Brian Dorwart Inducted into NASTT Hall of Fame

The NASTT Hall of Fame is pleased to welcome Brian Dorwart, Senior Consultant at Brierley Associates as its 2024 inductee. The Hall of Fame honors NASTT members who have made outstanding accomplishments and exceptional contributions to the advancement of the North American trenchless industry and NASTT.

As Trenchless Technology techniques were gaining popularity in the US during the late 70s, Brian Dorwart was working in the construction industry as a geologist, geotechnical exploration driller, and construction technician. Immediately following completion of his Master’s degree in Civil Engineering, he started work with a geotechnical engineering firm diving into technical analyses, and management of projects involving geology, geotechnical engineering, underground construction, and geotechnical instrumentation. Dorwart has provided expertise on projects ranging from heavy construction of pipelines, tunnels, dams, and highways, to light industrial buildings and dynamic machine foundations. His area of specialization is the interaction of ground to excavation tools and/or natural environmental processes and ground modification for construction. This specialization has been applied to trenchless technologies including directional drilling, small to large tunnels, soil/rock stability in shoreline protection systems, landslides, during permitting, design, and construction. His management experience includes developing strategies for bid preparation, risk based design, conceptual design, research and development, construction engineering, forensic analyses, and consulting.

Dorwart’s extensive range of expertise in trenchless technologies has contributed to the industry and knowledge base through an understanding of the interaction of subsurface engineering and geology, leaving a legacy of technological advances within the industry and projects throughout North America.

In addition authoring more than 20 papers for NASTT No-Dig Shows, Dorwart has contributed papers or articles to AWWA, GeoStrata, ASCE, ISTT, Trenchless World, UCT, Geotechnical Instrumentation News, Trenchless Technology, DCCA, Tunnel Business Magazine, Geosynthetics, ASTM Geotechnical Testing Journal, US Rock Mechanics Conference, and the Society of Mining.

Upon being told the news, Dorwart responded, “This is quite an honor. I’m honored to just have been considered.” He discussed his commitment to spreading knowledge, getting new engineers excited about trenchless and advancing the profession. “Knowledge is key these days. The more we can pass it around the better. Somebody helped us. Somebody encouraged us,” he remarked. Brian is dedicated to paying it forward having spent a lot of time in the industry, especially in the early 90s as part of the Northeast Trenchless Association and the formation of the Northeast Regional Chapter by helping folks solve problems. “I try to support the young people and get them involved in presenting papers. My name doesn’t need to be on it,” he said. “They’re doing the work and gaining the experience. That’s just part of being an engineer.”

Brian’s induction will be celebrated at the NASTT No-Dig Show on April 16 during the Casino Royale. Purchase your ticket when you register to attend the conference.

Warren Environmental Set to Establish Roots in Georgia with Relocation

[Gainesville, Georgia] – Warren Environmental and Coatings, LLC (Warren Environmental), a leading manufacturer of proprietary epoxy products and patented application technologies, is excited to announce its strategic relocation from Massachusetts to Georgia this fall. This move reflects the company’s commitment to enhancing operational efficiency, expanding its presence, and better serving its Approved Applicator Network.

The new 15,000-square-foot manufacturing facility in Gainesville, Georgia, offers numerous advantages for Warren Environmental. The decision to relocate was driven by several factors, including improved logistical capabilities and enhanced operational efficiency. The location in Georgia will facilitate faster shipments of products, enabling Warren Environmental to better serve its expanding Approved Applicator Network. In addition, the new facility will provide operational efficiencies regarding optimized layout and design, up-to-date infrastructure, and additional space to accommodate the increased production and storage needs.

Company President Brian Brandstetter expressed his enthusiasm about the move, saying, “This relocation represents a significant milestone in our company’s growth. Our new location in Georgia aligns with our long-term goals and enables us to provide our applicators and their clients with quality and readily available epoxy products.”

As Warren Environmental relocates its manufacturing facility, it remains committed to providing the same high-quality epoxy coating system and excellent service that its applicators have come to expect. The company assures all existing and prospective applicators, as well as their customers, that this relocation will have little to no impact on their current operations. The relocation process has been thoroughly planned to ensure a seamless transition without disrupting operations.

The official address of Warren Environmental’s new headquarters is as follows:

Warren Environmental and Coatings, LLC
1596 Fulenwider Road
Gainesville, GA 30507

About Warren Environmental

Warren Environmental is a leading manufacturer of proprietary epoxy products and patented application technologies. Since 1996, Warren has protected or rehabilitated private and municipal clients’ water and wastewater infrastructure throughout the U.S., with safe and effective epoxy coatings for all environments.

For more information about Warren Environmental and its relocation, please visit our website at or contact

North American Society for Trenchless Technology 2023 Innovative Product Award Winners

North American Society for Trenchless Technology Announces 2023 Innovative
Product Award Winners

The North American Society for Trenchless Technology (NASTT) announced the 2023 Abbott Innovative Product & Services Award winners at the NASTT 2023 No-Dig Show in Portland, Oregon. The Abbott Innovative Product & Services Award celebrates companies with a state-of-the-art product or service making a significant impact in advancing the trenchless industry in the areas of rehabilitation or new installation.

