Implementing Water, Sanitation & Hygiene (WASH) Approaches During Emergencies

Guest Lecture at MIT D-Lab Class: Disseminating WASH Innovations

Tom Mahin April 12, 2011

From CAWST

Emergencies - Natural Disasters, Conflicts & Outbreaks

Adapted from Lantagne & Clasen 2009

Examples of Emergencies and Potential Waterborne Pathogen Outbreaks

• Seasonal Flooding - significant potential for pathogen

contamination of shallow wells and springs and flooding of latrines

• Earthquakes – damage to drinking water and wastewater-sanitation infrastructure

• Conflicts - potential for inadequate water, sanitation & hygiene in refugee/internally displaced persons camps

• Hurricanes/typhoons/cyclones/tsunami – flooding (contamination of water sources) and damage to water and sanitation infrastructure

Displacement of Large Numbers of People Increases the Likelihood of Waterborne Disease Outbreaks

Cholera

• Cholera is caused by V. cholerae bacteria.

• There have been numerous outbreaks in Sub-Saharan Africa in Asia and now in Haiti.

• Coastal countries are at particular risk because the bacteria can survive very well in coastal areas particularly in rivers that empty to the ocean.

A Number of Waterborne Pathogens Cause Increased Diarrhea Cases During Flooding

From Harris et al. 2008

From Colindres et al. 2007

Community Water Sources Before and After Flooding Haiti (Gonaives) 2004

• Between July 14 and 17, 1994 approximately 800,000 ethnic Hutus fled Rwanda and sought refuge in neighboring Zaire (now DRC). Many refugees entered through the town of Goma, at the northern end of Lake Kivu. • A massive cholera outbreak spread quickly and very high death rates resulted. The hard volcanic soil prevented the building of traditional latrines and Lake Kivu which was used for bathing and drinking quickly became contaminated with cholera (Goma Epidemiology Group,1995).

Cholera Outbreak - 1994

Examples of Different Chlorination Approaches Used During Emergencies

• Water trucking with chlorination

• Point of Use – Household Chlorination (e.g. distribution of NaDCC tablets, promotion of dilute sodium hypochlorite)

• Chlorination of community/municipal water systems at either the reservoir tank or a water collection point (well, tapstand on piped system, small spring, etc.

Chlorination and Cholera

• Chlorinating and maintaining a chlorine residual in water used for drinking is a proven way of significantly reducing cholera rates.

• However a number of challenges exist particularly for rural areas.

Chlorination Challenges – Household Chlorination

• Providing large amounts of NaDCC (chlorine) tablets as is required is logistically complicated and raises significant long-term sustainability issues.

• Use of NaDCC tablets of significantly different dosages in Haiti has made training in proper usage more difficult.

• Household bleach is more commonly available but is more difficult to properly dose (e.g. varying % chlorine & dosing of drops per gallon). In addition, bleach can include perfumes and is perceived by some as meant for laundry not drinking water.

One NaDCC Manufacturers Varying Doses for Household Use

Medentech

Chlorination Challenges - Gravity Flow Systems

• Proper mixing of “batch” chlorine in reservoir tanks is difficult because such tanks are usually designed for settling/storage not mixing.

• Regular monitoring of chlorine residuals is an important part of community systems but is under performed in many rural areas.

• Solution – need both improved (more consistent) chlorine dosing at tank and more frequent chlorine residual monitoring

Potential New Approaches to Chlorination of Community Systems during Emergencies

Point of Water Collection Chlorine Dispenser

From: Trickle Down: Chlorine Dispensers and Household Water Treatment by Kremer et al. 2009

Chlorine Dispenser - Haiti

Chlorine Dispenser

From Fitzpatrick 2008

Communicating Proper Dose

From Kremer et al.

Challenges for Making Chlorination at Water Collection Points (e.g. dispensers) Sustainable

• Common use of different size containers mean different doses of chlorine. Solution may be to have 2 clearly marked chlorination points, one for “1 gallon” jugs & one for “5 gallon” containers.

