APPROPRIATE TECHNOLOGY FOR SIMPLIFIED, CONNECTION ORIENTATED - PDF document

APPROPRIATE TECHNOLOGY FOR SIMPLIFIED, CONNECTION ORIENTATED SEWERS KLAUS DIETER NEDER

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INTRODUCTION In Brazil, as in most developing countries, the deficit on ad- In practice this understanding stumbles on the little experience equate basic public infrastructure is still very large, resulting that on the implementation of sanitation systems in low-income ar- a good portion of the population still lacks on services related to eas, which results in the ignorance of the problems that can be water supply, sanitation, drainage and solid waste collection. verified with the conventional approach and the lack of aware- This situation is quite common in the outlying suburbs of cities, ness on the need to seek solutions to correct the problems. where low-income populations are concentrated, as most of the services available in developing countries are located in the The consideration of an alternative technology for anyone not richest parts of the cities. This is especially true with regard to experienced with this kind of situation just seems unnecessary. sanitation, the focus of this work. Expanding sanitation ser- This understanding takes some time to occur, usually in a trial vices to the outskirts of the cities is therefore a major challenge and error process, when the use of conventional technology for developing countries, requiring substantial resources for its results in low performance systems, emphasizing the limitations realization. of this kind of solution. An important consequence of this aspect is that the experience In developing countries, at public utilities, even these findings gained through the implementation of conventional sanitation are not easily achieved, as most of the agents that are involved services in the richer areas of the cities, is, in most cases, mostly with the implementation of sanitation systems are not involved useless when applied in the poor suburbs, where the social, with its operation and maintenance. economic, cultural, as well as the prevailing physical environ- mental conditions are quite different from those observed in Thus, it appears that the challenge for achieving full coverage the finest areas of the cities. This is very important when one with sanitation depends not only on the availability of financial considers that the success of a sanitation system is closely related resources to carry out the works, but also on the promotion of to the environment and the habits of the population of the area the necessary capacity building of the involved agents, so that where it is installed. To be successful throughout its life time, they might understand the various factors involved in the imple- the various factors that may impact its performance must be mentation of sanitation systems in low income areas and the considered from design to its operation. related possible solutions.

LIMITATIONS OF CONVENTIONAL SOLUTIONS Conventional sanitation solutions were developed in urban areas z Infrastructure : Conventional solutions give little attention gifted with most conditions that favor its applicability. The noblest to the lack of proper urbanization in the area where the areas of cities, where income is higher, where people are more systems will be implemented. This fact, together with the used to manage with public services, including sanitation, where usual lack of drainage and solid waste collection services, the urban condition and the availability of other public services is results in an aggressive environment, that usually promotes generally adequate, ended generating the know as conventional the deterioration of the sewers; technologies, which work very well in these conditions, but do not hold up in environments where these conditions are ab- z Technical : Most of conventional sanitation solutions adopt sent. Several factors may be presented to illustrate this situation, a basic misconception on its design, which imposes to the characterizing the type of limitation that conventional solutions users the responsibility to connect to the network. It’s com- feature out of its “original” application environment. mon to see systems that give no special consideration on the topography of the area (regarding the connection) or the z Economic : Conventional sanitation solutions usually result characteristics of the internal installations of the household, in investment and operational costs at levels that people in making it difficult or even impossible to the user to connect low income areas cannot afford, demanding subsidies that to the system; might not be sustainable over the expected lifetime of the z system; Institutional : Conventional solutions give little attention to the lack of adequate organizational structure to properly oper- z Cultural : Conventional sanitation solutions disregard the ate, maintain and commercialize the system, contributing to information deficiency that is verified among the popula- its deterioration, discredit and low economical sustainability. tion to be served, which mostly not used to deal with such a system. This deficiency leads to a low demand for the The disregard of these factors creates systems that do not reach service, resulting in low level of connections, low availabil- the expected number of connections, deteriorate quickly due to ity for payment of tariffs and also misuse, resulting in low the misuse and lack of maintenance, and cannot generate the performance of the system. revenue to make it economically sustainable. 4

THE PERCEPTION OF THE PROBLEM In Brazil, the search for alternative more sustainable sanitation In this sense, the great challenge for the adoption of new solutions was an effort that has emerged throughout the 80s, appropriate technology is to induce the perception and under- with the participation of some actors from the Brazilian sanita- standing of the problems that can occur with the use conven- tion sector, including the academia and civil society, with the tional technology outside of its “natural” environment, the major role of ABES, with the participation of some international wealthier and urbanized neighborhoods of cities. actors (1). The process culminated in the publication, in 1986, of the a new national technical norm, NBR 9649, for the design The fact is that the technicians involved with the implementa- of wastewater collection networks, which incorporated vari- tion of new sanitation systems will only move towards the use ous aspects that resulted from the research performed during of appropriate technology when aware of the limitations of con- this period, including, among others, the use of 100 mm as ventional models and the need to develop solutions for every minimum diameter of pipes and the use tractive tension as the problem that this technology can experience. Therefore, techni- criterion for the hydraulic design of networks. cians need to break with their past experience, recognizing it as an experience limited to particular situations and probably not Although the new norm opened the door for the adoption of applicable to new different situations. new solutions in the sanitation area, including the Condominial model, in practice, a very slow response to the new concepts To work with a scenario of expanding basic sanitation to all the was verified. population, the understanding of these problems is the basis to understand the solutions that might be proposed. The fact is that most agents promoting sanitation in Brazil did not feel the need to change their own concepts in the area of In this regard, capacity building programs for the dissemina- sanitation, understanding that the experience gained so far was tion of appropriate technologies should give special emphasis to sufficient to meet any new situation. The lack of experience in the presentation and discussion of the problems that can occur low income areas created the illusion that conventional solu- with the use of conventional systems, as a prerequisite for the tions were suitable for any kind of situation, a vision that, in presentation of a new technology, which can be present as a some extent, still continues today. solution for those problems.