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IT is rare for a year to pass without some community in Zimbabwe being threatened with floods and being forced to abandon their homes, with the defence forces and the police often having to take a lead in the rescue efforts.

Some floods are almost annual events. The north east of Zimbabwe has seen more than its fair share of such floods; the problem there is not so much an assessment of risk, since the floods are frequent.

Rather it is trying to persuade people to live further from their fields and pastures so that their homes are on land that is never or very rarely flooded. Some people still accept higher risk in return for convenience, just as some people drive unsafe cars rather than walk.

And then there are the occasional floods, sometimes heralded by the arrival every one or two decades of a cyclone, or the strong remains of a cyclone, riding in from the Indian Ocean. But while these produce flooding over wide areas, every Zimbabwean has seen local flash floods, where heavy rains temporarily turn little streams or even dry stream beds into raging torrents of powerful and destructive fast moving water.

But as Local Government, Public Works and National Housing Permanent Secretary Engineer George Mlilo has noted, flooding is possibly the most manageable of natural disasters.

Some management is obvious. It is easy to find the high water mark of almost every river at every point along its course. Signs on the ground and memories in local communities will quickly produce a line on the ground that a river has, at some stage within the last few decades, reached.

It does not need a genius to recognise that houses in that area should be built higher than the worst high water mark, along with as much other critical infrastructure as possible.

In urban areas, where roads and roofs ensure that a higher proportion of rain is turned into runoff almost instantly, recent changes in the maximum height of urban water courses might mean that drainage has to be improved and parts of river beds widened or deepened to clear that extra runoff more quickly.

Bridges are supposed to be designed to cope with floods. This was obvious in the old days with low level bridges, which were regularly submerged for a few days at a time during the rains, but newer bridges can be susceptible to flood damage and designers need to keep that in mind; they are the most obvious structures to be built in flood prone areas.

So smart management in where we build things can minimise the risk of flood damage.

Modern meteorological science, with access to satellite imagery, can give good warning of most likely floods. Cyclones and serious tropical storms can be tracked and Zimbabwean communities given adequate warning, at least a day or two.

Fortunately, we are too far from the sea for the near instant tsunami floods. What is needed for these rarer special floods is a system where everyone likely to be affected can receive the warning and take simple precautions and these, if we have introduced better management of our flood plains, might be no more than telling people not to go into their lower lying fields and pastures and not to use certain portions of nearby roads or bridges.

If houses have been built in safe locations, then just telling people to stay at home for the next three days might be all that is necessary.

There is a lot of technology now available, including excellent satellite imagery of the whole surface of the country at different seasons and over the past 20 years or so.

This is helpful, but needs to be applied with common sense, a willingness to ask local communities about the past to fix high water lines precisely, and a willingness by everyone to take sensible precautions, both in siting homes and other structures and in how to cope when there is flooding in the area.