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Mechanism of Mud Overflow in Inclined Boreholes During Horizontal Directional Drilling and a Critical Mud Pressure Model

There are numerous considerations during Horizontal Directional Drilling (HDD) operations. Research provides new knowledge to address such considerations. This paper offers a critical advancement in the field of HDD by addressing one of its longstanding challenges, mud overflow in inclined hole sections. By…

Meeting TRGS 519 Standards: Efficient and Safe Asbestos Cement Pipeline Rehabilitation

This paper presents a trenchless method for rehabilitating asbestos cement (AC) pressure pipelines using a low-emission relining system. The approach eliminates pipe removal, minimizes hazardous fibre release, and complies with stringent occupational safety regulations, particularly TRGS 519 (Technical Rules for…

Modern Jacking Pipe Design and Liners: Optioneering for Longevity, Safety, and Sustainability

Modern jacking pipe design has evolved to meet the increasing demands for cost efficiency, durability, and risk reduction in trenchless pipeline installations. A critical aspect of this evolution is the selection of appropriate liners, which play a key role in enhancing structural performance, corrosion resistance,…

Moss St Sink Hole - Repair of Collapsed 12 m deep EggShaped Brick Storm Sewer in Victoria, BC

This paper is a case study outlining the complexity of addressing a sink hole caused by the collapse of a 12 m deep, 1275 mm x 850 mm (H x W) egg-shaped brick storm sewer on a narrow residential street in the City of Victoria. This storm drain is part of the City of Victoria’s 150-Year-Old Brick Sewer Storm Drain…

Navigating Unforeseen Utility Conflicts in Microtunneling

This paper examines a microtunneling project disrupted by an unexpected Bell 360 utility conflict, offering insights into lessons learned and strategies that ensured successful project delivery. Bell 360 Utility is a vital component of Bell Canada’s fiber optic network, providing high-speed and secure connectivity…

No-Dig for Water Supply Construction in One of Finland's Oldest and Most Valuable Parks in the Center of Helsinki

The paper explores the tunnel project by the Helsinki Region Environmental Services Authority, crucial for improving central Helsinki's water services. This newly designed tunnel facilitates the separation of the existing combined sewage system, thereby reducing network flooding and wastewater overflow to sea…

Northwest Inner City Upper Plateau: North America's Largest Diameter Microtunneling Project

In December 2022, the City of Calgary completed the largest diameter microtunnel in North America as part of the Northwest Inner City Upper Plateau Separation Project. This 765-meterlong tunnel, designed to manage stormwater runoff from the Upper Plateau, was developed in response to major flooding events in the early…

Optimisation of Temporary Works in Tunnelling – Key Lessons Learned Over the Past 15 Years in New Zealand

Abstracts should be limited to 250 words maximum. Temporary works play a critical role in the success of tunnelling projects and can often be the deciding factor for contractors in winning or losing contracts. However, their importance is frequently underestimated by clients during project commissioning. This paper…

Optimizing DOT Asset Management: From Field Data to Actionable Insights

Departments of Transportation (DOTs) and Municipalities are under growing pressure to manage large, aging, and complex transportation networks. From drainage systems to guardrails, signs, lane markings, and roadway conditions, effective asset management requires a data-driven, fieldinformed approach. This paper will…

Optimizing Recycled HDD & NDD Muds for Trenchless Utility Installations

This paper relates to recycling HDD and NDD muds, and how they can be optimized within the work site by using the drilled geology within the fluid and re – using the native sand and soils for pipe bedding and final surface reinstatement. A project to renew 1.2km section of 125mm pressure watermain within the Central…

Precision and Safety in Microtunnelling - Automating Control Measurements

PRESERVING CASPER’S INFRASTRUCTURE: A LARGEDIAMETER TRENCHLESS PIPELNE REHABILIATION PROJECT

This paper presents a project overview to rehabilitate a deteriorating large-diameter wastewater interceptor sewer using trenchless cured-in-place pipe (CIPP) for the City of Casper, WY. This project restored critical portions of the City’s main wastewater interceptor system for the next 100 years. The pipeline, known…

Pressure sewers – comparative performance assessment of rehabilitation technologies, in Germany

