The City of Tulsa is warning that if water usage Monday surpasses 197 million gallons, the mayor will implement voluntary water use restrictions.
The City's water treatment plants can pump out 210 million gallons per day. Sunday, the city used 198 million gallons.
It was the highest single-day use so far this summer.
"So if we top that amount today - and with this heat it's a possibility- we'd ask for voluntary restrictions," said Bob Bledsoe, City of Tulsa.
Voluntary water rationing means customers would be asked to limit outside watering to the hours between midnight and noon every other day, based on odd-even address numbers.
"If we use more than 204 million gallons for two consecutive days, those restrictions would become mandatory," Bledsoe said.
It's the same situation the city was in about the same time last year - when Tulsa asked people to cut back for more than a week in early August.
If water use tops reaches 210 million gallons per day for two days, watering would be restricted to the hours between midnight and noon every other day and with the use of a hand-held hose only.
If usage grows higher, then outside watering could be prohibited.
City officials say Tulsa has not issued a mandatory water rationing order in at least 10 years.
The demand for electricity is following the same cycle - with the peak demand coming during hottest time of the year.
"We're nearing the same situation at about the same time as we did last year," said Stan Whiteford with Public Service of Oklahoma. "We set a new, all time peak demand record on August 3 of 2011."
PSO says Tulsa's peak demand is tied to air conditioning, and the peak comes on hot weekdays between 4 and 7 p.m.
Last year, Tulsa's supply of electricity was enough, but PSO is still asking people to cut back.
"We really would like to encourage people to use energy wisely right now. Keep energy conservation in mind, not just for their own lower bills, but to ease the strain on the system," Whiteford said.
Last year - the power company asked people to really cut back because there were some equipment problems in smaller cities that PSO serves.
So far this year, they've not had any similar problems.