CIPP in Henderson, Ky.
November 22, 2011Historic Henderson, Ky., — a scenic Ohio River city that was once home and artistic inspiration to famed naturalist John James Audubon — is making a name for itself today in a new, less apparent way.
One problem this city of 29,000 has faced in recent years is water pollution, resulting partly from Henderson’s dependence on an aged, badly deteriorating combined sewer system that was constructed in segments beginning in the late 19th century and continuing through the 1960s.
Combined sewer systems — called so because they transport rainwater, domestic sewage and industrial wastewater all in the same pipeline leading to treatment plants — can be a source of many community headaches. In Henderson, what sometimes happened was this: During periods of heavy rainfall or heavy soil saturation, the flow periodically exceeded the system’s capacity. The sewers would then overflow, carrying a blend of domestic waste and rainwater into creeks and rivers, having a negative impact on aquatic life and water quality.
As water quality studies demonstrate, this thorny issue is in no way unique to Henderson. In fact, in the mid-1990s, the EPA identified nearly 800 cities in the United States that were using combined sewer systems (CSOs). What sets Henderson apart is its remarkable determination to find an up-to-date, affordable solution for the long term, a solution that would minimize disruption above ground and, most importantly, provide cleaner, safer water to the community.
Henderson’s city leaders knew that achieving these goals would require extensive planning and research, a process they kicked off in 1994, shortly after the EPA issued remediation guidelines.
From the beginning, the city has led the way. According to Tom Williams, director of engineering for Henderson Water Utility, Henderson was one of the first small cities in Kentucky to complete a submission for a long-term control plan; an overall budget of $39 million was established at that time. In addition, beginning in 1995, Henderson went to work to separate sewer lines, a process that required installation of new pipeline, as well as renovation of existing lines.
Henderson has made significant progress in the intervening years and now has separated approximately 60 percent of the system, greatly reducing the number and severity of overflows and improving water quality. In comparison, most other cities of Henderson’s size are just beginning the process of writing their long-term plans for remediating combined sewer issues and have made far less progress in system corrections.
SAK Construction was selected through a bid process in 2010 to take on a key aspect of the long-term plan: the $2.3 million Downtown Sewer System Rehabilitation project, which required cured-in-place pipe (CIPP) capabilities and careful coordination with the thriving businesses in the area to minimize disruption.
SAK is led by industry veterans Jerry Shaw, president, Tom Kalishman, chairman, and Robert Affholder, vice chairman. Headquartered in the St. Louis, Mo., area, SAK Construction is a privately held pipeline rehabilitation and tunneling contractor, with gross revenues of more than $70 million in 2010, up from $31 million in 2009. SAK currently has projects in 25 states for pipeline rehabilitation using CIPP and is an Aqua-Pipe licensee for drinking water mains.
The Henderson sewer project was divided into two phases. The first phase was to install necessary new sanitary sewer and water lines in the 16-block downtown area; the second was to use CIPP to rehabilitate the old sanitary sewers and convert them into separate storm water lines. Ultimately, the project had to meet the requirements of the Henderson Water Utility’s long-term control plan, which is part of a consent judgment between the City of Henderson, the Kentucky Division of Water and the United States Environmental Protection Agency (USEPA).
SAK Construction started work in June 2010 and completed the project in early October 2011. In the process, the contractor renovated 18,736 lf of sanitary and storm sewer pipeline, 8 to 48 in. in diameter, using SAK’s CIPP process.
The Downtown Henderson Project
Working in downtown Henderson was an unusual opportunity for SAK Construction to be part of a carefully planned effort to retain the historic flavor of a community while bringing its water and sewer system into the 21st century.
In 1986 — nearly a decade before the EPA issued its guidelines for remediating combined sewer problems — the city launched a “Downtown Henderson Project” with the help of the National Main Street and Kentucky Main Street programs affiliated with the National Trust for Historic Preservation. The main thrust of the Henderson project was to revitalize and promote the city’s historic business district while preserving its unique character.
The Downtown Sewer System Rehabilitation Project was conceived to complement the 1986 Downtown Henderson Project, which meant that there was a high level of care for preserving the look of the streets and buildings while making every effort to minimize disruption to traffic and businesses.
Overcoming Challenges for Effective Solutions
Each infrastructure project is unique to its geography, terrain and other factors. The Henderson project was no exception.
One of the primary challenges was to mitigate disruption to traffic in the downtown area during necessary periods of cut-and-cover construction. To expedite the CIPP process in areas where larger openings in the streets were necessary, SAK effectively used a steam-curing method on the majority of small- to medium-size diameter pipes. This method decreased cure time significantly while delivering the same high quality end product. In addition, SAK scheduled work at night, when possible.
As a result, the work installing CIPP on a sewer segment was often completed in only eight to 10 hours, with minimal disruption to traffic and business activities. The SAK team, comprised of Tim Bussen, project manager for rehab operations, and Jason Laney, general superintendent for the Central Region, provided effective communication during all phases of the project. SAK prides itself in having superintendents who “wear many hats” on each project in which they are involved, including not only running the field operations for the crews on that specific project, but also assisting in management of the overall project. The Henderson project required extensive work from numerous subcontractors on jobs such as manhole frame and cover replacement, bypass pumping, manhole rehabilitation and top hat installation. SAK Construction considered it beneficial to have a general superintendent onsite to ensure the project went smoothly.
Industry and water quality experts note similar pipeline-related issues such as in Henderson, are on the rise in cities nationwide due to America’s aging infrastructure and growing population. Collapsing, malfunctioning or inadequate water mains, sanitary sewers and storm sewers cause a variety of serious problems and threaten the water supply in many communities.
Henderson Water Utility has taken a proactive approach to improving its water system. The completion of this project will provide the downtown area with a sewer system that is “sealed,” and resistant to many of the problems common in aging infrastructure throughout the United States.
Jerry Shaw is president of SAK Construction.