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Cost-effective, long-term solution for rehabilitating earthquake-compromised wastewater laterals and decreasing their vulnerability to future seismic events

Although several years have passed since the Christchurch, New Zealand 7.1 magnitude earthquake of September 2010 and the deadly 6.3 earthquake of February 2011, it may take another five to ten years to replace and upgrade the hundreds of miles of gravity-fed, clay-pipe wastewater laterals in the city and surrounding…

CSG Drilling and Well Servicing: Workforce 18 Month Outlook

In 2013 Energy Skills Queensland produced the 20 year workforce plan for the CSG to LNG industry in Queensland (2014 - 2034). This research identified that the CSG drilling and well servicing sector is likely to experience steady long term growth, with the workforce expected to peak at approximately 7,000 workers in…

Design of HDD Installations Using American Design Standards and Locally Manufactured Polyethylene Pipe

A measure of success of a Horizontal Directional Drilling (HDD) project was once simply pulling the pipe through to the other end of the bore. With improvements in installation technology and contractor capabilities, this should now not be an issue. A measure of success in 2015 for an HDD pipe installation is that the…

HDD Installation of Pressure Sewer Pipeline in Mine Subsidence Areas

In this study, impacts of mine subsidence on the structural and hydraulic performance of polyethylene pipe in pressure sewer applications were investigated. Structural safety of PE pipe against mine subsidence was investigated and different design safety factors were considered for different methods of installation.…

Horizontal Directional Drilling (HDD) Technology Advancements to Mitigate Environmental Issues and Reduce Carbon Footprints

Drilling fluid is essential for completing any horizontal directional drilling (HDD) installation of pipe, duct or conduit. Drilling fluid – commonly known as “mud” – is composed of water, bentonite or other additives. Fluid carries cuttings out of the bore hole, and lubricates and strengthens inside walls of the…

How Long Do We Expect Spiral-Lined Pipes to Last?

InfinitPipe : Developing a Revolutionary Onsite Manufactured Pipe

Pipelines have been traditionally constructed in short 20-40 feet (6-12 m) long segments. The pieces are shipped from the factory to the job site and stored on site until they are joined together. This process leads to delays in projects due to the time required to build the pipe segments, and high transportation…

Innovative Water Main and Drainage Rehabilitation Techniques

An introduction to techniques that have been pioneered in Northern America, that are new to not only New Zealand but pretty much the rest of the world. The main focus is on watermain pressure pipeline relining / rehabilitation and gives and explanation of the system, its benefits, development, how it is designed and…

Jacked Box Culverts Under the Main Rail Line at Wiggins Island

Microtunneling on a British Army Base in Gütersloh, Germany

On the British Army base in Gütersloh, Germany, the basements were regularly flooding due to the high groundwater table. When the base was originally constructed, industries in the area were booming and the groundwater was used for cooling purposes, keeping the water table at an artificial level. As the manufacturers…

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Orakei Main Sewer Rehabilitation

The Orakei Main Sewer, varying in size from 525mm circular to 2.4m x 1.5m egg shape, was originally constructed in 1910, and runs from Avondale, via Herne Bay and onwards to Hobson Bay, a total of over 8 km. A 250m section of egg shaped concrete block construction 2.4m x 1.5m runs under the Stanley St motorway on…

Pipeline Rehabilitation of Deteriorated Stormwater Conduits in Sydney

Urban stormwater systems are gaining increasing focus from utilities and asset owners throughout Australia. Sydney is the oldest urban settlement in Australia and with a correspondingly aged stormwater network, much of it dating back to the early 20th Century. Accurate records are not always available and many of…

Queensland Urban Utilities Presentation

Real Time Network Level Utility Mapping Using Massive Array Radar

The commercial, safety and community benefits for using Ground Penetrating Radar (GPR) in the detection of underground assets, in particular utilities, is well proven. Currently most GPR surveys are typically carried out by hand pushed units using either single or dual frequency systems to confirm and/or locate…

Rehabilitation of Large Diameter Pressure Water Mains in Hong Kong – a Case Study

Repair of large diameter pressure water mains is always a big challenge. In Hong Kong, a large diameter pressure water main is usually a trunk main serving a big area with a large group of people in a large region and is usually laid under busy roads. Such conditions impose many constraints to the related pipe repair…

Relining of water mains with a Kevlar reinforced composite lining system

Safer Tunnelling Through Technology and Innovation

Smoke and Mirrors: Which Condition Assessment Techniques Work?

The assessment of condition of water mains has become increasingly important in Australia. Several technologies, including remote-field technique (RFT), near-field technique (BEM), ultrasonics (UT), linear polarisation resistance (LPR) soil testing, pressure monitoring and pipeline coating surveys have been…

Stifpipe : Frp Sandwich Construction for Repair of Pressure Pipes and Culverts

Repair of corrosion-damaged culverts and pipes is a challenging task. This paper describes the development of a new type of pipe that can be used as a slip-lining solution for such applications. Unlike conventional pipes, the wall of StifPipe® is constructed of a lightweight honeycomb that is covered on both surfaces…

Structural Rehabilitation – Working in Difficult Environments

With a significant amount of the Australian rail infrastructure approaching 50 years of operational activity the industry is facing an upgrade to accommodate the increase in traffic and load. Designers and contractors are under constant pressure to program and resource the construction work which is very often in…

Taking Advantage of Pipe-String Buoyancy During Long and Difficult HDD Installations

Horizontal Directional Drilling (HDD) is one of the oldest ‘new installation’ trenchless technologies in use today and continues to rapidly grow and develop. HDD contractors are successfully completing ever-longer and evermore-challenging bores when installing water and wastewater pipelines. This is a function of the…

The Renewal of Water Mains Using Trenchless Cured in Place Pipe: a Sustainable Solution

For years now, there has been a sustainable way of renewing drinking water mains. The use of cured in place pipe (CIPP) allows owners to reduce the emissions of greenhouse gas and contribute greatly to the reduction of lost water or unaccounted for water. Furthermore, earthquake prone regions of the world are now…

The Use of Cathodic Protection for External Corrosion Protection of Pipelines – the Experiences in Hong Kong

The common on-line rehabilitation methods for mild steel pipelines, such as protective coating and lining, usually provide protection from inside the pipes. In such a case, corrosion of the pipes can still continue from outside the pipe, leading to its eventual failure. Therefore, internal protective coating / lining…