London seems to be returning to the middle ages, with a growing dearth of public toilets prompting an epidemic of peeing that is raising, literally, a stink.

The British Cleaning Council claims London's street cleaners scrub away around a million litres of urine each year, as people caught short spend a penny al fresco, usually in doorways, backstreets or behind hedges (known in the sanitation trade as 'wet spots'), mostly after the pubs close.

But it's not just late-night drinkers. All citizens bemoan the lack of toilets when nature calls.

London has lost up to 40 per cent of its public conveniences over the past five years, according to a report for the London Assembly, the capital's governing body, with 701 toilets watered down to 419.

That's one toilet for every 18,000 residents. With 28 million visitors a year that's one per 67,000.

It's not just street provision. Only 88 of the 225 London Underground stations have public toilets while the 6.3 million daily bus passengers have access to toilets at just 13 stands.

There are even reports that the uric acid passed by those awaiting night buses in Trafalgar Square is eroding the walls of the National Gallery. Not quite the picture tourism chiefs intended.

Why so few toilets? Blame cost-cutting by local councils, all keen to avoid the high costs of bringing the decrepit, cramped, ill-equipped and often underground Victorian toilets into line with modern disability discrimination laws. Although there's no statutory duty to provide toilets, rules ban councils from charging to use urinals. Toilets, in short, are a huge drain on the public purse.

The report, An Urgent Need, fears the lack of lavatories will hurt London's reputation come the 2012 Olympic Games with public peeing becoming acceptable, the assembly's health and public services committee says.

The official 'Blue Badge' tourist guides feel so strongly about the issue that they have formed an 'Inconvenience Committee', highlighting toilet problems and advising where best to powder one's nose. Apparently the toilets at Embankment Tube station are best. Guides are also keen to recommend the National Gallery toilets.

But there are signs things are becoming less of an inconvenience. As the British Toilet Association sits in conference this week, one of its bolder plans to boost the number of lavatories - the community toilet initiative - has been pioneered successfully in wealthy Richmond, to the southwest of the capital.

Marks & Spencer, Waitrose and KFC, plus dozens of pubs, can earn up to GBP1,000 (HK$16,040) in annual payments if they display a blue sign showing the public they can use facilities gratis. Businesses report an increase in custom.

London's most-visited borough, Westminster, is also bucking the trend, hosting more than 40 public toilets, more than were available 20 years ago.

The council has recently installed 12 temporary urinals, two fixed urinals and two telescopic urinals that rise out of the road at peak times on Friday and Saturday nights. It is also experimenting with public-private partnerships which will lease toilets to 'washroom management firms'. The phrase spending a penny needs to be updated, however, as some charge 50 pence a go.

Westminster has also pioneered the first toilet location text messaging system, which, in marketing speak, matches the user and service provider.

Calls cost 25p. Not cheap, but at least it avoids the embarrassment of being caught using a pub or cafe toilet without asking permission.

Dick Whittington would not be pleased. All together now: 'Ooooh nooooo he wouldn't.'