DALLAS (CBS 11 NEWS) – As North Texas faces its third driest winter and summer since record keeping began, cities are urging residents to conserve water—-with very differing approaches.

Residents in the Park Cities love their trees and landscaping. Currently, they have no restrictions as to days of the week they can irrigate—but that could soon change.

Steve Mace, community information officer for University Park, says officials have tried hard to get the word out.

“Our city newsletter that goes to every household has included watering tips, water conservation measures,” he told CBS 11 News.

He adds the city is considering a twice-a-week restriction on its residents. Most of North Texas already does.

Dallas and cities using its system are twice-a-week; so are communities in the Tarrant Regional Water District. Irving is once-a-week; hardest it: cities in the North Texas Municipal Water District, limited to once every two weeks.

“We have experienced really dry weather,” said its spokeswoman, Denise Hickey.

Their lakes are down to scary levels. Weeds cover what used to be shore line at Lake Lavon, now two-years since it was last full, Lake Chapman a 4-year dry spell. Rain a few weeks ago was a pittance. And even getting back the 75-million gallons a day from Lake Texoma when it goes back on line in a few weeks won’t help, Dickey notes.

“The Texoma supply is very high in salt so you have to blend that Texoma water on a 3-to-1 ratio with other water supplies….one part Texoma to three parts other water.”

Lake levels across the region are down, some as much as twelve feet. Lake Granbury is so low that two weeks ago the body of a woman missing nearly 35-years was found in her truck when it finally resurfaced as lake waters receded.

So why are the Park Cities so well off? A deal they struck in 1950 for water in Lake Grapevine; they get first dibs there. But University Park’s public spaces have actually cut water use by 30% through new smart metering technology, according to Mace. “The devices check wind speed, moisture content and whatnot. The benefit is that controls the amount of water that is put into particular watering zones.”

There is concern at the North Texas Municipal Water District that it needs significant ran soon. “While we’ve had some rain inflows and some rain events over the last couple of showers we’ve had they’ve really had no impact to our water supplies,” said Dickey.

She cautions it might have go to its option of last resort: water for only human consumption and for firefighting. None for lawns, trees, or other landscaping.