Throughout the year, Zilker Park is disrupted during four large events that occur there annually. These include the ABC Kite Festival, KGSR’s Blues on the Green concert series, Austin City Limits Music Festival (ACL), and the Trail of Lights. The clean-up of ACL ends on Oct. 19, however, annual maintenance begins on Oct. 20.
The process for restoring the park after ACL can take up to a month. In an attempt to revive the grass, the restoration team starts with aeration, a process where a tractor pokes holes across 40 acres to open it up. Next, they use water and fertilizer to help the grass grow. Unlike other years, between the weekends the team did supplemental watering which showed rebound over the week period.
Lots of foot traffic during ACL compacts the soil, which consequently loses the space it needs to hold nutrients. 450,000 people visit ACL each year, on both weekends. Weeks before the ACL festival, the team spends time preparing the lawn, spreading dirt and fertilizer, then aerating and watering the lawn. Water and fertilizer are also key in toughening the grass and then helping it regrow.
Eli Meshbane-Duke, a lifeguard at Barton Springs and senior at McCallum, remembers the state of the area during ACL.
“I worked during one of the [ACL] weekends,” Meshbane-Duke said. “It was some of the lowest turnout I can remember, so if anything, it gives the Barton Springs soil a break. In my experience things returned back to normal remarkably quickly. I was surprised to see Barton Springs unaffected by the festival because of the max influx of people just down the street. An area of Zilker Park is almost always closed to give the grass a chance to grow back.”
Soil disturbance is problematic in all areas but is particularly concerning along environmentally sensitive waterways. Field data were taken on soil erosion issues at 140 points throughout the study area.
Meshbane-Duke also visited Austin City Limits on the second weekend and remembers the change of the ground.
“I remember the grass was much greener and clearly healthier before the festival,” Meshbane-Duke said. “Of course all the trampling led to the grass dying in mass, but that could also be attributed to the turning of the seasons.”
Meshbane-Duke said the area became very dry during the festival.
“I vividly remember all the dust flying through the air and getting in everyone’s faces, even spreading decently past the festival,” Meshbane-Duke said. “It was like the Wild West. I could have sworn I saw a tumble weed. By the second weekend of ACL I’d describe the grass as brown and dry. The grass had been trampled dead, and any remaining green gas was few and far between.”
Pablo Agustin Boeri, Ph.D., is an assistant professor at Texas A&M AgriLife Research and Extension Center at Dallas. Boeri claims post-event recovery is as important as prevention. There are many events at Zilker Park, and appropriate recovery is required to prevent further damage.
“Timely irrigation and fertilization support regrowth and prepare the turfgrass for upcoming stress periods,” Boeri said. “Ensuring that turfgrass recovery occurs before subsequent events is essential for maintaining long-term quality and soil function.”
Boeri proposes multiple different approaches to this recovery.
“Avoiding shaded or already stressed areas, rotating event sites, and monitoring soil moisture are important considerations,” Boeri said. “A proactive management approach, combining proper turf selection, event rotation, soil management and recovery practices, can increase parks’ resilience to public events.”
Large public events such as concerts and festivals can impact park ecosystems and turfgrass health. Stress can occur in the form of temporary structures, such as stages, tents and seating areas as well as from pedestrian and vehicular traffic. These activities alter the turfgrass and underlying soil, often resulting in long-term effects that extend well beyond the duration of the event.
The Austin Parks Foundation is a partner in hosting the festival, and has spent more than $6.8 million for maintenance at Zilker Park over the last 25 years.
Elaine Bohls-Graham believes that the Austin Parks Foundation tries to restore the park to its best ability.
“I think they try to do sustainable practices,” Bohls-Graham said. “It all depends on the audience that’s going to be there and if they want to follow the guidelines and the rules, it’s more successful than if they don’t. I believe that they are trying to maintain it so that it doesn’t become compacted, and that they do try to replace what gets torn up. I think they’re really trying hard to do what is best and that’s just part of our mission in Austin.”
Bohls-Graham also visited the park when she was young, and recalled how it used to be.
“I grew up with Zilker Park being really healthy, it was beautiful, even out in the big area where they do the stages and Trail of Lights and things like that. It doesn’t look like that now as much because they also had tree damage and things like that. They’ve changed the look, but I think they’re trying to restore it and better maintain it that way.”