I was pleased to read this:
"Elaine Smith (Coatbridge and Chryston) (Scottish Labour): To ask the Scottish Government on which ScotRail routes the rolling stock is not fitted with effluent retention tanks.
(S4W-22745)
Keith Brown: The routes on which rolling stock which is not fitted with effluent retention tanks operate, according to the December 2013 rolling stock unit diagrams, are:
Glasgow Queen Street to Alloa, Oban, Fort William, Mallaig and Anniesland; Glasgow Central to Kilmarnock, East Kilbride, Stranraer, Dumfries, Carlisle; Edinburgh to Glasgow via Shotts; Edinburgh to Newcraighall; Edinburgh to Fife
From December 2017 there will be no ScotRail or Caledonian Sleeper franchise-operated rolling stock that discharges toilet effluent on to the track."