Hi Jenny,

Thanks for the post, your question on the applicability table in the sanitation and health guidelines is really interesting.

You are quite right, the idea of the table is to highlight where the systems are best suited/most applicable, it is not suggesting a hierarchy. Making the decision on what system to use where is entirely dependent on the context. This issue is highlighted in the introduction to chapter 3 of the guidelines and was succinctly highlighted in Kate and Sophie's WHO webinar quiz…see questions 6 and 7.

So I would expand on two important parts of this:
1. Design the solution in terms of a system (the toilet and after the toilet) i.e. the whole sanitation chain from containment through to treatment and end use/disposal. So if you recommend a toilet connected to a septic tank with a soak pit, you need to design the whole system; thinking about the method for emptying the faecal sludge when the tank fills up, how it will be transported to treatment, how it will be treated, and what will be done with the treated product? And
2. Think about who will manage all the different parts? Not just cleaning the toilet and emptying the septic tank but the transport, treatment and end use/disposal as well…including human resources, capital maintenance, O&M, financing etc. For instance, there may be a treatment plant already that the faecal sludge can be taken to, but is it functioning and if so, will it accept faecal sludge?

I don’t know of a complete and authoritative guide or handbook to refer you to, but alongside the new guidelines there are useful tools out there which you can find. For example, the FSM toolbox and PATH’s sanitation technology filtering tool; and there are a bunch of references in chapter 3 that you might find useful (take a look at Tilley et al, 2014; Strande, 2014; and Tayler, 2018).

Good luck!

Andy
(Member of the guidelines development group)

Hi everyone,

From my first look in the guidelines I see there is a table showing the applicability of the different sanitation methods for different cases. However is there any guidance on the order of preference? Some kind of hierarchy to help make the design decision. To explain my context, I'm working in Rwanda as a civil engineer and the company I'm with has a whole variety of different kinds of projects. From refurbishing a school that is using pit latrines, up to a university campus that will have it's own wastewater treatment plant. And it's the projects in between that I think it is hard to make the decision for the appropriate level of waste treatment. Septic tanks going to a soakaway are the most common solution, but when the project has the funding to do a 'better' solution, it would be good to have the backing to show why something more than a septic tank should be used to - and if this is even the case!

Any advice would be great!

Jenny