The selected winners met the highest-level of standards for each category. Products were judged on Innovation (concept, method, development); Value (need, advantages, cost); and Impact (sustainability, social/environmental responsibility and potential).

“It has always been a goal to bring breakthrough innovative trenchless technology to the forefront of the profession,” said Matthew Izzard, NASTT Executive Director. “The Innovative Product & Services Award is a testament to trailblazers whose skill, ingenuity and vision impact underground infrastructure development and improvement techniques, promote sustainability and protect the environment.”


In the category for New Installation, the award was given to Ditch Witch for its AT120 All-Terrain Horizontal Directional Drill.  Built to boost jobsite uptime, the AT120 gives underground construction operators the power and stability needed to push through tough ground conditions, streamlining fiber, pipeline and utility installation projects. As the largest AT drill in the world, the AT120 improves jobsite efficiency for previous mid‐ and maxi‐size drill owners, as it uses less drilling fluid, resulting in decreased jobsite waste, minimized cleanup and reduced environmental impact. For more information, contact Jeff Davis, HDD Product Manager at or visit

In the category for Rehabilitation, the award was given to Sunbelt Rentals for| PumpSentri, an advanced standalone bypass monitoring system that can fully integrate into a bypass pumping system. PumpSentri Remote Monitor allows for continuous real-time pumping system information to be sent to a cloud‐based platform for data logging system pressure, suction vacuum, wet well surcharge, flow, vibration, and all the engine telematics. This new technology allows for remote monitoring, and the ability to see what cannot be seen in a bypass system in order for the crew to precisely dial in to bypass operations and mitigate any potential issues before they occur. For more information, contact Ladd Gould, National Strategic Customer Manager at or visit


NASTT also honors the finalists in each category:

New Installation

Vermeer Corporation for Vermeer D550 HDD |


CPM Pipelines for BulletLiner SystemTM FFRP |

CPM Pipelines for Acquaint’s Acquarius |

HammerHead Trenchless for HydraSlitterTM |

HammerHead Trenchless for RS BlueLine System |

QuakeWrap, Inc. for StifPipe® |


Sewer AI Corporation for Sewer3D |

Presentations about each product were made at the Innovative Products Forum at the NASTT 2023 No-Dig Show and are available online via NASTT on YouTube. To learn more about NASTT awards, visit The award is named for the late Joseph L. Abbott, Jr., an active NASTT member since its founding in 1990 and a champion of innovation.

NASTT Announces 2023 Outstanding Trenchless Paper Awards – Rehabilitation

NASTT is pleased to announce the winners of the 2023 NASTT Outstanding Trenchless Paper Awards for New Installations and Rehabilitation. These awards recognize excellence by commending authors of the best NASTT No-Dig Show papers each year. The winning papers were presented at the NASTT 2023 No-Dig Show.

Download the winning papers bundle or the full conference proceedings in the NASTT Online Store.

Authors of both papers will give encore presentations at the NASTT 2024 No-Dig Show in Providence, Rhode Island.

NASTT 2023 Outstanding Paper – Rehabilitation

Emergency Trenchless Rehabilitation of the East Don River Trunk Sewer and the Highland Creek Interceptor.

Christopher C. Macey, Global Technical Practice Leader, AECOM, Winnipeg, MB

Bo Pajic, Program Manager, Capital Works Delivery, Toronto Water Division, Toronto, Canada

Kristy Gibson, Program Manager, Capital Works Delivery, Toronto Water Division, Toronto, Canada


About the Authors. The team that put together this year’s winning paper for rehabilitation is comprised of experts with the experience necessary to tackle an emergency situation during the COVID crisis. Kristy Gibson is a Senior Project Manager with the City of Toronto, where she has managed both linear and vertical infrastructure upgrade projects for Toronto Water since 2015. Bo Pajic is a professional engineer and has been with Toronto Water since 2010 and took the lead in developing the City-Wide planned Sewer Rehabilitation Program in 2015. Chris Macey, P. Eng. is a Vice President and the Americas and Global Technical Practice Leader for AECOM for Condition Assessment and Rehabilitation of Underground Infrastructure with more than 45 years of experience. 

“This project is important to showcase to the industry given its complexity and urgency, especially the Highland Creek site due to its proximity to the Scarborough Hospital,“ Pajic noted. “Trenchless methods allowed the repairs to be completed in a more expeditious manner when compared to open-cut replacement, which was critical during COVID.” Macey agrees. “This work was particularly critical and getting it done and getting the message out there means a great deal.” The City staff were also an important part of the team especially Richard Noehammer, William Shea, Garry Boychuk, Adam Zietara, Jian Lei, George Roknic, Irina Vasile. and Sarah Duff. Pajic and Gibson were thrilled to work alongside Macey, who In 2019 was elected to the NASTT Hall of Fame for his work in Condition Assessment and Rehabilitation. “We would like to thank Chris Macey for his steadfast contributions to the City of Toronto’s Sewer Rehabilitation Program,” they said.”As a leading industry expert, his knowledge and expertise on the Program and specifically in the completion of this emergency project was invaluable.”

