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The most important part of the deal to bring in a Dutch company to manage Harare City Council’s Pomona dump site is that it will be managed, rather than just having the garbage piling up and bursting into flames every now and then and spreading toxic fumes across northern Harare.

The actual deal sees Georgenix BV using the garbage to run an electricity generation plant, which will be able to sell electricity to Zesa and help the company recoup its €303,9 million investment in the design-build-operate-transfer deal signed off this week.

While the deal is between the city council and the company, it was backed by the Government, who usually need to approve such schemes as well as offer guarantees, and have been pressing the city council for some years to figure out a way of collection and disposing of the garbage from the largest metropolitan area in a more efficient and safer way than we have been doing.

Such plants that convert garbage to energy are becoming increasingly common around the world, with the processes being an efficient way of minimising the amount of residue that has to be disposed of in land fill as well as generating energy.

The most common plants burn the garbage in a special incinerator that fuels a thermal station, using the steam to run a turbine and generator. This can use all the garbage except for metal and glass. The other technique if garbage is better sorted is to use the pure organic rubbish in a methane generator, and then use the methane to run a gas generation plant. 

Some even use both, the organic rubbish making gas and the inorganic combustible rubbish being burned. 

But for this to work properly households and businesses have to sort their rubbish, usually into a range of different coloured garbage bags so when the trucks drive up to the garbage dump the organic, paper, plastic, metal, light glass and brown glass garbage is already sorted and tagged for different uses.

It is clear that getting Harare households to do this is, at present, nigh impossible even though such a system can come close to paying for itself without refuse removal fees on the rates bill. 

It also allows for maximum recycling of garbage and allows the most efficient conversions of garbage to energy. So it is a pity that probably have to wait for such a complex system even though a few businesses are trying it out.

But even the standard incinerator steam plant converts vast amounts of garbage into ash and cinders that occupy far less space than the original rubbish and are an inert product that can be converted to land fill without any danger of spontaneous combustion or other danger. And it can be upgraded later on when all households are willing to move to the full sorting system.

Of course, one requirement of such plants is that the garbage is collected, and Harare City Council are hardly doing what they should be doing right now to collect it. 

We pay for this, but we keep getting told the trucks are broken down or given some other excuse. 

So we tend to see garbage dumped on open spaces near houses, in stream beds and the like, and this is hardly helping keeping our city clean.

All large cities and metropolitan areas generate a lot of rubbish and regrettably the average from each household rises as countries get richer and people throw more away. Harare has been using landfill for decades, but there are limited suitable areas now for this to be a suitable system, especially with the modern range of rubbish.

In earlier years when plastics were rare and most rubbish was organic, paper, metal and glass landfills did not need much space and the garbage quickly compacted and was rendered safe, so all that had to be done was to compress it and then place regular layers of gravel and earth on top of each layer. Some rather good industrial sites were built up this way.

The quarries used to get the clay to make bricks or the stone to make concrete or road paving have for the last 40 years been the most common assigned dump sites, hence the present operation in Pomona, the site of a very large old quarry. 

But there was going to be a problem reasonably soon when all the holes were filled and finding a new site was obviously going to be a problem.

Better management and processing of the garbage will extend the life of the Pomona dump for a good many years and perhaps late this century there will even be a decent recreational area for the nearby Hatcliff suburbs.

Landfill is not suitable as a base for housing, but can be used for industrial land and can, with a decent layer of soil, be a good area for sport and the like. 

As Zimbabwe moves up the ladder of prosperity and as Harare, one day and probably under new management, does start reflecting its status as a major African city, we will need these recreational areas, especially as the present council has been so determined to convert what we did have into dubious housing areas.

And while that new plant produces a by-product of electricity, perhaps this new lease of life for Pomona will give time for the city council to upgrade its collection service, will allow the conservationists time to persuade Harare residents to sort their garbage before collection, and will allow the garbage to go to Pomona instead of littering the streets or being dumped in every stream bed in the city.