Trenchless Pioneers is a special monthly series, sharing with readers the trailblazers who made their mark on the trenchless industry.
In trenchless circles, when discussions turn to manhole rehabilitation, it’s easy to pick Bill Shook as one of this sector’s longstanding proponents and key pioneers. Shook was first introduced to trenchless technologies in the early 1980s while he was a partner in a water and sewer supply company in Iowa. In 1984, the company entertained the idea of buying the Insituform license for Michigan.
“I got really excited because I saw trenchless as the wave of the future for replacement of old water and sewer systems. Replacement and repair by digging up old sewer systems wasn’t something that cities could afford,” Shook recalls. “I saw trenchless methods as an opportunity. Though we didn’t buy the license, I grew determined to watch for other opportunities.”
In 1986 Shook met Carroll Trimble in Arkansas. He had just invented a system for trenchless replacement of manholes. This method poured a new, one-piece, concrete manhole inside the old one. Shook was so impressed with this system that he sold his interest in the supply company and formed AP/M in Johnston, Iowa. Shook and Trimble improved and patented the new manhole system and named it Permaform.
AP/M licensed Permaform to specialty sewer contractors who would erect the forms inside the old manhole and then pour a high-strength concrete into the 3-in. gap between the form and the existing manhole wall.
“Prior to our system, the only rehab work on manholes was plugging leaks with chemical grout or applying thin coats of a sealing slurry,” Shook says. “Nothing was being done to structurally rehab or to replace them. Permaform became a whole new cost-effective and permanent solution to deteriorated manholes.”
Education Through Conversations
By this time, Insituform was leading the way in trenchless renewal and AP/M followed by educating cities and engineers about its manhole solutions. Shook and his late wife Phyllis traveled the open road for months at a time crisscrossing 48 states to meet with consulting and city engineers.
“Most of my conversations would start by asking an engineer what kind of problems they had with the manholes. Everyone we spoke with agreed that their manholes were in poor condition, but they were not doing much about them,” Shook says, adding that the owners weren’t doing the work because replacement was costly and disruptive. “That’s when we showed them our methods of replacing without digging or disrupting.”
With rapid acceptance of the cured-in-place pipe (CIPP) system, owners had a cost-effective way to repair their sewers. However, cities soon realized that sealing the pipes only transferred infiltration problems downstream to manholes. This gave AP/M’s applicators many opportunities to worked closely with CIPP contractors.
When AP/M realized that not all manholes needed a complete replacement, it invented its Permacast system whereby its SpinCaster uniformly compacted a structural liner of specialty concrete to the prepared interior to reinforce and seal the old manhole. Its network of certified applicators grew, and work expanded into Canada, Europe and Asia. AP/M continued its extensive testing program at Iowa State University’s Spangler lab. At the same time, it continued to develop and patent improvements that led to its Cor+Gard coating system, also applied by its SpinCaster, and to the invention of the ConShield additive for protection against biogenic corrosion from hydrogen sulfide gasses and its CentriPipe system for SpinCaster application of large diameter sewer pipe and culverts.
“I saw myself as an educator, not a salesman. AP/M was, and still is, all about helping engineers understand the problems in their sewer system so they could choose the best available solutions. We never stopped learning from our customers and other trusted sources like Trenchless Technology magazine, NASSCO, NASTT and BAMI, which similarly emphasized education,” says Shook. “The more we shared our solutions, the more other companies strived for solutions and the more competition grew and the more the trenchless industry benefited. For us, competition bred excellence.”
A Legacy Built
When asked to reflect on his legacy, Shook quickly shifts the focus to his team at AP/M. Keith Walker, Joe Cherry, his wife Miriam and the support staff made AP/M successful and that legacy lives on. Shook is quick to add that the skill and integrity of AP/M’s network of licensed applicators continues its standard of unmatched customer satisfaction.
“It has been a great experience to be on the leading edge of one sector of the trenchless industry,” he says. “AP/M’s legacy of excellence, innovative solutions and customer satisfaction is everything I ever hoped to pass on.”