to May 2004 on
arsenic and iron removal
• The average time between filter
installation date and filter
monitoring date is 93 days
KAF Blanket Monitoring
Arsenic Removal (n=644)
0 to 10
11 to 50
51 to 100
101 to 250
250 +
Influent Arsenic
Concentration (ppb)
Effluent Arsenic
Concentration (ppb)
KAF Blanket Monitoring
Arsenic Removal (n=644)
Influent Arsenic Concentration (ppb)
Effluent Arsenic Concentration (ppb)
500 450 400 350 300 250 200 150 100
500
0
0
0
0
0
0
0
0
0
450
3
1
1
1
0
0
0
1
400
1
0
0
1
0
1
0
350
0
0
0
0
0
0
300
0
1
0
0
0
250
2
1
0
0
200
2
0
1
150
1
0
100
0
90
80
70
60
Unacceptable
50
Acceptable
40
30
20
Figure indicates
10
number of filters
ND
90
0
0
0
0
0
0
0
0
0
1
80
0
0
0
0
0
1
1
0
0
0
0
70
0
0
0
0
0
0
0
0
1
2
0
0
60
0
0
0
0
0
0
0
0
0
1
0
0
0
50
0
0
0
0
0
2
0
0
0
0
0
0
0
0
40
1
0
2
1
1
2
0
1
1
0
0
0
1
0
0
30
0
3
1
3
1
2
0
0
1
0
1
1
2
0
0
0
20
0
2
2
1
3
1
0
1
3
3
0
0
5
1
0
0
0
10 ND
2
5
1
8
2
7
3 14
1 17
1 23
1 23
1 14
8 76
6 53
1 43
2 36
13 29
3 49
2 15
0 14
0 19
0 10
68
Filter Performance: Arsenic (n=650)
Distribution of Arsenic Influent and Effluent Concentrations
100.0%
90.0%
80.0%
Influent
% of all filters
70.0%
Effluent
60.0%
50.0%
40.0%
30.0%
20.0%
10.0%
0.0%
0 to 10
11 to 50
51 to 100
101 to 250
Arsenic Concentrations (ppb)
250 +
1.5 Years Arsenic Monitoring on Filter A
(Nim Narayan Chaudhary)
100
90
Arsenic Concentration (ppb)
80
70
Raw Water
60
Treated Water
50
40
30
20
10
0
Time
1.5 Years Arsenic Monitoring on Filter B
(Lila Bdr. Pun)
300
Raw Water
Arsenic Concentration (ppb)
250
Treated Water
200
150
100
50
0
Time
ct
-0
2
-0
2
N
ov
-0
D 2
ec
-0
2
Ja
n0
Fe 3
b0
M 3
ar
-0
3
Ap
r0
M 3
ay
-0
3
Ju
n03
Ju
l-0
Au 3
g0
Se 3
p03
O
ct
-0
N 3
ov
-0
D 3
ec
-0
3
Ja
n0
Fe 4
b0
M 4
ar
-0
4
Ap
r0
M 4
ay
-0
4
Ju
n04
O
Se
p
Arsenic Concentration (ppb)
1.5 Year Arsenic Monitoring on Filter C
(Bhanu Primary School)
450
400
350
300
250
Raw Water
Treated Water
200
150
100
50
0
Time
Average % As removal of AKF at various flow rates
94%
n = 46
n = 86
% As Removal
92%
Note: For filtered water containing nondetect level of arsenic, a conservative
value of 5 ppb is assumed in the %
removal calculation
n = 75
90%
n = 51
88%
n = 134
n = 40
n = 59
86%
n = 84
84%
82%
1 to 9.9
10 to
19.9
20 to
29.9
30 to
39.9
40 to
49.9
50 to
74.9
75 to
99.9
Flow rate (L/hr)
Insufficient flow
Ideal flow
Performance compromised
100 +
Filter Cost (Gem505)
Gem505
($US)
Container and Lid
$5.55
Basin
$1.03
Piping System
$1.82
Sand & Gravel
$0.04
Iron Nails 5 kg
$4.79
Transportation of
sand & gravel
$0.27
Transportation of
container & piping
$0.41
Labour
$0.74
Documentation
$0.34
Tools
$0.74
Total Per Unit
Cost
$15.73
Note:
No replacement parts needed
except iron nails (nails can
last at least 1.5 years)
Assume exchange rate of
US$1 = 73 Nepali Rupees
Implementation and Scale-up
Implementation – World Bank Project
Funding Source:
• Won a US$115,000 award from the World Bank Development
Marketplace Global Competition 2003
Project Objective:
• To sustainably promote the AKF as an appropriate arsenic mitigation
option throughout Nepal
Project Duration:
• February 2004 to January
2005
Project Partners:
• MIT, ENPHO, RWSSSP
World Bank Project - Key Activities
1. Establish an in-country KAF reference center at
ENPHO to compile all ABF related information
2. Train local entrepreneurs from 10 arsenicaffected districts as “local KAF agents” on KAF
construction, troubleshooting, water testing
3. Conduct workshops to 30 local
governments bodies and 150
villages on health, water
management, treatment
options, and KAF information
World Bank Project - Key Activities
4. Monitor all filters that are in
operation. 2000 filters will be in
operation by Dec 2004.
