IN-SITU FILTRATION WELLS IN RURAL HAITI

Wells are common in many developed communities in Haiti, but are uncommon in the rural mountainous areas of Haiti where natural springs are abundant. Rural Haitians typically send family members, usually women and children, to fetch water at springs 2-3 times daily using a combination of buckets and plastic containers. Bacterial contamination is common in natural springs in Haiti due to surface contamination, vulnerable karst aquifers, and inadequate sanitation. A common practice has been to install a concrete structure to protect the area where the spring emerges. This is often combined with in-home treatment such as biosand filters or choline tablets. Water testing indicates that water protection and treatment methods in remote mountain areas do not always succeed at providing consistent safe water sources for many rural Haitians.

In June 2013 an alternative approach, referred to as in-situ filtration (ISF) wells, was tested on two pilot wells in the commune of Verrettes. An ISF well combines hand-construction techniques compatible with remote locations, simple and inexpensive hardware and maintenance, and the convenience and protection provided by a drilled well. ISF wells provide enhanced filtration with a larger sand pack than traditional wells. Two types of ISF wells were constructed in 2013. One well was created by converting a 6 meter-deep hand-dug well (Bachemir’s Well); and the other was a newly excavated 3 meter-deep hand dug well adjacent to a natural spring (Jaden Nivo). Both wells were fitted with perforated PVC pipe and backfilled with sand so that all water entering the surface-mounted pitcher pump had to pass through approximately 0.6 meters of sand.

In 2011, Jaden Nivo spring had 56.9 e. coli /100 ml MPN; and Bachemir’s well had greater than 2420 e. coli/100 ml MPN. Monitoring immediately after ISF well completion indicated increased e. coli for Jaden Nivo (2420 e. Coli /100ml MPN); and slightly decreased e. coli for Bachmir’s well (1553 e. coli/100 ml MPN). Within 90 days both well installations had e. coli of 1 e. coli /100 ml MPN or less. The spring adjacent to Jaden Nivo continued to have elevated e. coli in the 10’s of e. coli/100 ml MPN. Two additional wells were installed in 2014. The cost of each well conversion was approximately $400-500 U.S., roughly one-tenth the cost of a traditional well.