Implementing water filters, but how well do they work?

By Jayne Richards -- Household biosand water filters form a core component of blueEnergy’s water and sanitation program and almost 200 filters have been installed in Bluefields and surrounding communities in the Región Autónoma del Atlántico Sur (RAAS) over the last three years. These filters definitely work in laboratory trials and have been proven to work in various studies abroad. But how effective are these filters in Bluefields, and are blueEnergy’s beneficiaries actually using them properly?

These are some of the questions that blueEnergy’s Vladymir Pao and Jayne Richards are currently trying to answer.

Jayne interviewing a beneficiary in Kahkabila about the use and maintenance of his biosand filter

For the past three months Vladymir and Jayne have been visiting blueEnergy’s biosand water filter beneficiaries to study the social uptake and use of the filters as well as their filtration efficiency. The project forms an important part of the follow up of the Water and Sanitation Team’s work and is funded by Christadelphian Meal a Day. The project includes detailed surveys to determine the use, maintenance and perception of the filters, as well as water quality analysis to determine their technical efficiency.

Vladymir, originally from Bonanza in the north-east of Nicaragua, and a graduate of Ecology from the Bluefields Indian and Caribbean University (BICU), runs the social component of blueEnergy’s Water and Sanitation Program. Jayne, an Environmental Engineer from Australia has been volunteering in the Water and Sanitation Team since November 2011, working on this project as well as blueEnergy’s sanitation program.

Vladymir and incubated water samples from Bluefields

To date, the study has found that the groundwater wells in Bluefields typically have very high levels of faecal coliform contamination. This indicates contamination from latrines or animal faeces and represents a risk to human health if consumed without treatment. The filtered water has typically been found to have zero, or a very low level of contamination, even when there is significant contamination in the source water, thus providing a safe drinking water source for our beneficiaries.

“This study is very useful to blueEnergy," says Vladymir. "It will provide us with extensive baseline data on the distribution and severity of groundwater contamination in Bluefields and two surrounding communities, as well as a greater understanding of what our beneficiaries think of their filters and how they are actually using them. The results of the water quality analysis also allow us to tell our beneficiaries with confidence that their filters are working very effectively and give them more confidence in the technology."

“In Bluefields," Jayne says, "we are finding that the filters are very effective at treating contaminated water but we are also finding some cases of re-contamination after the filtration. This re-contamination is likely due to poor hygiene practices, and highlights the need to continue to promote important hygiene messages during follow up visits after the beneficiary’s initial training session.”

Vladymir and Jayne counting the bacterial colonies in incubated water samples

The project has also enabled blueEnergy to purchase a high quality mobile microbial and physico–chemical water testing kit. This kit will be useful for a range of the Water and Sanitation team’s projects, including testing the water quality from our Baptist wells, biosand water filters as well as water quality testing in remote communities.

Measuring the turbidity of filtered water in Kahkabila

The study will continue until late 2012 and is expected to provide blueEnergy with useful information on the most appropriate implementation model for future biosand filter projects as well as important technical data.

Stay tuned to BlueNews to find out the final results of this study later this year!