Petrol pump owners warn that ethanol’s moisture absorption may contaminate E20 fuel.
| Photo Credit: Shiv Kumar Pushpakar
Petrol pump owners claim that ethanol’s hygroscopic nature or affinity towards water is leading to contamination of their E20 stock during monsoons and in the coastal areas since the existing underground storage tanks were designed for conventional petrol, not higher ethanol blends.
These claims come amid videos that have become viral on social media purportedly showing customers collecting what appears to be muddy water, rather than E20, from fuel dispensers. One such video involved a Toyota Hycross car, following which the automaker had blamed fuel contamination rather than any vehicle related malfunction as the car was E20 compliant.
Three petrol pump owners shared their concerns over the roll out of E20 with The Hindu speaking on condition of anonymity as oil marketing companies have instructed them not to speak publicly on the issue.
“The underground tanks that store fuel often have some amount of water due to ingress during rains or moisture or condensation or from the fuel tanker that brings petrol to the petrol pump. Now, when the water content in the entire E20 stock in underground tanks exceeds 0.5%, ethanol binds with water because of its hygroscopic nature or affinity for water. This results in phase separation, where water-ethanol mixture settles at the bottom of the tank, while the petrol forms a separate layer above,” explained an industry veteran.
As fuel is drawn by the dispensing unit from the bottom of the underground tank, some vehicles may end up being dispensed this water-rich mixture instead of E20, pump owners further explained.
“As a result, vehicles may not start, or breakdown after a distance. We come to know about contamination only when such customers come to us with complaints,” said one of them.
They also said that the concerns were compounded in coastal areas where there is sub-soil water which can further contaminate E20 stock if the seals on the underground tanks are not properly in place.
One of the petrol pump owners also expressed fears that underground tanks and pipelines made of mild steel could become more susceptible to corrosion because ethanol’s tendency to absorb water, potentially adding to fuel contamination. Some said OMCs had however replaced seals and washers in petrol dispensing units with neoprene rubber in preparation for E20.
‘OMCs dissuading petrol pumps to have signboards on E20’
Petrol pump dealers also said there was need for creating awareness among vehicle owners in order to prevent disputes at fuel stations. They said motorists should be advised on the need for protecting their vehicles from rain as well as during washing to ensure there is no water ingress in fuel tanks, but the oil marketing companies (OMCs) were actively dissuading them from displaying any informational boards.
“Some petrol pumps had hoardings saying E20 was being dispensed on government order, but OMCs were offended and ordered for them to be removed. They don’t want customers to know even this much,” said one of the petrol pump operator.
Petrol pump dealers said they have been instructed to check underground storage tanks for water contamination three times a day, with the frequency increasing to once every two hours during the monsoon. Many pumps use a dipstick coated with water-finding paste that turns red in the presence of water. If contamination is detected, the dealer informs the oil marketing company (OMC), which deploys personnel to drain the water from the tank using a hand pump.
Dealers, however, said they were unhappy with the financial burden of the process. They pointed out that while they purchase the entire stock of E20 fuel from OMCs, they must bear the losses when any contaminated portion has to be discarded. One of the persons above said he lost 600 litres of fuel recently, while there are others he said who have lost upto 20,000 litres of their stock. They also asked for guidelines for discarding such contaminated water.
Zero tolerance towards contamination: Indian Oil
In a press statement, Indian Oil Corporation Limited (IOCL) said that they have zero tolerance policy towards contamination. It said regular inspections, surprise checks and scientific testing are carried out as part of a rigorous quality assurance system, and that in the past week alone it had carried out 10,000 surprise inspections across its retail outlets, conducted more than 8,500 quality tests and deployed hundreds of special inspection teams to independently verify compliance with quality standards.
“If any instance of adulteration, contamination or violation of prescribed quality norms is detected during inspections or established through customer complaints, strict action is taken against the concerned dealer in accordance with the applicable guidelines and contractual provisions,” the statement added.
Published – July 16, 2026 10:46 am IST
