FARMERS dipping or showering their sheep in Worcestershire this spring are being reminded by the Environment Agency to take particular care not to pollute rivers, streams and groundwater.

The agency has worked with sheep dip producers and farmers to reduce pollution incidents and is keen to ensure the downward trend continues.

Extra vigilance is needed in using the new synthetic pyrethroid (SP) dips, which are 100 times more toxic than organophosphorus (OP) dips.

Some dips are so potent that just letting sheep cross a ford when still wet from dipping can result in the death of all life in the watercourse for several kilometres.

Using common sense, careful management and best practice guidance is the simplest way to avoid a problem during the dipping season.

The agency offers the following advice:

l Dipping baths should not be used if they have cracks or holes and drain holes should be sealed.

l Mobile baths, dipping baths and showers should be at least 50 metres from any well or spring and 10 metres from any drain or watercourse.

l Sheep should be kept in drain-down pens until they stop dripping and drainage should be directed back to the bath.

l Freshly dipped sheep should not be returned to fields where they can access streams or cross fords until fleeces are dry.

l Used sheep dip should not be tipped into sewers, septic tanks or drains. It should be spread on land where it cannot run off into rivers, streams or groundwater.

l Under the Groundwater Regulations 1998 disposal of all spent sheep dip needs a written authorisation from the Environment Agency. Application packs can be obtained from any of the agency's offices.