Aiming to eliminate direct discharge toilets from its entire fleet of passenger coaches by 2020-21, Railways has drawn up an action plan to replace them with environment-friendly bio-toilets.

“While 17,338 existing toilets in trains have been replaced with bio-toilets till date, our aim is to equip the entire coaching fleet with bio-toilets,” said a senior Railway Ministry official involved with the project.

According to the action plan, all new coaches would be fitted with bio-toilets by 2016-17, while the retrofitting of existing coaches with bio-toilets will continue.

For the 2015-16 fiscal, Railways has set the target to fit 17,000 bio—toilets in long—distance trains as part of its ’Swachh Rail -- Swachh Bharat’ programme.

Direct discharge of human waste from the existing toilet system in trains causes corrosion of the tracks, costing the public transporter in crores to replace the rail tracks.

The new-age green toilets have been designed by Railways along with Defence Research and Development Organisation (DRDO) keeping in mind the requirements of Indian trains.

The bio-toilets are fitted underneath the lavatories and the human waste discharged into them is acted upon by a particular kind of bacteria that converts it into non-corrosive neutral water.

While the process of fitting 10,500 bio-toilets in new coaches is in progress, the target for the 2015-16 fiscal is 17,000 bio-toilets.

The Railways is also working towards improving the condition of toilet facilities at stations and in trains as it has been receiving several complaints from passengers regarding lack of cleanliness at these facilities.

The official said the aim is to make Swachh Rail the driving force behind the governments flagship programme -- Swachh Bharat Abhiyan.

Railways, which have launched a cleanliness drive across the country, has collected a fine of Rs 4 crore in the last six months against spoiling and littering railways stations across the country.