The campaign aims to tell consumers not to put items such as cooking fats, nappies and cotton buds down toilets and sinks. This was the cause of more than 80 per cent of sewerage blockages dealt with by Scottish Water last year, the company said.
Once disposed into the drainage systems, these items combine to produce a mass of solidified fat and material – so-called fatbergs – which can then block the pipes.
The first phase of the campaign was launched in 2013 and early indications are that there has been a reduction in blockages.
The third phase will also highlight easy ways householders can save water in the home.
Chris Wallace, director of communications, Scottish Water, said: “Blockages in the sewer network are not only costly to Scottish Water, they can lead to real distress when flooding occurs.
“This initiative is a great way of working with customers to prevent blockages from happening in the first place.
He added: “Although Scotland has plentiful resources of raw water, the treatment and distribution of water is very energy intensive and the heating of water counts for a sizeable share of energy use.”