Oxfordshire is cleaning up its act with fly-tippers seemingly on the backfoot.

Tougher enforcement - including a network of hidden cameras and more prosecutions - has seen a drop in fly-tipping across the county.

And that comes despite a switch in the city from weekly to fortnightly bin collections that critics said would lead to more people dumping their rubbish in lay-bys and out of the way places.

Two years ago, Oxford Mail reporter Giles Sheldrick took a van to investigate illegal dumping after figures showed flytipping in the county had increased by 60 per cent in a year.

Within an hour of searching Oxford and the surrounding area, he found a television, a DVD player, settee, armchair, patio table, chairs and rotting carpets - enough to create a down-at-heel front room.

A repeat Oxford Mail investigation last week found less flytipping: fewer sites and all we could rustle up was a mattress, two car seats, a small hill of tyres, a couple of carpets and a door.

We visited well-known hotspots in the city and in south Oxfordshire, and while some flytipped waste was found, there was little evidence of illegal dumping within the ring road, apart from the massive illegal dump at Redbridge, which has now grown to 926 square metres.

City council leader Bob Price said: "Our City Works department operates an incredibly flexible and efficient bulky waste collection system and that has made a big difference.

"The free service was restored in 2002 after charges were introduced in 2000 - people know they can rely on it and tell their neighbours.

"Staff at the county council's waste recycling centre at Redbridge allow metals, oil and all sorts of bulky stuff to be tipped off and that has also helped.

"Thirdly, our green waste collection over the past two years has meant that people are putting compostable garden waste in their green bags instead of dumping it at the roadside."

During the year from April 2007 to March 2008 in Oxford there was a fall from 3,516 flytipping incidents to 3,314 - a 5.7 per cent reduction. Overall the county had a similar fall, down from 6,371 to 6,024.

Liberal Democrat Jean Fooks, city councillor with responsibility for a cleaner city under the previous Lib Dem administration, said the reduction confirmed that the introduction of fortnightly waste collections in 2006 had not led to an increase in flytipping, as first feared.

Some councils have used camera surveillance to catch out illegal dumpers and take them to court, where they face heavy fines.

Chris Clifford, of Warwick Street, East Oxford, said: "There are still pockets of flytipping around the city, so I don't think councils should be too self-congratulatory.

"The city council-run recycling points in Union Street and at the big Tesco in Cowley are often overflowing with domestic waste which has just been dumped.

"A decrease in flytipping is a start but there should be a greater number of prosecutions."

Kennington parish and county councillor Bob Johnson said the illegal dump at Redbridge had grown over the past six years, and added: "Unscrupulous contractors have dumped the stuff there over the years and I have got the county council to promise to spend almost £900,000 to remove it in 2010/11.

"There is now a concrete wall around it to prevent more dumping but the material needs to be sheeted over as well."

Flytipping has also reduced in West Oxfordshire, Cherwell, the Vale of White Horse and marginally in south Oxfordshire.

Richard McCrann, a spokesman for Cherwell District Council, said: "The council is taking a stronger and more proactive stance against flytipping and this has led a reduction in the number of incidents over the past three years.

Melanie Mullen, senior waste and recycling officer for South Oxfordshire District Council, said: "A lot of flytipping is household waste - people are still dumping black bags in laybys.

"Staff go through the waste to try to identify the people doing it - there is no excuse when there are weekly waste collections."

During the past year, flytipping incidents in West Oxfordshire reduced by 85, down 11.5 per cent.

In April last year, West Oxfordshire District Council set up an environmental enforcement team to deal with issues such as flytipping.

Patrick Legge, environmental protection team leader at Vale of White Horse District Council, said: "We work very hard to catch and prosecute flytippers. Last year we dealt with more than 600 incidents which cost £35,000 to investigate and clear up."