Abstract. The East Don River Trunk Sewer (EDTS) and the Highland Creek Interceptor (HCI) Sewers are both critical sanitary sewers in designated ravine areas in Toronto, ON. Both sewers were originally constructed in the 1950’s and during the course of 2020 and 2021, they developed surficial sinkholes due to severe loss of ground into defects in the pipe and manhole structures.

The EDTS was a 1200 mm (48”) diameter pipe in very soft soils and the settlement had engaged 12 pipes with a maximum settlement of about 600 mm (2 feet). Its failure would have resulted in the direct discharge of large sewer volumes in the East Don River. The adjacent section had previously failed and showed signs of active deterioration as well due to loss of ground.

The HCI sinkhole was centered over a Maintenance Hole (MH) that was 9 m (30 feet) deep and had engaged 2 -900 mm (36”) pipes and approximately 4 – 1050 mm pipes (42”). The maximum amount of pipe settlement was about 400 mm (16”). Its failure would have engaged a bridge structure and would also have resulted in large sewage flows into the adjacent Highland Creek.

This paper captures the two separate emergency response efforts in 2021 and early 2022, where both locations were uniquely repaired using a balance of external ground stabilization techniques and CIPP lining with minimal ground disturbance. The HCI repair included MH lining and a single tapered CIPP tube shot with 4 different design sections (varying wall thickness and tube circumference).

NASTT Announces 2023 Outstanding Trenchless Paper Awards – New Installation

NASTT is pleased to announce the winners of the 2023 NASTT Outstanding Trenchless Paper Awards for New Installations and Rehabilitation. These awards recognize excellence by commending authors of the best NASTT No-Dig Show papers each year. The winning papers were presented at the NASTT 2023 No-Dig Show.

Download the winning papers bundle or the full conference proceedings in the NASTT Online Store.

Authors of both papers will give encore presentations at the NASTT 2024 No-Dig Show in Providence, Rhode Island.

NASTT 2023 Outstanding Paper – New Installation

The Use of a Geo Pilot Bore to Confirm HDD Feasibility

James Murphy, M.Eng. P.Eng., UniversalPegasus International, Calgary, Alberta

Dan Costello, M.Sc. (Hons), P.Geo., PMP. BGC Engineering Inc., Vancouver, BC

Marty Zaleski, M.Sc., P.Geo, CEG, LEG. BGC Engineering Inc., Vancouver, BC

About the Authors. For James Murphy, it all started back in the summer of 1972 when he was a student working on the Toronto subway tunnel construction project. “I gained an appreciation for soils and soil mechanics,” he said. “This ultimately led to a career in major pipeline design and construction and then a specialization in trenchless technology.” In 2011 the paths of the authors put them on a team working on the TMEP pipeline project which they recognized was going to be extremely challenging from a major trenchless standpoint.  They used their ingenuity to demonstrate that these specific crossings were possible using the Horizontal Directional Drilling technology and would likely be the most cost-effective way to meet the challenges presented by the geography and the geology. “The design of trenchless crossings was a natural extension of the work I do to develop and interrogate geological models, using tools that span geology, geotechnics, and geophysics, Marty Zaleski explained. “The key challenge is making reliable predictions of ground conditions in the context of sparse observation points, which requires that we understand depositional processes and devise new ways of collecting meaningful observations. This is where geologists shine.” The whole team shone brightly in Portland and want to acknowledge Rob Brown, President of Universal Pegasus, Alex Baumgard, BGC Geotechnical Engineering, Manjiri Khare, Project Manager Universal Pegasus for their support.

Abstract. Within the Trenchless Program for the Trans Mountain Expansion Project almost 50 Horizontal Directional Drills (HDDs) as well as all the other trenchless methods were utilized. However due to severe topography and access constraints, there were locations where a geotechnical investigation with a normal number of boreholes would not be able to provide sufficient geotechnical information and even a limited number of holes would be cost prohibitive. Boreholes in some cases would have been hundreds of meters deep with difficult access and site preparation. Also, from a design standpoint, engineering would primarily be interested in whether there are fractures that would be major fluid loss zones or there would be fractures or faults that would produce water that would likely fail the HDD. Therefore, for two long ‘potential’ NPS 36, HDD crossings in mountainous terrain, Universal Pegasus offered up the potential for doing ‘geo-pilot bores’ to confirm the feasibility of using HDD in these locations. From a regulatory perspective, a geo-pilot bore following the HDD design profile is considered part of the geotechnical program provided it does not exit and stops short by 50 metres or more. Exiting the bore would constitute “construction” which has significant restrictions and reporting issues.

A successful geo-pilot bore approximately 1,700 m (5,600 ft) long confirmed the feasibility of the first HDD crossing at Dry Gulch in August of 2021 and a second geo-pilot bore for the Mountain Crossing #3 HDD crossing, approximately 1,600 m (5,300 ft) long HDD was completed in 2022. This paper describes the design, thinking, and construction challenges behind the geo-pilot bore concept with these two examples.