Hello, and welcome to the MOOC module Shit Flow Diagrams: A tool to illustrate and communicate sanitation service delivery. My name is Lars, I'm an environmental engineer and I'm working in the department of sanitation, water and solid waste flow development. <i>Shit flow diagrams are often referred to as SFDs, <i>and in 2015 a team of organizations came together <i>to develop a consistent approach for the production of SDFs, <i>and the description of sanitation service delivery. <i>I hope you are excited to learn about the SFD, excreta management, <i>and the overall link to sanitation systems <i>and fecal sludge management. At the end of this module, you'll be able to describe what an SFD could be used for, explain the different pathways excreta can take in the environment, and provide examples of safely managed and unsafely managed excreta. To start, let's answer the question of what the SFD can be used for. The SFD is an assessment of sanitation service delivery, which is helpful for understanding the current situation. The SFD is a communication tool, which presents complex information in a simple illustration. And the SFD is an advocacy tool. It can be used to demonstrate the need for improved sanitation service delivery. Now, let's discuss what the SFD can convey. The SFD conveys percentages of excreta transported through sewers or emptied from containment, but it's not a detailed planning tool. It also shows how much is delivered to treatment, but it's not a quantification tool with accurate volumes. Lastly, it shows percentages of excreta treated or not treated, but doesn't assess treatment performance. <i>Let me just briefly introduce you to the research behind the SFD. <i>Discussions about SFDs are only possible <i>if results are based on a consistent approach. <i>On this slide, you can see an example. <i>This SFD is based on the methodology and tools <i>which are available on the website. <i>Green and red arrows illustrate safely and unsafely managed excreta <i>along the sanitation service chain. <i>The SFD method provides guidance to derive these percentages, <i>but also defines terminology. <i>During the following minutes, I'll guide you through a city <i>to explain this terminology in more detail. <i>Here you can see an example city. <i>Excreta is managed with off-site and on-site sanitation. <i>The SFD starts out by separating those two sanitation options. <i>This pictures shows a typical wastewater treatment plant. <i>Ideally, wastewater is delivered to treatment. <i>If not delivered, or not treated, <i>we refer to it as "excreta unsafely managed," <i>as shown here in red. <i>But if the wastewater is treated, <i>then we refer to it as "excreta safely managed," <i>as shown here in green. <i>Here you can see a pit latrine, which is an on-site sanitation technology <i>used by the majority of the population in low-income countries. <i>Fecal sludge accumulates in these technologies, <i>and once the containment fills up, the sludge needs to be removed. <i>In this example, a manual emptying-service provider <i>collects fecal sludge in barrels, <i>which are then transferred to a pickup truck. <i>On the SFD, this is described as "fecal sludge emptied." <i>The terms "fecal sludge contained" and "fecal sludge not contained" <i>will be explained in a later scene. <i>Ideally, fecal sludge is then delivered to treatment, <i>the next step of the sanitation service chain. <i>If delivered, the arrow on the SFD is green. <i>In this example, you can see a septic tank, <i>another common on-site sanitation technology, <i>which is connected to flush or pour-flush toilets. <i>If the groundwater and soil conditions allow, <i>the effluent infiltrates through a soak pit <i>into the ground for natural treatment. <i>Solids settle at the bottom of the tank, <i>and fecal sludge has to be removed on a regular basis. <i>If not removed, tanks can overflow, <i>and this can result in groundwater pollution. <i>Instead of using barrels, septic tanks are usually emptied by vacuum trucks. <i>If delivered to treatment, the arrow on the SFD is green. <i>Here you can see a typical fecal sludge treatment plant. <i>Liquids and solids are separated in settling tanks. <i>The solids are then transferred to drying beds, <i>while the liquid part is often treated in ponds. <i>If treatment is effective, fecal sludge is described as "treated" on the SFD, <i>and therefore safely managed. The next scenes will provide you with more examples of unsafely managed excreta, which is a common situation in many places. <i>Where sanitation facilities don't exist, <i>open defecation is practiced, <i>which directly contaminates the environment, <i>and is considered unsafely managed. <i>The next examples show situations where fecal sludge is emptied, <i>but then not delivered to treatment, as described on the SFD. <i>Where sanitation facilities exist, <i>but vacuum trucks cannot access