ISSUE 3

WIA CELEBRATES 10 YEARS OF SMART

WATER AWARDS

SCIENTISTS FOR A NIGHT: WIA

MEMBERS TOUR AWQC

SCHNEIDER TACKLES TELEMETRY

SOLUTIONS IN WATER

DETECTION SERVICES:

DETECTING THE EDGE OF

TECHNOLOGY

8 Irrigation & Use. Resource Management. Leadership. Planning & Delivery.

Being Fab - Leading the way with GeomembraneAs the nation’s leading supplier and installer of complex geomembrane containment solutions, Fabtech Australia have expertise across a range of applications and with 27 years of experience in the industry, Fabtech have a reputation for delivering critical projects on time and on budget.

A recent example of Fabtech’s success is their completion of the Wattle Park Reservoir Liner and Cover Replacement. This project was integral to Adelaide’s metropolitan water supply, as well as to the broader success of the North South Interconnection System Project, which forms part of the eastern transfer system providing SA Water with the capability to interconnect the southern and northern networks, ensuring security and versatility of water transfer is maintained.

In 2011, with the potable water storage’s peak operational period fast approaching, SA Water contracted Fabtech Australia to carry out the design, site remediation, construction, and commissioning of the new liner and floating cover for the 27,000m² potable water storage.

The storage was an irregular shape and included floor structures and mixers which presented design challenges to achieve a taut cover surface when in service for effective on-cover water and solids management.

A complex central plate design was used with primary and secondary defined sump features. To support the requirement and minimise on site time, the design also incorporated large area segments allowing prefabrication of critical geometry and bulk area segments. A number of liner and cover geomembrane materials were considered for this project. Fabtech selected an unreinforced, high performance, geomembrane material with high elongation performance and flexibility with exceptional UV resistance and Chlorine performance.

The site activities were undertaken during the South Australian summer with daytime temperatures inside the storage above 50 degrees celcius. This necessitated night time working to ensure safe working and weld integrity. As the storage was located in a residential area specific strategies were necessary to manage noise and light pollution.

Following the removal of electrical fencing and other redundant facilities, the existing

liner and cover was cut and rolled into 40 parcels weighing 3 tonne each, then elevated out by crane. To ensure the new lining system achieved the required design life, the concrete basin was remediated where necessary and a protective cushioned geotextile layer installed.

The lining system was required to operate with an Action Leak Rate based on the technical paper, Leakage through liners constructed with geomembrane, Giroud and Bonaparte 1989, and verified with regard to this performance by hydrostatic testing. As repair of any liner defects would be complicated by the need to empty the storage and to work under the installed cover. The completed lining system was validated by electrically testing to ASTM 7003. This process assisted in the lining system being commissioned without the need for any repairs. To facilitate cleaning and maintenance during asset life, the cover design incorporates capability of inflation in addition to the inspection hatches and sampling ports.

Fabtech engineered an industry leading design, featuring a unique active vent system to avoid cover ballooning from air entrapment, as well as an innovative mixing system to enhance water consistency and reduce required chlorine levels, and a cover that functions at all water levels. These Fabtech engineered outcomes not only served as solutions to project challenges, but have also provided the water industry with working prototypes and installation methodologies for use on future water storages.

Fabtech Australia’s installation crew delivered the liner and floating cover installation with minimal disruption to the community and environment, while achieving a project safety accomplishment of nil lost time injuries. The reservoir has been back in service since February 2012, functioning as per the design and client expectations.

For more information on Fabtech Australia head to www.fabtech.com.au.

Who are Fabtech?

- The nation’s leading supplier and installer of complex geomembrane containment solutions with expertise in applications ranging from; landfill containment, floating covers, water storages, gas covers, tanks, and electronic testing, to tailing storages and heap leach pads.

- Delivering geomembrane supply, design and installation projects for over 27 years.

- National client base of Blue Chip customers.

- Extensive track record in delivering complex designs and multi-layer lining systems.

- Positioned to deliver critical containment projects nationwide.

CASE STUDIES