• Having a system that results in regular preparation of replacement chlorine solution.

• Advantages/disadvantages of using calcium hypochlorite (HTH) vs. NaDCC tablets for chlorine (ease of use vs. availability/cost).

Tablet Chlorination System for Tanks

• Water from pipe - part is diverted and part is chlorinated • 2 valves manipulated to control flow • Technician regularly tests mixed finished water

Technician adjusts valves based on results & iterates until correct residual

• Water then flows to tank, helps even out chlorine levels Adapted from Langtane and Rainey - Recommendations to USAID/Haiti for LF-Series Tablet Feeder Chlorinators

Tablet Chlorinator - Nicaragua

From Fitzpatrick 2008

Sanitation and Emergencies

MacDonald and Callow 2009

Some Sanitation Challenges

• Need to pump out or “desludge” latrines that get heavy use or that pose threat to groundwater - need “desludging” equipment & sludge disposal location.

• Need better solutions for odors in high density spontaneous settlement areas with limited space for setbacks for latrines.

• In areas prone to flooding, latrines must be elevated “raised.”

Photo by Jerry Carreon/Oxfam

Examples of Raised Latrines

Hygiene and Emergencies

• Hygiene education that results in increased handwashing, sanitation and use of treated water is a powerful means to reduce diarrheal disease outbreaks during emergencies.

Risk factors for Cholera - Zambia

Sasaki et al (2008) Spatial Analysis of Risk Factor of Cholera Outbreak for 2003–2004 in a Peri-urban Area of Lusaka, Zambia Am. J. Trop. Med. Hyg., 79(3), pp. 414–421

Haiti - Hygiene Communication Challenges

• Effectively establishing as consistent message/understanding that cholera can come back as strong during/after the rainy season(s).

• Proper dosing of NaDCC tablets (because of the different products (manufacturers/dosages) being used.

• Building awareness that the solid waste situation in urban areas can contribute to drainage related flooding increasing cholera risk (due to drains clogged with trash).

Case Study: Safe Water and 2 Emergencies Haiti 2010 - 2011

Emergency 1 – 2010 Earthquake

One Approach Used to Provide Safe Water Post-Earthquake

• A mix of bladder tanks and “Tuff” tanks were installed along with piping, tapstands, , etc. at spontaneous settlements “camps” and at orphanages.

• Oxfam contracted with company to use project dedicated water tanker trucks to haul water from a deep well to a number of locations.

One Approach Used to Provide Safe Water Post-Earthquake (cont.)

• Oxfam made up fixed amounts of chlorine in bottles and provided them on a daily-every other day basis to camp water committee members trained to add to empty tanks prior to water being pumped (helps in mixing) from tanker trucks.

• Chlorine residual at tanks was checked regularly (usually daily) by Oxfam.

Digital Chlorine Analyzers

• Digital colorimeters are the most accurate way to measure chlorine residual in the field but are more expensive than “pool testers”.

• Chlorine levels were regularly tested at spontaneous settlements where Oxfam was providing chlorinated water

Emergency 2 – Cholera Response

Cholera Response – Safe Water

• Assisting communities in the repair of broken or partly functioning gravity flow (spring) systems

• Hand drilling of new wells

Cholera Response (cont.)

• Distribution of NADCC tablets with local partners

• Chlorine residual testing at households

•Provided digital chlorine meters & user training to Cholera Treatment Center (CTC) , hospital & Haitian NGO

Cholera Response (cont.)

Cholera Response – Safe Water (continued)

• In new location/office in Nippes area, some of the newer chlorination approaches discussed in this presentation will likely be used (April – Sept. 2011).

• An assessment conducted in March indicated that in general chlorination of community systems was not being currently practiced which represents a significant risk during the upcoming rainy season(s).

Thanks for listening!

Any questions?