The bus routes that a trebling of the mayoral precept could help pay for across the county have been revealed. Cambridgeshire and Peterborough’s Labour mayor, Dr Nik Johnson, wants to increase his portion of the council tax bill so that an average Band D taxpayer would pay £36 this year, up from £12 last year, when the charge was first introduced. The Combined Authority board will meet today to discuss the move, which is expected to be approved, despite some Conservative opposition. The precept rise would also allow bus fares for the under-25s to be capped at £1, the mayor has said. The tax wi…