The Lake District National Park, which fought and won a decade-long battle to impose a 10 mph speed limit on boats using Lake Windermere, has now backed this ruling by the introduction of high-tech speed cops. They will be in action well before the 10 mph speed limit covers all the lake in 2005.

Lake patrol rangers are to be equipped with a laser speed gun at a cost of some £4,500 and a jet water-ski boat at almost £7,000. Last year, 94 of the 416 boats registered on the lake were involved in byelaw offences but only five were prosecuted: authority policy is to issue warnings in all but the most serious of cases.