I no longer go to Escalera but am told by a friend that does go there that it is no longer owned by Escalera. He is just keeping the name because lots of people still go there.
I do get a 50% discount. You have to show your INE card and it is next automatic.
the schedule I have is 30 to 45 m3 increase 24 centavos per m3
46 to 60m3 increase another 51 centavos per m3
61 to 75 m3 increase another 8 centavos per m3
76 to 90m3 increase another 22 centavos per m3
the more you use the more it costs
minimum monthly usage is 15m3 billed every 2 months, so if in 2 months you use 30 or less m3 you are billed 295 pesos.
They only give discounts to citizens as my friend was told.