Proposal for a Sewage Disposal System for Karachi

SINCE 1980, THE Pakistan NGO Orangi Pilot Project (OPP) has been working with the residents of Orangi township in Karachi to support upgrading, and it has evolved a highly regarded model for the provision of low-cost sanitation which has been replicated in a number of Karachi's informal settlements. The model involves the community-financed and managed installation of in-house latrines, underground sewage lines and neighbourhood-level collector sewers, to be completed by connections to a municipally managed external system. OPP's work has demonstrated the capacity of Karachi's poor citizens, with effective mobilization, to overcome the sanitation problems within their communities – but it has also highlighted the inefficiency and inadequacy of formal municipal responses to Karachi's growing sanitation crisis.

Government schemes to address the problem, assisted by large foreign loans, have failed to improve the situation, and even old, formally planned infrastructure has broken down due to a lack of maintenance. Orangi consultant Arif Hasan argues that this failure is due in large part to a disregard for some important ground realities and existing conditions. Far from complementing and building on systems currently in use, some of the solutions proposed by the municipality would actually involve replacing successful installations.

In this report, OPP offers instead a proposal for a city-wide sewage disposal system that would build on existing systems, make use of and improve the city's natural drainage system and decentralize roles and responsibilities. This proposal, OPP argues, is more compatible with the economic realities of Karachi and would allow for progressive upgrading – rather than committing the population to the repayment of unrealistic loans. Examples from Japan and Switzerland indicate the viability of the less costly alternatives. The proposal is accompanied by a wealth of detailed maps and photographs from different parts of the city, as well as photographs showing examples from Japan of the use of natural drainage systems.