Jacksonville Wastewater Utility Works To Seal Their System In Hopes Of Eliminating I&I And SSOs

Rehabilitation and outreach efforts are playing a big role in the Jacksonville Wastewater Utility’s battle to eliminate I&I and SSOs.
Jacksonville Wastewater Utility Works To Seal Their System In Hopes Of Eliminating I&I And SSOs
Thea Hughes, general manager of the Jacksonville Wastewater Utility in Jacksonville, Arkansas.

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Jacksonville is in central Arkansas, just off I-40 about 12 miles northeast of Little Rock. It’s not a heavily industrialized area, and the majority of the wastewater utility’s flow comes from residential sources. But with many pipes over 60 years old, some going back to the 1930s, and an average 50 inches of rain annually, SSOs and I&I were causing problems for the Jacksonville Wastewater Utility as early as 1980.

“That’s when we got serious,” says Bob Williams, engineering construction manager for JWU. “We started looking at where that I&I was coming from. What we found was contributions from both pipes and manholes, with manholes typically the worst offenders.”

And so in 2000, JWU began their continuing efforts, now about two-thirds complete, spending to date some $18.5 million on rehab and replacement. Overflows from I&I have been reduced from 27 in 2009 to zero in 2014, a significant decrease. Since 2008, I&I has been reduced on average by 45 percent, with up to 63 percent on some lines.

Jacksonville’s problems

The main issue was simply the age and condition of their pipes and manholes and the resulting I&I and SSOs. Their original two treatment plants used old technology and were being increasingly overwhelmed by daily loads.

Some of that I&I is coming from private residences through pipes on the owners’ property, likewise from sanitary tee clean-outs with caps that have been dislodged or removed and not replaced. Residential contributions are difficult to measure, but based on specific instances encountered they add an easily avoidable load to the collections system. Many homes in the JWU service area are at least as old as the city’s pipes.

Jacksonville discharges stormwater directly without any processing into Bayou Meto, a small tributary of the Arkansas River. Processing would involve a huge cost they’d obviously prefer to avoid, and Jacksonville wants to keep their system split.

“That’s a separate department from ours, and they have to monitor their own effluent,” says Walton Jay Summers, JWU collections system manager. “That started about 2002 when they applied for an NPDES permit to use Bayou Meto for stormwater. To date, their effluent is still within specs. The only stormwater we have to deal with is what gets into our system through I&I.”

Their Class C soils (clay and soft rock) are susceptible to heaving and subsidence — not a good thing when a lot of your pipe is clay or concrete. Topography within the service area varies in elevation by only around 100 feet, so gravity lines are possible, but 14 pump stations are still required. Gravity lines with the requisite slope are limited in depth for practical reasons.

Jacksonville has a warm, humid, temperate climate with hot summers and no real dry season. The cold season lasts on average from late November to late February with freezing temperatures averaging 30 percent of the year. Trenching can be done in winter as the depth of frozen soil is never more than a few inches. Snowfall during this same period is even less an issue, with an average of only 4 inches annually.

Still, it’s hard to trench in wet Class C soil. With an average annual rainfall of 50 inches and an average depth to groundwater from 0 to 20 feet, more often than not they are digging in mud. This can be done safely using approved trench-shoring practices, but is an impediment to what would normally be an easy job.

JWU’s solutions

With 177.5 miles of aging pipe, 3,500 manholes and 14 lift stations, the obvious solution was a full system inspection, repairing what they could and replacing what they couldn’t.

JWU does a lot of their work in-house but subs out pipe bursting to Horseshoe Construction of La Porte, Texas. “We did our first pipe bursting in 2000, and since that time we’ve used only two contractors for that work,” recalls Williams. “Initially, we used the Heller Company from Hot Springs, Ark.”

Likewise with their CIPP projects where contractors are drawn from local sources, Williams explains, “Our contractors have to go through the usual bid process, but if we’re happy with their work the contract has an option for us to renew them for another four years.”

Most of the pipe going in around new construction is PVC or HDPE. For pipe that’s being replaced, what’s already there presents some constraints. If they can make plastic work, that’s what they’ll put in. The existing clay and concrete pipes just haven’t held up in their Class C soils.

For the manholes, which are mostly in-house projects, JWU uses any of a number of products, all cementitious compounds. They’re still comparing efficacies and haven’t yet settled on a specific brand.

