Tesco and Asda brand water is not what consumers might expect.

Though it is branded as “Just water, nothing added,” the companies have come under scrutiny this week following the revelation that the bottles being sold in stores contain nothing more than tap water.

Tap water costs a third of a penny per litre. An Asda or Tesco two-litre bottle will set customers back 17p.

But Asda and Tesco maintain that their water is not simply straight from the tap. Tesco said that its water is filtered and its labeling accurate. Asda spokespeople also said that the water was treated before being bottled.

Despite the uproar, the supermarket chains have not falsely advertised their wares. No declarations of ‘natural spring water’ adorn the bottles. But consumers are upset, nonetheless, that they have been misled by these trusted brands.