2005 Trenchless Technology Person-of-the-Year: David Bennett

In both the realm of nature and the realm of construction, a strong foundation is needed to help things grow. A building needs to be rooted in the ground before it can reach any great height, just as a tree must have strong roots in order to grow tall. It is often said that a successful business and career is the same way in order to maximize your potential, you must have a solid background and a foundation of knowledge, wisdom and integrity.

However, just as roots provide both strength and support for a tree, so too do partnerships and friendships help to grow and nurture a career. Its something upon which Dr. David Bennett, recipient of this years Trenchless Technology Person of the Year Award, puts great emphasis.

I would not have accomplished much at all had it not been for the support and collaboration I have received over the years, says Bennett. I appreciate this honor, Im grateful for it, but I dont feel I deserve it. I havent accomplished much at all on my own; Ive had so many people help me every step of the way, so many who gave me opportunities and took a chance on me. I will be forever grateful to those people.

While Bennett may be humble about his accomplishments, his friends and associates point out his many contributions to the trenchless industry. Dave Bennett and his business partner, Kimberlie Staheli, have been involved in the design and oversight of numerous challenging trenchless projects that, in my opinion, have stretched the envelope for typical construction through the use of innovative and intuitive solutions, says Dr. Sam Ariaratnam, a professor at Arizona State University. In large diameter directional drilling and in microtunneling, hes done a tremendous amount of work to advance the industry and the capabilities of the equipment. Hes really promoted the trenchless industry strongly and that makes him such a deserving trenchless Person of the Year.

I think hes brought a lot of leadership to the industry, says Dr. Tom Iseley, one of the founding members of the Trenchless Technology Center (TTC) at Louisiana Tech University. One of the things that is really important to the trenchless industry is geotechnical engineering, and I think hes brought a lot of leadership, understanding and education to our industry.

Grounded in Research
Bennett first became involved in the trenchless industry through his work with the U.S. Army Corps of Engineers Waterways Experiment Station, when he became involved with the landmark Construction Productivity Advancement Research (CPAR) program. In 1991, I had never heard the term trenchless technology, even though I had been extensively involved in underground construction since 1975. I was fortunate enough to meet Tom Iseley, and we crafted a proposal to do large-scale field and laboratory research investigating a wide variety of trenchless technologies such as microtunneling, directional drilling and pipeline rehabilitation methods, he says. The research was financially supported by trenchless technology firms and the Corps in a unique cost-sharing arrangement that worked to benefit all participants. There had never been a trenchless research effort in the United States approaching the scale of this program before, and really, there hasnt been anything like it since. We learned so much during that period and had a lot of fun. I became infected with Toms enthusiasm for trenchless. So I would have to say that meeting Tom Iseley and conducting the CPAR trenchless research program was the first big career-changing event I experienced.

The second event and one with even more lasting long-term career impacts was meeting Kimberlie Staheli at No-Dig 1994 in Dallas. I was immediately impressed with her self-confidence, energy and vision. At the time, she was too young to know that she didnt know it all. She believed, and eventually helped me realize, that if you could visualize something, and were willing to work hard, you could achieve it, Bennett continues. At the time, I was a plodding, methodical, detail-oriented geotech-geek, who had already exceeded the few modest goals I had set for myself, and didnt quite know what I wanted to be when I grew up. We formed Bennett/Staheli Engineers a year later, in 1995.To this day, eleven years later, I am still grateful and a bit awed by Kim. Together, we have built a trenchless consulting practice where it is still fun to come to work every day. We work with the finest bunch of people in the business. They keep me on my toes and test me every day.

Iseley says that Bennetts work in the CPAR program was integral to its success. At the time, he had very limited knowledge of trenchless technology and microtunneling, but as he learned about it, the more interested he became. Really, the success of the CPAR program was largely a result of the energy and effort he put into it, says Iseley.

