The Piedmont Park Conservancy will dig a second well after the first effort failed to produce one capable of taking care of the park's irrigation needs.

"This means our priority objectives of protecting the trees, Active Oval and the Meadow cannot be achieved without investigating an additional site," conservancy president and CEO Yvette Bowden said in a statement.

The need for another site means that — barring an end to the long-running regional drought — a return next year of the large-scale events now prohibited at Piedmont and other city parks due to watering restrictions is increasingly unlikely.

The new drilling at Piedmont is scheduled to begin by Wednesday, according to the park conservancy, a non-profit that manages the park. The conservancy hopes the two wells will together provide enough water to nourish the park's trees and plants without using the city's water supply.

The park hopes to know within two or three weeks if the second well, to be drilled at the north end of the meadow near the dog park, will be sufficient, according to an e-mail from conservancy representative Darrel McCook.

The conservancy wants to lessen the park's dependence on the city water supply. Because of drought and watering restrictions, dozens of trees have died in the 185-acre Midtown park, according to Chris Nelson, vice president and chief operating officer of the conservancy. Officials also want to protect the health of new turf installed in the athletic fields.

Drilling on the first well began in June at a site near Lake Clara Meer. Testing of the well's output continues, according to McCook, but intial results showed another well will be neded.

The conservancy has permission from the state Environmental Protection Division to drill up to seven wells on park grounds.

The conservancy is paying for the well-drilling project.

In January, the city mandated that no event with 50,000 or more people could take place in a city park. The city acted out of concern that park turf would be irreparably damaged.

Dianne Harnell Cohen, the city's commissioner for parks, recreation and cultural affairs, has said the city would consider bringing those events, such as the Atlanta Dogwood Festival and the Atlanta Journal-Constitution Peachtree Road Race, back to the park if the irrigation needs were met.

However, she said that that is hypothetical and that it would be irresponsible for her to say that those events' organizers should plan a 2009 return.