1.4 Systems Based Approach

Have you ever found yourself in a situation where you realize you should've planned better? One of the most important things to realize about faecal sludge management is that planning is an essential component of sustainable solutions. To ensure the system works requires a complex service chain that depends on interactions among people at every step.

Including the public, private, and civil society, the household level user, the collection and transport companies, operators of treatment plants, and the final end user of treated sludge. In this module I will introduce you to concepts of an integrated approach that this course is based on. Following this module you will be able to explain why an integrated approach to city-wide faecal sludge management requires planning, management, and technology.

Understand how the book Faecal Sludge Management Systems Based Approach for Implementation and Operation fits into that framework. And explain why a sound engineering design approach is required for the design and selection of treatment technologies. In the provision of city wide access to sanitation and sustainable provision of faecal sludge management there are, unfortunately, many examples of failures.

To help understand the scope of the problem and think about what not to replicate here are a few anonymous examples of failures that are based on real life examples. First, a city where a treatment plant was designed based on faecal sludge characteristics that were in published references from other countries. The result was that because local faecal sludge characteristics were not considered, the treatment plant was built twice as large as required.

This represents a waste of financial resources and potential operations problems as the plant will not operate as designed. In another city, the treatment plant was built so far outside of town that truck drivers could not afford to transport sludge that far. This is because land for treatment is difficult to find in dense urban areas.

But the result was that it was never used and trucks continued to dump sludge directly in the urban environment. Both of these examples illustrate the importance of always designing and planning the faecal sludge management solutions based on the local context. In another city there was one designated location for dumping the faecal sludge.

Which was directly onto the beach and in the ocean. So a high core injunction bended. However, the injunction had to be lifted and trucks were allowed back to dump on the beach because with no other alternative trucks just had to find other places to empty their tanks all over the city.

In another city there're over 40 legal collection and transport companies operating, but there's no legal discharge or treatment location. So, obviously, the legal businesses have no other alternative than to illegally dump sludge wherever they can. Both of these examples illustrate the importance of institutional frameworks and the importance of clear roles and responsibilities for faecal sludge management.

Another example from countless cities is a pump breaking at a treatment plant. Resulting in sludge not being pumped out of ponds and tanks greatly reducing hydraulic retention times and in general leading to failure and treatment not being achieved. This illustrates the importance of planning and having a sound operations and maintenance plan in place.

As design engineers and practitioners when working on solutions at any step in the service chain we need to be making intelligent design decisions based on an integrated approach. Engineering design is the formulation of a plan to allow you to build a product or infrastructure with the specified performance goal. For waste water treatment plants that usually means designing treatment to to meet effluent and solid requirements.

Instead, frequently for faecal sludge management decisions have been made on available funding by trying to spend all of it or to be as cheap as possible, or, in contrast, just copying and pasting what worked in entirely different contexts. Which has resulted in projects designed for overly stringent performance goals. That also do not perform as intended and frequently fail.

In an example of an engineering problem solving methodology you have a client who could, for example, be a municipality and you have your specified performance goal that you need to solve for. Then you determine the relevant design variables which include technical aspects, but also social considerations like cultural preferences. Then you further define the problem, develop alternative solutions, and then can take decisions to finally come to your project realization.

We cannot effectively solve problems until we have clearly defined the problem we're trying to solve. In an engineering design approach for selection and design of treatment technologies this means first defining performance goals or treatment objectives Frequently, regulations for the treatment of faecal sludge do not exist or are not enforced. Which also greatly complicates defining performance goals.

One way to do this is to design for resource recovery, which can define performance goals that need to be met while increasing financial flows to offset cost in the service chain. And providing incentive for efficient operation of treatment plants as they're operating to produce products that meet a market demand. Depending on the form of resource recovery defined performance goals are quite different.

For example, pathogen reduction is not as important for use of faecal sludge in combustion. Whereas pathogen reduction is of utmost importance for use as a soil amendment for edible crops. In week 2 we will present you with tools that help select optimal treatment products for your city.

The need for institutional and regulatory frameworks to stimulate resource recovery and other aspects of the enabling environment are part of the sustainable implementation and city wide sanitation planning. However, an engineering design approach is not only about resource recovery. It is first and foremost the protection of public health.

And making intelligent design decisions starting by defining treatment objectives is always essential. For example, if designing for disposal it still needs to be safe disposal. Once you have defined treatment objectives, then you can work backwards considering all design variables to arrive at a treatment technology solution to meet the defined goals.

Overdesigning treatment technologies waste money and resources while underdesigning does not provide adequate protection of human and environmental health. This is why a design approach is so important. Another obvious design variable is what will be going into the treatment facility.

So, you can make it the right size. However, no reliable methods exist yet for the quantification and characterization of faecal sludge on a city wide scale. Or relevant scale for the design of a treatment plant.

So, on week 2, we will discuss ways to approach making reasonable estimates. But what about all these other design variables? They include factors such as existing infrastructure and services, skills and capacities, legal requirements, regulations, norms, social acceptance, operation and maintenance, financial liability.

As engineers and practitioners working in faecal sludge management we need to fill many different roles and realize the importance of why solutions will fail if not part of this larger approach. As we will introduce in week 4 this is where a planning framework helps you to determine relevant design variables. And when in a project cycle to consider them.

A framework will guide practitioners from the initial project planning phase to implementation and ongoing operations and maintenance. In week 4 we will introduce planning and management aspects of an integrated approach that help form the foundation that longterm successful systems are built on. Planning represents the first phase of designing a system, but is necessary to ensure a continuum of success throughout a life of a project.

Management factors such as institutionalization, technical capacity, legal frameworks, enforcement, cost recovery mechanisms and operations and maintenance will also help to ensure long term project success. A systems level approach is necessary to understand how all the steps of a complete system integrate and influence other. To avoid the types of failures presented at the beginning of this module.

An integrated approach at the city level is especially important with the faecal sludge management. As global experience has shown time and time again that onsite and decentralized technologies are prone to failure if not considered as a component within a larger system. In this module we learned why an integrated approach to city wide faecal sludge management requires planning, management and technology.

How the faecal sludge management book fits into that framework. And why a sound engineering design approach is required for the intelligent design and selection of treatment technologies. We will continue to revisit these concepts in the coming weeks.

Thanks for joining! See you next time.