The City of Roseburg is tucked in southern Oregon’s forested Umpqua River Valley. The community of about 25,000 residents is expanding, and its urban daytime population swells to more than twice that size. Recent years have brought new businesses and restaurants to the area–and they’re all serviced by Roseburg Urban Sanitary Authority (RUSA), which manages over 160 miles of sewer mains and 10 pump stations. 

Facing Off Rainfall, Roots and More

In this environment, RUSA has its work cut out for it. Kyle Bartlett, RUSA’s collection system supervisor and a Roseburg local, explains that the area sees heavy rainfall in the winter months. This rainfall becomes groundwater that creates problems with inflow and infiltration. Roots also present a persistent challenge: Roseburg has been called the “Timber Capital of the Nation,” and its wooded landscape means root intrusions are constant.

In addition, the boom in restaurants has produced complications with fats, oil and grease (FOG) in its collection system.

“Identifying grease with our CCTV equipment is something we’ve been trying to improve on recently,” Bartlett explains. “We’ve been ramping up our FOG program in the last few years. We’re able to track a naughty list of the restaurants that are discharging grease into our system, and check them annually…. If I find some I notify the inspectors.”

“I Didn’t Want To Go Backwards.”

High-quality sewer assessment equipment is essential to identifying these sources of FOG. In 2018, RUSA decided it was time to retire its 10-year-old Envirosight Supervision crawler. Bartlett researched every new system out there, intent on securing the most cutting-edge gear he could find. 

“I didn’t want to go backwards,” he says of his equipment search. 

He looked into Envirosight’s ROVVER X sewer inspection crawler and was impressed with its modern features, particularly its touchscreen controller.

“The touchscreen was really cool to me, and ROVVER X was the only system that felt like an upgrade.”

RUSA quickly invested in a mainline RX130, RX95 and a RX400 for trunk lines. And in the next couple of years, the Authority would also purchase a lateral launch add-on for ROVVER X and a CleverScan manhole scanner from Envirosight.

Envirosight’s newest poster details the causes of inflow and infiltration, or I&I. Inflow occurs when water from aboveground sources enters sewer systems through illegal or faulty connections or openings. Infiltration happens when stormwater seeps through cracks, joints or manholes into sewer pipes. Together, I&I consists of water that does not have to be treated but ends up in a treatment plant anyway. 

When sewer systems work, they’re largely invisible to the public. Wastewater flows, unseen, through pipes from homes, businesses and industries to treatment plants, where it is cleaned and returned to the environment. 

But standing pools of water and foul odor—signs a sewer is not functioning properly—are increasingly common.

Recognizing your collection system is suffering from inflow & infiltration (I&I) is the easy part, but identifying the problem areas and addressing them effectively is where the challenges come in.

It takes more than just general maintenance and repairs to make a real impact on the inflow and infiltration (I&I) entering your sewer collection system. Without a strategic, proactive approach to evaluating and addressing the costly issue, it can feel like an uphill battle.

Sewer laterals often don’t get much attention during regular CCTV inspections. Because homeowners are responsible for their care, they are frequently left off the usual schedule. This can leave a large portion of a collection system un-inspected, un-repaired and ready to cause problems. When laterals do end up on the docket, it’s usually for one of three reasons:

Inflow and infiltration (I&) is a risk in any waste system. Yet in regions with older infrastructure, groundwater and stormwater that enter a sewer system can account for as much as 50% of flow. The cost of this disruption should not be underestimated; in 2014 the EPA reported that wastewater collection and treatment expenses ranged from $2 to $5 per thousand gallons. An annual I&I volume of 150 million gallons would cost between $300,000 and $750,000 per year to transport and treat. Given that even small amounts translate into substantial costs, where should you draw the line on I&I? How much is too much?

Inflow and infiltration (I&I) can be a costly problem for many wastewater systems and pose major risks. How much do you know about inflow and infiltration? Take Envirosight’s Sewer IQ quiz to find out, then challenge your coworkers to beat your score.

When a sewer fails, the solution is seldom cheap or easy. Digging it up can be particularly costly, as well as disruptive to residential customers and road traffic. To avoid this, methods have emerged allowing sewers to be fixed without excavation. These methods are referred to collectively as “trenchless technologies.”

No two sewers pipes are alike. Many differ significantly in terms of size (both diameter and length), pipe material, effluent characteristics, service connections, soil composition and water table. Pipes also fail in different ways: they can crack, leak, settle, erode, corrode and collapse. These failures can be localized, or they can be pervasive. Moreover, the goal of rehabilitation can vary to include:

Like other civil infrastructure in the U.S., many of our sewer, storm and water lines are over 50 years old (BAFuture). One of the biggest issues facing underground infrastructure is corrosion. A study from NACE International estimates the annual direct cost of corrosion for the water and wastewater industry is $36 billion. This cost includes replacing extremely corroded lines; lost water from cracks and breaks; application of corrosion inhibitors, internal linings and external linings; external coatings and cathodic protection.