the facility, <i>dumping of fecal sludge directly into the environment is common. <i>Fecal sludge is directly flushed out into nearby drains <i>by removing bricks from the containment, or by installing pumps. <i>Informal emptying practices also often lead <i>to dumping of fecal sludge into the nearby environment. <i>On the SFD, both scenarios are referred to <i>as "fecal sludge emptied, but then not delivered to treatment," <i>and therefore unsafely managed. Let us now look in more detail into the definition of "fecal sludge contained" and "not contained." <i>To do this, we need to look at the water table and soil conditions. <i>The animation provides you with an example <i>of a septic tank and a pit latrine that infiltrate into the ground. <i>In this first scenario, the water table is low, <i>and therefore the risk of groundwater pollution. <i>The result is fecal sludge contained, as you can see on the SFD as green. <i>Another scenario is that the water table is high, <i>and in this case, infiltrate from the septic tank and pit latrine <i>drains into the groundwater. <i>This situation causes a significant risk of groundwater pollution. <i>The result is "fecal sludge not contained," <i>which you can see on the SFD as red. <i>In places where there's enough space, <i>a common practice is to cover a full pit with soil, <i>and then build a new one. <i>If groundwater pollution is not an issue because of good soil conditions, <i>and low water table, this practice could be considered as safely managed. <i>While it can provide a solution in rural settings, <i>this should not be promoted in urban settings. You have now learned about scenarios where fecal sludge is not safely managed due to a number of reasons. But I hope you're not surprised if I tell you that even fecal sludge emptied and collected by vacuum trucks often is not delivered to treatment. <i>There are many possible reasons for this. <i>Firstly, treatment plants for fecal sludge <i>may simply not yet exist. <i>Fecal sludge is dumped into the environment, <i>and on the SFD considered as "not delivered to treatment," <i>and therefore unsafely managed. <i>Another common scenario is that treatment may exist, <i>but is located far outside of the city. <i>In overcrowded cities where traffic jams are the reality, <i>fecal sludge gets dumped into the environment, <i>which again is referred to as "unsafely managed" on the SFDs. <i>But even where treatment exists and is reachable, <i>high fees for discharge may discourage service providers <i>to actually deliver sludge to treatment. <i>The last situation shows trucks that deliver fecal sludge <i>to a wastewater treatment plant. <i>This typically results in failure of treatment processes. <i>The SFD illustrates this as "fecal sludge or wastewater not treated," <i>and therefore unsafely managed. <i>Let's zoom out of our city again. <i>You have now learned about the SFD terminology, <i>and what unsafely and safely managed excreta means. I hope you enjoyed this animation. So now, before we finish this module, I would like to show you one more example of a real SFD. <i>Here you can see the SFD for Dar es Salaam in Tanzania. <i>On the left-hand side, you can see <i>that 9% of the population uses off-site sanitation. <i>90% of the population use on-site sanitation, <i>and 1% practices open defecation. <i>In total, we found that 43% of excreta are safely managed, <i>and 57% are unsafely managed. <i>Of the 57% that is unsafely managed, <i>the majority results from fecal sludge that is not contained and not emptied. <i>This is the scenario we have shown you in the animation, <i>where the water table is high <i>and excreta infiltrates into the groundwater. <i>Additionally, more than half of the emptied fecal sludge <i>is actually not delivered to treatment, <i>and directly dumped into the environment. <i>This contributes another 18% to unsafely managed excreta. <i>Of the 43% safely managed excreta, <i>a major contribution is fecal sludge contained and not emptied. <i>SFDs represent the current situation. <i>At the time this one was made, <i>many pit latrines were built quite recently, <i>and simply not yet full. <i>Once these pit latrines need to get emptied, <i>treatment infrastructure needs to be available <i>so that emptying service providers <i>have an appropriate location for discharge. <i>If not, the percentage of unsafely managed excreta <i>would increase significantly. The SFD promotion initiative has developed a methodology, tools, and templates for worldwide production of SFDs, using the terminology presented here. To learn more about SFDs, please visit the project website, where all those materials can be downloaded. Is there an SFD for your city? If not, maybe you can start producing one, and use it to raise awareness about the gaps in sanitation service delivery. Thanks for listening to me today. We really hope you enjoyed this module.