“When you have to do bursting into a manhole, there’s usually considerable reconstruction needed, so we make that work part of the pipe bursting process,” Williams says. “That allows our own crews to handle the more straightforward rehabs.”

Manhole rehab was started back in 2008. Since then JWU has seen a reduction in I&I from between 29 to 63 percent with an average of 45 percent, and that’s with only two-thirds of the manholes done. SSOs caused by I&I have also been reduced from 27 in 2009 to three in 2013 to zero in 2014 (as of December).

“We’re addressing I&I from private residences with our service line program,” says Thea Hughes, JWU general manager. “It’s actually been in effect since the early ‘90s, but we’re pushing it more now. Once an I&I issue is identified, we require the homeowner to make the needed repairs at their own cost.

“We provide a letter and diagram explaining the problem along with suggested fixes. They have 90 days to make those repairs or we shut off their water. If they can’t afford it, we provide a loan program through our local HUD office to help them out.”

So JWU is now getting more of the wastewater and less of the rainwater into the treatment plant.

Outreach and education

JWU maintains a website that contributes to their success. On their home page, prominently displayed, are three important links for customer education:

  • Can The Grease
  • Water’s Worth It
  • Wipe Out Wipes

Can The Grease explains alternative disposal methods for household grease and advocates allowing the grease to cool and solidify in cans or cartons for later delivery to the landfill with other household trash. Commercial establishments are required to use grease traps. Compliance has been very good across both sectors.

“In 2011, for example, over 60 percent of our service calls were related to grease blockages in the main,” Summers says. “And it cost the citizens over $19,000 to clean those up. In 2014, we got that down to $3,000 to $4,000.”

The Water’s Worth It section, created by the Water Environment Federation, makes more of an intellectual appeal:

Clean water is critical to sustain life, yet we take it for granted. The world’s water supply is finite. Water is a valuable resource that can be recovered and reused if wisely managed. Future generations are relying on us to find innovative and holistic ways to ensure adequate and safe water supplies. … It’s worth your respect, your effort, your passion, your health and your loyalty. Be as good to water as water’s been to you.

Wipe Out Wipes addresses the issue of sanitary wipes that are often advertised as being flushable, but in practice are not. “Manufacturers have guidelines for being able to use that label, but all that really means is they can be flushed,” notes Hughes. “It says nothing about the ability of the product to break down once it’s in the lines. It often ends up getting caught on roots or other intrusions and wrapping around pump motors.

“What we’re finding is that these things make it into our pumps and can cause mechanical problems that are costly to fix. This is happening all around the country and all around the world. Can The Grease has been extremely successful, but we’re really struggling with this wipes issue. Our slogan has only been in effect for two years, but we’re hoping that if we continue to push it, it’ll eventually catch on.”

The road forward

JWU is not on a rigid completion schedule. They do what they can within their budget each year. “We’re looking at probably another 10 years to wrap this all up,” says Williams.

Fortunately their pump stations are in good shape, as is the treatment plant, so JWU will continue to focus their resources on pipe and manhole infrastructure.

Regular maintenance on the pump stations and treatment plant also tap into their budget, but they hope to lower those costs through their Wipe Out Wipes and Can The Grease educational outreach programs.

“We’re doing a good job with that outreach, seeing improvement every year, and probably pushing it harder than a lot of cities,” says Hughes. “Grease and ‘flushable’ wipes are a problem all over the country, so I hope others can learn from our success. We’ve already been contacted by several cities in Arkansas who want to learn about our programs, like coordinating HUD loan assistance for service line repair by homeowners.”

The JWU educational outreach also extends into area schools. Just last year a local high school student won first place at their science fair for a project investigating how “flushable” various types of wipes really are. JWU helped with that research. Her project was featured as a poster board at the Water Environment Federation Technical Expo & Conference held in New Orleans last October.

JWU has yet to establish an internship program for students interested in pursuing a career in water management, but hopes to in the future. They are deeply involved with the Arkansas Water Environment Association’s Young Professionals Committee, a statewide association, with a JWU staff member serving as chair of the YPC.

The YPC is working with schools to attract students to their profession. As with many utilities, the “graying of personnel” is an issue at JWU. Attracting the number of qualified replacements needed to offset attrition is an ongoing battle.

“I’d say our work on reducing I&I is about as good as it can get,” notes Williams. “We’ve really been aggressive about that, and it’s paying off in many ways. That applies to city mainlines and private service lines. I feel really good about where we are now and where we’ll be a few years down the road.”


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