Many of the research results generated in the CPAR program were eventually published in the CPAR Guidelines for Trenchless Technology, with co-authors Dr. Les Guice, Louisiana Tech University, Staheli, and Salam Khan. The American Society of Civil Engineers (ASCE) Standard Construction Guidelines for Microtunneling, published in 2001, borrowed heavily from the CPAR Guidelines. Follow-on field research in HDD led to the publication of Guidelines for Installation of Pipelines beneath Levees Using HDD, co-authored with Staheli, Hugh ODonnell and Tim Hurley.

More recently, the Horizontal Directional Drilling: Good Practice Guidelines, sponsored by the HDD Consortium, was published. Bennett co-wrote the Guidelines with Ariaratnam and Casey Como. We worked closely with the HDD Consortium, but David was able to bring a lot, particularly in the geotechnical aspect of this industry and how important geotechnical considerations are to HDD and all trenchless construction methods, says Ariaratnam. The HDD Good Practices Guidelines is the basis for a highly successful two-day short course sponsored by NASTT and Consortium members that is taught four to six times each year.

Both Bennetts CPAR research and the subsequent guidelines would eventually have a far-reaching impact on the entire trenchless industry, according to Staheli. They impacted the ASCE standards, theyre impacting how the state of California is permitting its directional drilling, impacting how specifications are being written for microtunneling in the states of California, Oregon and Washington. Theyre having huge impacts. To me, the biggest thing to advance the trenchless industry was his dedication to his research and resulting publications, she says.

Martin Cherrington, considered to be the father of directional drilling, has worked with Bennett/Staheli Engineers on a number of projects. He says that Bennetts research has also helped the industry in other ways. I think theres one major thing that perhaps has gone unnoticed for a while. Thats his effort of trying to provide guidance to keep from fracturing out. Thats been the nemesis of HDD, in a way. Fracturing out of the borehole is a big problem and has liability tied into it, and I think Davids R&D work has been a major contribution to the industry, he says. Being able to reduce that fracturing by means of being able to know that there are excessive pressures in the hole and being able to do something about it; thats a major contribution.

Branching Out
Since its founding in 1995, Bennett/Staheli Engineers firm has gone on to become trusted and sought-after for trenchless projects of all sorts and sizes. I look at Bennett/Staheli as a specialist in trenchless construction, not only directional drilling but pipe jacking and tunneling and so on, says Cherrington. There are always a few people within any category of activities, such as art, science, or professional disciplines that stand out from the rest. Take trenchless construction. It is rare that I find people who can really see in the ground to evaluate the state of the physical conditions. Even more rare are engineers who have that ability to present a practical design for the owners needs, as well as a design that has constructibility for the contractors. David has that ability to see the nature of the problem and has a good understanding of the contractors needs to be able to come up with a design for the owners, as well as the contractors, to construct it.

One of the things that were known for is working on challenging river crossings, says Staheli. However, Bennetts abilities are not limited to one technique or specialty. One thing about Dave Bennett is that he has been involved in many trenchless applications, so he has a wide breadth of experience in many different trenchless technologies. When he works on a project, he doesnt have just one tool in his toolbox.

In addition to citing his technical expertise and experience, Bennetts colleagues are most impressed with his integrity, dedication and enthusiasm for his projects. Bennett explains that he has a basic philosophy for each job that he approaches. You identify the risks, and, if at all possible, you avoid them. If you cant avoid them, then you craft a solution that mitigates them and reduces those risks.

It was this philosophy that brought him success while he was working on the Beaver Water District Intake project in northwestern Arkansas, a project that he describes as being the most challenging and rewarding project he has worked on in 30 years. We were a sub-consultant to Montgomery Watson Harza (MWH), and we were asked to help determine the best way to build a new intake to triple the water capacity for Beaver Water District, Bennett says. The original intake was built in the lake before the lake was impounded, so it was built in the dry. That was in 1965; in 2001 it was an important recreational and water supply lake, and we couldnt ask the Corps of Engineers to drain the lake while we built the intake.

