Pine Bluff, located in the northern Bayou Bartholomew region in Southeast Arkansas, boasts over 57,000 residents. The Bayou Bartholomew is a protected watershed running roughly 300 miles from Pine Bluff, Arkansas south to Louisiana near the MississippiRiver basin. Accepted as the world’s largest natural bayou, the one million acre watershed is home to between 117 and 130 species of fish and half of all Louisiana’s known mussel species, at least three of which are federally listed. These populations make it the second most diverse stream in North America.

The Bayou is also home to mixed forest and bottomland hardwoods that date as far back as 1200 years, according to the Bayou Bartholomew Alliance. Residents and citizens are proud of the area and always mindful of new ways to protect the valued area, keeping wildlife and habitat safe for future generations. These concerns had to be addressed when it was discovered that Pine Bluff’s underground sewer piping system needed rehabilitation. 

On days with heavy rain, the city of Pine Bluff wastewater treatment plant was seeing an increase in the amount of water entering the treatment system. Infiltration was allowing rain water to seep into the wastewater treatment system. While a normal day saw an average 14 million gallons running through the treatment system, the amount nearly doubled on days with heavy rainfall. Working overtime to meet demands caused excessive wear and tear, frequently causing at least one or two of the pump stations to fail during each downpour. Pump station failures averaged anywhere from $2,500 to $10,000 for repairs and labor costs. The 48 total pump stations could not handle the excess wear and tear as they were forced to pump 24 hours a day, 7 days a week. Additionally, residents had poor drainage during the rains and frequently complained of backups.

Something had to be done to address the overload on the city’s wastewater system.

Choosing a Solution

Ten thousand feet of underground pipeline was identified for rehabilitation to tackle the problem. Additionally, a 3,300 linear ft. section of 18-inch diameter pipe surrounding the 52^nd Street pump station needed special attention. The city had been pumping swamp water out of the pump station for nearly six months due to its location in a wetlands swamp area that was inaccessible to digging. 

As uncontrolled removal of trees would have been detrimental to the ecology of the bayou, Pine Bluff’s Wastewater Utility General Manager Ken Johnson decided to use cured-in-place pipe (CIPP) to fix the deteriorating pipelines for the entirety of the 10,000-ft. project, providing economies of scale and making removal of the trees along lines serving the 52^nd Street pump station unnecessary.

Insituform Technologies, Inc. out of St. Louis, Missouri would manage all aspects of the project from tube manufacture to field installation. CIPP tubing would be installed without digging, as the tube could be inserted and extracted from manhole to manhole. The tube would then be inflated and cured using hot water. The finished product would provide a leak free and structurally sound pipe-within-a-pipe.

The choice to implement CIPP sat well with community members and bayou-enthusiasts, who considered the project to be a positive, proactive measure that would cut down on future failures and costs. The project was implemented as part of a larger capital improvements program outlined by the Utility’s Infrastructure Committee, consisting of employee participants and David Dean, who serves as Utility Operations Supervisor.

Derwood Smith, Chairman of the Pine Bluff Public Works Committee, was especially confident in the decision, “I trust any project in which Ken Johnson is involved. He is a great department head and leads a great team.”

The cost of the project was paid for by a 17% sewer rate increase that was implemented over a three-year period starting in 2005. Before the rate hike was put into place, residents were educated as to the benefits to the city and underground infrastructure. While met first with apprehension, the community eventually came on board to support the rate increase. Today, the average sewer bill in Pine Bluff comes in at around $16 per month.  Infrastructure improvements are on plan for the next 5 years at the estimated cost of $3.5million.  

A Project with Results

Upon completion of the project, improvements were apparent and immediate. Prior to CIPP installation, on any given 24-hour day without rain the pump station along the wetlands would receive 17 to 20 starts per pump with an average of 10.5 hours of run time per pump. Now a normal day is estimated to average 12 starts and 6.5 hours run time per pump.

In some extreme cases, it used to take pump stations three days to make up for heavier rains. “With the completion of the CIPP this station will get to a normal state within 3 hours instead of 3 days after a heavy rain. This is a great improvement to what we have seen in the past when it comes to wear and tear on the pumps.” Bruce Lee, Pump Station Supervisor.

There were other benefits as well. In 2001, the city of Pine Bluff experienced 330 sewer main line stoppages. In 2007, that number decreased to 108. Before, each of these stoppages had cost anywhere from $500 to $1,000 to fix. That adds up to a repair savings of over $100,000 per year.

A Working Partnership

The success of the project was in part due to the working relationship of all those involved. Randy Hansbrough, a Business Development representative for Insituform, said that Insituform crews were in and out of each manhole every day and completed the project, doing their best not to disrupt the lives of Pine Bluff residents.

Looking back on the project, Smith was extremely pleased with the way the project was implemented and the lack of disruption to residents, “People didn’t even realize a project was going on due to the fact that the process didn’t block the streets. Insituform always made sure every question was answered and got work done as quickly as possible."

Smith added, “This project was really proactive on the part of our wastewater utility department. I can definitely see us engaging in more work like this in the future.”