​Designing on-site sewage treatment for people and not their products

By Simon Ross, IWCAN

In an interview, Jason Jaskowiak, Wastewater Chief of Aqua Consulting in American Samoa described the importance of local people learning about on-site systems and how this can be used to improve groundwater quality and public health in the Pacific. He is candid about the need to consider the resources and cultural preferences of local people living in non-sewered areas, particularly when their participation and willingness to pay for improved on-site treatment processes are critical to protecting local groundwater resources.

This article presents some of the contextual challenges faced in American Samoa with respect to implementing improved septic system designs. Jason challenges water practitioners who are interested in working in contexts like this to forget what they have been taught and innovate based on local knowledge.

Local environmental considerations

Groundwater contamination from cesspools has a significant impact on water management in American Samoa and needs to be urgently addressed. Loose volcanic soils contribute to non-revenue water (NRW) losses of 60% or more and their high permeability means that nitrogen and E. coli often contaminate groundwater supplies used for drinking water. This results in regular ‘boil water notices’ affecting the majority of the population.

Ecological pressures exist not only from human waste but also from piggeries. Pig raising is a widespread, culturally-important, domestic activity. Previously, a compliance program for domestic piggery waste, which is also traditionally stored in cesspools, was required to address widespread leptospirosis outbreaks. Contaminated water that accesses the marine environment can also have major economic impacts as the island’s industry is based on tourism related to pristine coral reefs and fisheries.

Source — USGS: Using thermal imaging to determine the extent groundwater flows to the reef

Jason Jaskowiak describes the approach taken on the island:

“We have changed the way we install the systems and deliberately created a barrier of compacted material to slow the percolation rate to inhibit the growth of biofilms so that water is treated more effectively.”

However, even though these cost of on-site systems is less than centralised options, subsidies to build these systems are only currently considered where old houses are located close to important water resources. Currently, demand is created for on-site systems by blocking access to loans when people build or renovate houses until an improved septic system is installed. These systems are more expensive than traditional approaches (cesspools) and conflict may arise when costly and labour-intensive maintenance is required to address improper disposal of grease, chemicals or sanitary products, which negatively affect the performance of these on-site systems.

Typical cesspool in use in American Samoa. Source: College of Tropical Agriculture and Human Resources, Hawaii.

Local cultural preferences

Jason discusses the challenges of communicating the importance of the new systems to residents and why they are required in response to long-established practices of residents using cesspools to managing sewage, which does not provide any containment or treatment of waste before entering groundwater tables.

Jason Jaskowiak describes some of the complex challenges with getting people to change their habits when they install new systems:

“There are plenty of septic options that we could use in many areas that would work great in other places, but they’re not passive systems. When a pump, electricity, or ongoing maintenance is required, nobody is willing to pay for these things because of just the way the culture is. It is difficult to engage people when money is coming from their pocket. Communicating how costly it will be if the system is not maintained properly is an uphill battle.”

On-site sanitation service design that engages with these preferences

In the interview, Jason emphasises the importance of social as well as technical innovation:

“To come out and work in this area, you have to be able to look at the resources you have, look at the problem you face that you can’t change, and meet those. You have to spend time understanding the culture and what works, what the challenges are, rather than just applying what you already know.” Jason Jaskowiak, Wastewater Chief, American Samoa Power Authority

There is value for both water professionals and people in American Samoa in sharing their experience of innovating with the design, implementation, adaptation of on-site sanitation, with each other. There is also benefits in other water practitioners in the region from engaging with this cultural knowledge and perhaps rethinking their own approaches. These learning processes are essential to inform the ongoing design of non-sewered sanitation services across the Asia-Pacific that are relevant, effective, and sustainable, which is vital to reducing the 80% of wastewater in the region that is discharged to the environment without treatment.

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