5. Research & develop better
filter design based on lab
experiment, field observations
and feedbacks from users
6. Evaluate overall project
implementation scheme and
make recommendations to
scale-up project
Is this Project:
Appropriate?
Green?
Sustainable?
Co(m)-passionate?
Design Principles for
Appropriate Technology
(E.F. Schumacher: Small is Beautiful, 1973)




1. Simple design & production
2. Inexpensive
3. Use local materials for local use
4. Rural focus
Yes!
Yes!
Yes!
Yes!
Green?
Design for the Environment
Design for Environmental Protection
Habitat
Design for Resource Recovery
Energy
Species
Soil
Climate
Forest
Air
Materials
Water
Water
 Safe drinking water, but we have not yet had to set up a mechanism to
collect or store spent absorbent media (iron nails)
Sustainable Implementation?
• We select and train entrepreneurs whose businesses are easily
accessible locations
• We provide detailed information to villagers such that they can
make individual informed decision to protect their health
• We strengthen the capacity of
existing local authorities to
support safe water initiatives,
rather than relying on remote
central authority
• We use existing and
functioning distribution networks
and infrastructure; therefore
reducing risk of failure and
negative impacts
Entrepreneurs’ Financial Sustainability?
Financially sustainable:
Margin per unit X unit sales > Fixed cost
Example: About $5.00/unit X 100 units = $500 > Fixed Cost
In our case:
• Fixed cost is minimal because
the entrepreneurs are wellestablished organizations with
their own financial support for
their premises and staff.
• Temporary staff can be hired
to construct filters based on
demand
Co(m)-passionate Technology?
• Filter designed in local environment with local
partners
•Filter designed based on collaborative, iterative,
multi-disciplinary approach inherent in
sustainable development concept
• Filter designed within social and economic
constraints of rural Nepal
• Manufactured by local labor using materials
available in rural Nepal
• Easy operation and maintenance
• Filtered water tastes and looks significantly
better than untreated water (according to many
users) so users like it and are continuing to use it
Future Plans and Challenges
• How to scale-up from 2,000 units (2004) to reach 0.7M in Nepal?
• Increase villagers’ awareness of health and water, targeting the poorest,
the least educated, and in remote western areas.
• Address collection and disposal of spent media
• Continue to subsidize filters for the poorest villagers
• Provide entrepreneurs refresher training & certification
• Continue research on bacteria, viruses, protozoa removal
• Influence government and policy-makers
For Further Information
Susan Murcott,
Lecturer and Principal Investigator
Massachusetts Institute of Technology
murcott@mit.edu
Tommy Ngai,
Lecturer and Research Affiliate
Massachusetts Institute of Technology
ngait@mit.edu
Roshan Shrestha,
Chairperson
Environment & Public Health Organization
rshrestha@mos.com.np
Sophie Walejick
sophiew@stanford.edu
Website:
http://ceemeng.mit.edu/~water
Acknowledgements
In Nepal:
• Environment and Public Health
Organization (ENPHO), Kathmandu
• Rural Water Supply and Sanitation
Support Programme (RWSSSP), Butwal
• Nepal Red Cross Society (NRCS)
• Rural Water Supply and Sanitation
Fund Development Board (RWSSFDB)
• Department of Education (DOE)
• Department of Water Supply &
Sewerage (DWSS)
• Kathmandu University
• Tribhuvan University
Internationally:
• MIT Department of Civil and
Environmental Engineering,
Master of Engineering Program
• MIT IDEAS Competition and
Lemelson Foundation
• The World Bank
• UNICEF
• Stanford University
• University of Calgary, Canada
• University of Texas at Dallas
• Japanese Red Cross Society
(JRCS)
Women who carry the water