Complex bin routes serving the whole of Leeds are stored...in the heads of the refuse collectors.
No computer script or paper map can compare to the wealth of knowledge belonging to the bin men when it comes to the finer details of the city's bin routes.
The astonishing admission is understood to be a major contributor to the chaos in streets across the city as family after family have been left with no bin collections.
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Men and women refuse workers have been moved around the city during the 10 weeks since major changes were introduced in a bid to save 2.4 million a year.
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And, with them has gone a specialised local knowledge about back streets and quiet areas where bins are stored for many of the city's 330,000 properties.
People have been waiting week after week for their bins to be emptied.
In the first week several thousand bins were left full. At week eight - by which "teething problems" were expected to have settled down - around 1,600 homes were still not having their bins emptied.
The man in charge of the collections admits the situation is "not acceptable" and it seems the multi-muillion pound savings envisaged through the changes are a long way off as 2011 appears on the horizon.
It is now anticipated that in the New Year there could be further problems when management negotiate further with the bin emptiers about their jobs and pay.
The team in charge of the collections has been given until January to sort out the mess.