The Woodman Point Waste Water Treatment Plant in Munster, Perth, has experienced deterioration of the concrete structure around its channels due to gas attack.
Fixing the damage was broken into two stages. McRoberts Contracting Services (MCS) were brought in on the first stage of the project, which required the lining of a channel totalling 12 lineal metres.
The success of the first stage saw Woodman Point engaging MCS to continue the work on the second stage. This required work on a further 16 lineal metres of channel with similar damage and included both an ‘S’ bend and four launder channel entries on the PST channel.
MCS were called in to use its patented HDPE lining to restore the damaged infrastructure, which included the floors, walls, and roof of the channel, up to the horizontal deck.
Before the lining could be attended, MCS undertook a thorough cleaning process using high-pressured water jet cleaning of all concrete surfaces, as well as scabbling works to improve adhesion.
MCS used layers of 12 mm high-density polyethylene (HDPE), striped to 25 mm wide and fixed to the perimeter of the channel lining. The process allowed them to extend the lining, including pouring high strength grout behind the lining and existing concrete surfaces.
A minimum of 12 mm of grout was injected into each section using and injection tubes and funnel system. This worked to both secure the lining in place, and to rebuild the existing deteriorated concrete. While rebuilding the internal concrete maintained structural integrity, the HDPE lining also provides corrosion protection.
MSC used an internal bracing and scaffolding systems to stabilise the HDPE lining while the high-density grout was injected and dried.
The entire process was undertaken in stages, lining 2.6 m sections at a time.
The Woodman Point Water Resource Recovery Facility was upgraded in 2020. The upgrade increased the facility’s capacity to 180 megalitres per day and included improvements to its odour control system.
MCS channel lining comes before further upgrades to the Woodman Point’s sludge processing system, which is expected to commence later this year.
By upgrading the system, Woodman Point aims to recover 100 per cent of the biosolids, or ‘sludge’, in the Perth metro region.
MCS have developed a name as leaders in the fields of pipeline maintenance and plastic welding, among others. Its HDPE patented innovations were designed with the safety of staff and clients a priority, and with interest in remaining environmentally friendly and beneficial in terms of cost.
In order to tackle the task, MCS were able to utilise a number of its innovative patents to ensure the safety of its workers and success on the project.
The work is covered by MCS’s 50 years guarantee, which will allow Woodman Point to move into the upgrades to its sludge processing system without worry.
For more information visit McRobert’s website.
This article appeared in the August edition of Trenchless Australasia