Recommendations to USAID/Haiti for LF-Series Tablet Feeder Chlorinators

Daniele Lantagne, PE

CDC

Rochelle Rainey, PhD

USAID

Background

• Community-based chlorination– Common in Central America– Tablet feeders (LF-500, LF-1500)– Hypochlorinators

• One Published Paper (Henderson et al, 2005)

– Tablet feeders (like the LF-500) are more effective than hypochlorinators

The LF-series in Haiti

• International Action– Washington-based NGO– Funded to provide 100 LF-series to Haiti– Working with POCHEP, CAMEP, and SNEP– Technical Assistance from IRWA

• Daniele received email asking for NGOs to receive LF-series– Connected Jolivert, Bethel Mission– Attended training for NGOs on May 8, 2006

How it works

• Flow in (from left) and diverted• 2 valves manipulated to control flow

– Treatment pipe and Main pipe

• LF-500 doses water in treatment pipe to ~5 mg/L chlorine• Technician tests mixed finished water

– If test shows not 2.0 mg/L chlorine, technician adjusts valves – Iterates until correct residual

• Water flows to tank or distribution system

Main Pipe

Treatment Pipe

Chlorine Tablets

Responsiveness to Water Quality

• All dependent on testing of effluent water

• If low chlorine demand adjust valves so more flow through main pipe– Clear water

• If higher chlorine demand adjust valves so more flow through LF-series treatment pipe– Dirty water– Contaminated water (dead horse upstream)

Concerns for LF-500

• Continuous supply of tablets to projects• Use of LF-series in intermittent situations

– Shock of higher chlorine dose with first flush

• Responsiveness of LF-series to influent water quality– Dependent on Technician testing water

These concerns are more important in smaller systems with discontinuous flow (less margin for error), and less

important in continuous flow, larger systems where shock loading or underdosing will even out in distribution

or tank.

Existing Sources in Rural Haiti

USAID Rural Water Focus

Benefits of LF-500

• Provision of appropriately dosed chlorinated water to communities

• Simple system

• Low-cost

• Need for only one point of intervention per community

Important Educational Messages

• Adequate and sufficient testing of effluent water

• LF-500 best in (semi)continuous flow situations

• Training of Operator and Community Organization– Tablet and DPD testing supply chain– Maintenance

• Decision tree for use– Small water supply systems use hypochlorite?– Medium supplies use tablet feeder?– Larger supplies use diluted calcium hypochlorite?

Recommendations to USAID

– Connect Int’l Action with JICA and IADB rural infrastructure projects

– Work to provide information to Int’l Action to:• Provide technical information to partners • Select appropriate locations for interventions

– Under sustainable circumstances in (semi)continuous water supplies LF-500 can be an appropriate intervention in Haiti