They will also have to obtain an online permit beforehand if they want to use Cambridgeshire County Council's nine tips, including those at Alconbury, Bluntisham and St Neots. The move is designed to combat the unlawful dumping of trade waste at the sites where there has been a 20 per cent increase in rubbish being collected by the authority. It believes the permit scheme, approved by the council in May, will better enable it to regulate the use of vans and trailers at the sites, helping to ensure that only household waste goes into the tips. Councillor Mathew Shuter, chairman of the council's highways and infrastructure committee, said: "We're seeing more and more pressures on our household recycling centres (HRCs) - between 2012\/13 and 2016\/17 there has been a 20 per cent rise in waste collected at them - and this increases the pressure on our already strained budgets. "We want to prevent unlawful trade waste being disposed of at our HRCs, which is ultimately at a cost to the council tax paying residents of Cambridgeshire." Cllr Shuter added: "With population growth and changes made by neighbouring authorities affecting us, now is the right time for us to bring in a scheme that will not only address this issue but to allow us to monitor who uses our sites and ensure we can cope with rising demand on the service." From October, householders who want to use one of the HRCs with a van or trailer will have to get an online permit in advance and they will be limited to 12 trips a year. For bigger household and garden jobs, trailers measuring five feet in length, excluding the tow bar mechanism, and containing up to 570 litres, will be exempt. Additional staff will be available to help at the nine sites for the opening months of the scheme.