County officials are proposing a $1 million bond project to help preserve the popular nature spot Agua Caliente Park, where the water level at the drought-stricken main pond has withered so dramatically in recent months that about 60 percent of it is now a waterless mud flat and weed patch.

“This week, the pond is 35.5 inches down below capacity. That’s the lowest level we’ve recorded since we’ve been watching it,” said Kerry Baldwin, Natural Resources Division manager for Pima County. The county acquired the site northeast of Tucson in the mid-1980s and has managed it as a park since then.

“The park manager said she’s seen mud in places she’s never seen mud before” in areas once covered with water, Baldwin said. “Probably about 60 percent of the historic footprint of the (3½-acre) pond is now exposed mud.”

The pond’s shrinkage has taken place in spite of the fact that well water is pumped into it daily to augment flows from a spring and rainfall that once kept it full.

“We are currently pumping about 40,000 gallons per day and not keeping up,” Baldwin said.

Likely reasons for the pond’s vastly diminished size include:

  • Prolonged drought.
  • An uncommonly warm winter that increased evaporation.
  • Failure of the hot spring that once fed the pond to produce a regular flow over the past two years.
  • Pumping of groundwater at more than a dozen new wells drilled within a half-mile radius of Agua Caliente since the year 2000.

“Our goal is to give the pond system another 50 to 75 years of life,” said Baldwin, referring to the main pond and two smaller ponds at the park. “Unfortunately, the natural spring system apparently is not going to be a source for that water.”

That’s why county officials are pursuing other avenues to save the pond, which is extremely popular with nature lovers, bird-watchers, walkers and people who have arranged to hold weddings and other events on a small island.

The officials, Baldwin said, are seeking a $1 million bond to pay for measures that could preserve the pond.

“The county bond (advisory) committee will get briefed on the $1 million project at their May 2 meeting,” he said. “We hope they will ultimately support the project.”

The proposal also would need approval from the county Board of Supervisors before it could be part of a future bond election seeking voter approval.

Key elements of the plan include reducing the size of the pond, installing a liner in its bottom to reduce water loss, and re-landscaping the shoreline to eliminate some plants that use excessive amounts of water.

“We would reduce the footprint of the pond from 3.5 acres to 2 to 2.5 acres” to reduce water needs, Baldwin said. “And if we put a liner in about 90 percent of the pond, that would allow us to maintain the water level while putting in a lot less water.”

Leaving about 10 percent of the pond bottom unlined would allow water to seep out if and when the pond reached capacity.

Removing some of the cattails and other plants along the shoreline would further reduce water needs, Baldwin said.


The Friends of Agua Caliente Park, who offer support through fundraising and volunteer efforts, organized a petition in support of the bond effort.

Jim Knoll, president of the Friends group, said that obtaining funding for the planned work might be the only way to save the pond.

“With the ongoing drought and decreased water flow supporting Agua Caliente Park, the main pond is drying up,” Knoll said. “The park is on the National Register of Historic Places, and it’s a worldwide birding destination and a unique community treasure. Without funding support from the county bond program, the main pond will not recover, and the residents of Pima County may lose this ‘oasis in the desert.’ ”

Contact reporter Doug Kreutz at or at 573-4192. On Twitter: @DouglasKreutz