YORKSHIRE'S rivers are getting cleaner.
But efforts to maintain the good record should not be eased up, says a Government minister.
Official figures show 90% of the region's rivers were considered good or fair in 2002 for chemical quality, a 14% improvement since 1990.
A section of the River Colne at Slaithwaite is rated top class.
But, in a rare blip on the regional picture, Crimble Clough, which runs into the same river from Pole Moor, is rated as poor.
Environment Minister Elliot Morley said: "Substantial improvements have been made in river quality in Yorkshire and the Humber in recent years.
"But we need to step up efforts in tackling the more challenging factors that hit water quality.
"For instance, more needs to be done to curtail agricultural pollution and pollution from multiple sources in urban areas." Mr Morley said officials were developing extra methods to deal with these problems.
Improvements in the biological quality of the region's rivers have also been recorded, with 90% graded good or fair, compared to 81% in 1990.
The Environment Agency said environmental work by Yorkshire Water had been a major factor in the improvements.
Over the last five years, the company has achieved an 80% fall in pollution incidents.
As well as improving its waste water treatment works, the company is spending £200m to upgrade about 1,000 sewer overflows in a three-year programme.
The work is designed to reduce the risk of toilet-related litter - such as soiled sanitary products, condoms and cotton buds - finding its way into rivers.
Yorkshire Water director of waste water Graham Dixon said: "Even though we have seen further improvement in the quality of Yorkshire's river water we are not complacent.
"We are continuing with the massive programme of investment, improving many of our assets that may impact on the environment," added Mr Dixon.