What we found, working together with Don Spiegel and the staff at MWH, is that a combination of drill-and-blast and microtunneling offered the safest, lowest risk and most economical alternative, he continues. We were very fortunate to be entrusted by a great owner, Beaver Water District, prime engineer, MWH, and proactive contractors, including Garney Construction (general contractor), Michels Pipeline (microtunneling) and Dykon Blasting (shafts). The execution of this job was essentially flawless, and the contractors deserve a lot of the credit. I would love to do another intake project if they all go as well as this one.

Dorian Modjeski is the director of water and wastewater for TBE Group, Clearwater, Fla., and has worked with Bennett on a number of projects. He says its a combination of academic knowledge, a desire to learn and a dedication to hands-on experience that makes Bennetts projects so successful. He gives projects his full attention, and you can count on him. When he says hes going to do something, hes going to get it done. He always makes himself available. Hes so enthusiastic about that work. Hes always honing his knowledge, and hes always applying that knowledge to every project.

Staheli says that she and Bennett consider this approach essential to ensuring a quality project. We believe that its important to stay involved in the construction as much as were involved in the design. If you dont follow your designs through to construction and you dont follow through with construction management, you do not learn if your designs are working, she says. You dont learn where to improve. You dont learn where the problems are. You just dont get the necessary feedback that you need to continually improve and stay on the cutting edge. By having that dedication to practical construction applications, we are able to continuously evaluate how the construction is going forward and apply the lessons learned to advance our designs.

Giving Back
As demonstrated through his research and projects, Bennett has always been a forward thinker and is someone who wishes to give back as much as he can to the profession that has been so rewarding to him. I try to give something back through my involvement in NASTT, ASCE and other organizations. Its true that I benefit from these associations, but I like to think that I participate to try to give something back. Thats one of the main reasons Im involved with training and teaching activities. I enjoy the interaction; its very rewarding, he says. I learn something new every time I teach a class. I hope Im still learning the day I die.
Most of Bennetts volunteer work centers on education, and while he is pleased by the quality of students who come from trenchless technology university programs, he also believes there are improvements that could help the industry grow even more in the future.

There are at least two areas that I think need attention. One is that we have a severe lack of experienced, skilled craftspeople for operating microtunneling equipment, directional drilling equipment and the other trenchless technologies that require skilled, experienced people, he says. There really isnt any focused university or community college programs that I know of that are addressing this issue. There are certainly some short courses and there are dedicated professors who are doing a good job training students in fundamentals with some exposure to trenchless technology, but their efforts and short courses alone cant meet the can meet the demand. I think theres a need for more focused, longer-term training programs for skilled operators. I think community colleges are best suited to provide this type of training, but the vision and financial support must come from the trenchless industry and volunteers.

The other problem I see in general in our universities in the United States is that we have a lot of very bright students who go all the way through school, get their bachelors degree, get their masters degree, get their Ph.D.s and then start teaching. Theyre bright people, but whats missing is they havent gone out and worked in the industry and the business to understand what truly works and what doesnt and go back and apply those lessons learned. That was one of the things that made the University of Illinois at Urbana-Champaign so special to me, when I was conducting my research on microtunneling jacking forces and settlements. My Ph.D. advisor, Dr Edward Cording, and almost all of the professors in geotechnical engineering also consulted and conducted practical research, and could relate to underground construction. They walked the walk. Just like everyone who graduated from the University of Illinois civil engineering program, I had fundamental theory grounded in the observational approach pounded into my head. I couldnt practice differently if I wanted to.

There is no doubt that in the years to come, Bennett will continue to share his knowledge and expertise with the trenchless industry and will continue to be a driving force in its development. As long as hes kicking and he keeps up his enthusiasm, I think the industry is going to gain a lot from this guy. I see no end to it, says Modjeski. When I speak with Dave Bennett, its always with a lot of enthusiasm and high expectations. He never seems to be bored talking about the work, and hes always excited about bringing something new out on the table to make sure this industry enhances and improves itself.

Katherine Fulton is editorial assistant for Trenchless Technology