Los Arcos of Danli community slow sand filter tour

As told by Michael Reed:

In February we visited the community slow sand filter in Los Arcos – a small suburb outside of Danli, Honduras.

The Los Arcos community has had a water system (i.e. piped in water to their houses) since 2005, and in 2009 PWW helped build a slow sand filter.  The filter serves 240 homes and was designed for a flowrate of 5 liters/second (80 gal/min).

I met with the water system/filter plumber and he provided a tour.  By all accounts the slow sand filter is working very well, with full community support and no technical problems.  Very little maintenance is required for correct operation of the filter.  Water is available to half of the community every other day (section A on Monday, section B on Tuesday, section A on Wednesday, etc.)  The system is continuously being chlorinated.  The Junta de Agua has set a sustainable tariff level (40 Lmp/month), and has a sizeable reserve in the bank ready for an emergency.

Six water samples were taken to analyze the effectiveness of the filter.  Two samples were taken from the source, two from the filter outlet, and two from a water tap at a house.  The results were very encouraging – the source showed high levels of E. coli contamination (average > 30 coliforms/100 mL).  The four other samples, representing the filter effluent and household water, showed 0 E. coli.  The filter is clearly working well and the chlorine disinfection is an added layer of protection.


PWW Executive Director Carolyn Meub, and PWW Board Member Barbara Carris, visited the Los Arcos filter in 2014.