The present civil engineering practice of raising the level of civic roads, providing sewers alongside them and taking sewage outside the city for treatment is environmentally inappropriate and wasteful.  It seriously dislocates the natural drainage, increases the height of the plinths and consequently the cost of housing, and makes sewerage unaffordable by most cities.

Roads & Drainage
The roads should be at ground level with a gradual gradient and designed as the first level with a gradual gradient and designed as the first level storm water drainage channel.  They should run through a common service pipe to avoid opening of roads whenever maintenance is required.

The sewers for disposal of waste should not run along the roads as their function and gradient requirements are different.

Local Sewers
The main sewers designed only for black water (toilet waste), should run alongside the natural water courses or nalas since natural gradients are available there.  The sewers should be designed as local systems and terminated at a number of strategic locations for treatment of the waste within the city.

The size and the cost of such sewers, need for pumping the sewage and consequently energy consumption, will be considerably less than is the case under the present system.  Such local systems can also be built in stages depending upon availability of resources with the civic authority.

Treatment within Cities
The location around the nalas where the black water would be treated should be forested, shallow root zone treatment beds above flood level provided and treated affluent discharged in the nalas.  If in certain seasons there is some small, it can be controlled by spraying certain bacteria now reported to be available in the market, or other biotic methods can be applied.

The nalas, which are mostly used as waste dumps, will, as a consequence, remain clean and can be developed as attractive civic greens with water bodies.  Clean nalas will lead to clean rivers. The areas in the city which cannot be serviced by these sewers can be handled by other local systems like leach pit and biogas.

Absorption of Waste Water
The grey water (water from bath, kitchen, etc.) should be allowed to be absorbed in and along storm water drains, neighbourhood greens, etc., and the water which cannot be thus absorbed, discharged after settlement, directly in the nalas.

Urban waste water, instead of being taken outside the city for treatment, creating waterlogging and unhygienic conditions in rural areas, will thus get largely absorbed in the civic area itself, improving availability of ground water in the city.  Cities have no right to dump their waste in rural area.

The Indore Experience
Such a system, except for the sewage being taken outside the city for conventional treatment, has, through sensitive designing with community involvement, already been implemented in a highly cost effective manner in a slum upgradation project in Indore funded by the Overseas Development Agency of UK.  The project won the World Habitat Award this year.  The approach is thus capable of application in the existing cities.

Need for a Manual
A Civic Environmental Engineering Manual needs to be urgently prepared for propagating such environmentally desirable and highly economical civic infrastructure systems and preventing the onslaught of the present wasteful and destructive civil engineering practices.

The manual can also provide guidelines for organising rag pickers, liberating scavengers as environmental entrepreneurs, greening cities and such other matters.

Development Alternatives & ACUMEN

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