Pressure sewers are difficult to inspect and trenchless rehabilitation alternatives to their opencut replacement tend to only be used in situations where excavation is not possible – under rivers, canals, roads, rail or other infrastructure. German network owners have been keen to better understand the capabilities…

Raleigh Water Upsizes 8-inch Gravity Sewer to 12-inch Via Pipe Bursting

Raleigh Water, North Carolina, experienced a sewer main break on their 8-inch concrete pipe gravity sewer located in a major thoroughfare. This case study will examine the process of upsizing that 8-inch concrete pipe gravity sewer to 12-inch High Density Polyethylene Pipe (HDPE) via pipe bursting along a major city…

Reduced Peak Wastewater Flows by 23% Through a Nineyear Gravity Sewer Lining Program

The City of Cocoa (city) is located on the eastern side of central Florida just south of Cape Canaveral. The city maintains a service area that contains roughly 1,891 manholes, 85 mi (2,031 segments) of gravity mains, and 53 sewer basins. The city operates the Jerry Sellers Water Reclamation Facility (WRF), which…

Relocating the Dufferin Sanitary Trunk Sewer from under the G. Ross Lord Reservoir

Inflow and infiltration (I&I) are a common problem faced by municipalities regarding their gravity sewer collection systems, as well as the burden the additional flow has on downstream treatment facilities. I&I is typically from groundwater around the pipe, but for the Dufferin Sanitary Trunk Sewer (STS), the G. Ross…

Revolutionising Water Infrastructure: Australia’s First Installation of Saertex-Liner H O

Maintaining potable water pipes is critical to water authorities and asset owners worldwide to ensure safe, hygienic transportation of water to cities and communities. When accessibility challenges and the need to minimise environmental and community impacts make replacement difficult, trenchless rehabilitation…

Right first time - the German approach to quality assurance of cured in place pipe (CIPP) lining of sewers Iain A Naismith

This paper explains the development of Quality Assurance approaches to Cured in Place Pipe (CIPP) lining for gravity and pressure sewers, evolved over past 25 years with German sewer network owners, by the not-forprofit IKT – Institute for Underground Infrastructure. It particularly highlights where publicly available…

Shaping Tomorrow’s Pipes Today: CIPP Lining of Elliptical HDPE in Omaha

The 6th and Leavenworth Grit Facility effluent sewer is a 40” diameter HDPE pipe constructed in 1977 that traverses 820 feet from the grit facility to a diversion structure near the banks of the Missouri River in Omaha, NE, see Figure 1. As part of a larger grit facility project, inspections of the effluent sewer were…

SmartCover Helps Water Utilities Optimise Sewer-Collection Systems

This paper explores the integration of real-time, satellite connected remote monitoring technology in sewer collection systems to address growing challenges such as capacity constraints, inflow and infiltration (I&I), hydrogen sulphide (H₂S) corrosion, fats, oils, and grease (FOG) blockages, and climate-induced storm…

Snowy 2.0 – Marica Road West HDD: Engineering Innovation in Extreme Terrain

The Marica Road West Horizontal Directional Drilling (HDD) project is a critical component of the Snowy 2.0 renewable energy initiative in Kosciuszko National Park, New South Wales, Australia. The project involved the design, drilling, installation and securing of three separate 2,240 metre long, 340 millimetre…

Striking a Balance in the North: How Edmonton Gets the Most from Its Water Transmission Main Condition Assessment Program

Edmonton, with a population of 1.4 million, is North America’s northernmost major city. The weather is below freezing for a third of the year (the coldest day in 2024 was -47°C (-52°F)), compressing the construction season and creating competing priorities. EPCOR, the region’s water and power utility, budgeted over…

Structural Design of GRP Jacking Pipes

Glass Reinforced Plastics (GRP) jacking pipes are now very commonly installed throughout Australia and New Zealand. These pipes are supplied with a very large range of stiffness classes, but design methods are not well established or well understood. This paper examines how the stiffness class should be selected based…

Subsurface Utility Engineering (SUE) on a 23% Slope

Infrastructure development in topographically challenging and urbanized regions such as British Columbia’s Lower Mainland demands a high level of precision and risk mitigation. In areas like White Rock, where terrain can exceed a 23% slope, conventional utility investigation methods fall short. This paper presents a…