Decorative pond from the 1982 World’s Fair receives new XR-5® liner.
Name: World's Fair Park
Dates: March 2016
Location: Knoxville, TN
World’s Fair Park in Knoxville, TN, was constructed for the 1982 World’s Fair, where it became known as a premier venue for country and classical music concerts. The park consists of multiple event venues, decorative ponds and a two acre festival lawn. The centerpiece of the park, the Tennessee Amphitheater, reopened to the public in 2007 after it was renovated in 2005.
Fairgrounds facility managers requested the installation of XR Geomembrane’s XR-5® material to replace the preexisting liner that was deteriorating after years of algae buildup. Contractor’s verified Seaman Corporation’s XR-5® geomembrane liner because of its durability, low thermal expansion and contraction properties.
In March 2016, the XR-5® 8138 black liner was installed in large panel segments that were field-seamed together to ensure a secure waterproof seal. Over 60,000 sq. ft. of material was installed around the perimeter of the Tennessee Amphitheater and pond area.
“It is going to be a very good installation and I think the city is going to be very happy with it,” said Felon Wilson, Business Director of Industrial Fabrics. Since the installation of the XR-5® membrane, the world-renown venue has continued to entertain and host events for audiences all over the globe.
To track the ongoing performance of the XR-5 installation, we checked in on this project 18 months after installation and 5 years after the installation. Read on for our findings.
18 Months After Installation
When we checked in 18 months later, we had five key observations:
- There are no leaks reported by the owner, the Knoxville Metro Building Commission. In spite of underwater connections and a layout that was somewhat complicated, all connections are secure. That was a major priority for the installers.
- The liner remains in place. No uplifting is occurring, which would be the result of improperly prepared subgrade. The site was somewhat at a low point surrounded by higher ground, and no springs or other water intrusions had been noted in the past, so dirty subgrade would be the concern. With prefabrication, minimal field seams were necessary which would be a major potential source of leaks and subsequent uplift problems.
- Perimeter battening is secure and has not been compromised by thermal expansion/contraction of the membrane. The XR-5 geomembrane used in this installation has a negligible rate of thermal expansion/contraction.
- There is no evidence of chemical attack in the waterfall area, the point where water treatment chemicals, primarily solid and liquid chlorine-based products, are introduced.
- Inspections are important. The Building Commission empties the pond about twice per year, usually in the winter for cleaning and inspection. Also, the geomembrane installer returns for an inspection once per year.
A geomembrane represents an engineered alternative to natural materials, but like natural materials, there are lots of materials that will "work", but often not many that will work properly. Consider the whole project along with the initial cost. This one is functioning well at the 18-month point.
Five Years AFter Installation
In 2021, we checked in on the project as it was due for pressure cleaning. The cleaning was done successfully, beginning with high-pressure water. Watch a video of the cleaning below.
Our observations during inspection:
- Debris was accumulated and manually removed. This involved foot traffic on the membrane.
- The geomembrane was glossy, flexible and no damage was noted from any of the cleaning activities.
- No chemical attack was noted in the disinfection chemical introduction zone.
- Connections that are normally underwater appeared good. Perimeter above-water battening appeared secure.
The on-site PBA supervisor, Steve Blackwell, noted “the liner has held up very well with no problems.” PBA realizes the advantage of cleaning and inspecting the geomembrane on a continuing basis and noted that cleanout and maintenance were relatively simple. Easy, infrequent maintenance is an important criterion when selecting a geomembrane.
For over 25 years, XR technology has set the industry standard for geomembrane strength, durability and performance. Plus the long record of successful installations containing a variety of harsh liquids has given Seaman Corporation a recognized position of leadership in this very specialized field. XR technology is used in all types of applications including pond liners, secondary containment, floating covers, wastewater baffles and potable water containment.