A rig drilling a test well at Forty Niner Country Club is raising concerns for trees along nearby Tanque Verde Wash.

A.E. Araiza / Arizona Daily Star

The Tanque Verde Wash, unlike most of its Tucson counterparts, still blooms with yellowing cottonwood and willow trees during autumn’s current peak.

But the fate of some of this vibrant riparian area could be at stake as a far east-side golf course prepares for the possibility of resuming groundwater pumping nearby.

The owner of Forty Niner Country Club golf course, Ron McKenzie, has endeared himself to many area residents since taking it over a year ago, by fixing up a course that the previous owner had allowed to deteriorate dramatically.

Now, however, McKenzie is stirring controversy with Tucson Water officials and others through his plans for a well test that could ultimately bring back larger-scale pumping. Since 2006, the course has instead nourished its fairways and greens with reclaimed water purchased from Tucson Water.

McKenzie has an Arizona Department of Water Resources permit for the test, which should start soon. If the test succeeds, the well would ultimately be used to pump groundwater for the golf course, according to the state permit application. That would require another state permit and a purchase or lease of water rights.

A Tucson Water attorney and a longtime neighbor of the course are worried that new pumping would draw down the region’s shallow upper aquifer and kill many of the big trees.

McKenzie sought to ease their fears in a telephone interview last week.

“All we’re doing right now is drilling a replacement well and testing it. We’re not looking at replacing the city’s reclaimed water. We always use reclaimed water.”

Asked if he will pump groundwater for the course if the test succeeds, he said, “I don’t know ... . That’s why we’re drilling this test well. We’ve made no arrangements to acquire water rights. We’ve talked to some people. That’s about it.”

If he does use that well for the golf course, it would be only to fill his course’s ponds, he said, which for logistical reasons he now can’t fill with reclaimed water when he’s overseeding the course each year. He said he would never match the pumping level that went on in that area a decade ago by the golf course and the city.

The permit application, signed by Forty Niner Country Club General Manager Wendy Cross, says flatly that the well ultimately would be used for the course. McKenzie said, “I haven’t seen that permit (application). I couldn’t tell you what it says.”

Kelley Matthews, who lives south of the country club in the Tanque Verde Valley, said her concerns aren’t eased by McKenzie’s assurances.

“We’re in a major drought, and this area is very fragile,” said Matthews, a valley resident of 30 years. “Whatever groundwater we have should be preserved for the environment.”

The new well would be 85 feet deep, far below where the water table starts at 14 feet deep, the club’s permit application said.

The neighboring wash, besides its cottonwoods and willows, contains one of the region’s few remaining large mesquite bosques, said Thomas Meixner, a University of Arizona associate hydrology professor.

Past groundwater pumping by the golf course, city wells and individual private wells had killed off many of the big trees, but much of that pumping has been reduced or stopped in the past decade.

Since the country club started buying reclaimed water, the wash’s vegetation has grown thicker and greener, resident Matthews said.

“And although it’s gotten drier and the wash has less water than it used to, the (water in the) wash came further down and for longer periods when it did run,” said Matthews.

Protection of the wash’s vegetation is the key reason the city spent $8 million to connect its reclaimed system to the course, said Chris Avery, Tucson Water’s chief counsel. The city also bought many of the assets of the golf course’s water system back in 2003.

“We have a contract with them to be exclusive provider of reclaimed water to the golf course. If they continue to pursue this avenue we will be exploring our legal remedies to enforce this contract,” said Avery. He declined further comment.

Clark Baught, owner of Farwest Pump Co. Inc., which is drilling the well, sees this impending dispute as mainly an economic issue for the city. In the last half of 2012, Tucson Water earned about $187,000 from the Forty Niner course.

“The city of Tucson wants to sell water — it’s not a matter of them running out of water,” Baught said.

Avery, however, said that while economics is a concern, the main reason for buying the golf course’s assets was protecting the wash.

Contact reporter Tony Davis at tdavis@azstarnet.com or 806-7746. Follow him on Twitter@tonydavis987.