February 2024 Vol. 79 No. 2
Features
Challenges of repairing rural water lines in urbanizing areas
By Cori Sellars
(UI) — Bear Creek Water Association Inc. (BCWA) provides water and sewer services to approximately 50,000 people in a 105-square-mile service area in the rapidly urbanizing south Madison County, Miss., region. The service area is located between the cities of Ridgeland to the south, Canton to the north, Flora to the west, and the Ross Barnett Reservoir to the east. BCWA has nearly 20,000 water meters in its system, making it the second-largest water provider in central Mississippi (after the city of Jackson) and the largest rural water association in the state.
BCWA’s system consists of different sized pipes, ranging from 2 inches to 16 inches in diameter. The majority of the system is made up of 8-inch pipes, but there are also significant sections of 12- and 16-inch pipes. This is because the system includes water wells spread throughout the county, necessitating the use of larger-diameter pipes for efficient water distribution. However, the increasing urbanization and the presence of more underground utilities, such as electric lines and sidewalks, have posed new challenges for BCWA.
“We initially served customers in rural areas, but now our services extend to subdivisions, commercial areas and more,” said Nolan Williamson, general manager for BCWA. “As the area has grown, we have noticed an increase in water and sewer line repairs. In the past, people mainly needed to be mindful of water, sewer and gas lines when digging.
“However, due to the area’s growth, there are now multiple fiber, electrical, cable TV and telephone lines to consider. The use of utility poles for installation has decreased.”
To make repairs, the BCWA team has primarily relied on trackhoes (backhoe loaders) and mini excavators. However, in some environments, using these common equipment fleet staples of most rural water associations can potentially cause additional damage that will need to be addressed.
The biggest challenge today in repairing the water lines is dealing with the obstacles and costs associated with these repairs. With increasing urbanization, simple repairs that used to involve digging a hole, fixing the pipe and filling it back in have become more complicated. Cutting into the ground now risks damaging other utilities, resulting in additional expenses.
Finding another way
According to Williamson, “Ideally, each type of utility would have its own designated area and run parallel to each other. However, that is not usually the case.
“We have numerous utilities that run throughout the county at similar depths and are located just a few feet away from our water and sewer lines. Fiber lines are often positioned on top of our own lines, so when we need to perform repairs, we have to navigate around them. Since each leak is unique, it’s beneficial to have a range of options to choose from.”
BCWA began exploring alternative digging methods several years ago to reduce utility damage during repairs and restoration work.
“We needed a more precise digging method, and we found the solution in Madison County, where horizontal directional drilling (HDD) crews were using vacuum excavators to verify utility locates before drilling,” said Williamson. “The use of small holes and minimal ground disturbance made us realize the benefits of incorporating soft digging methods into our operations.”
While HDD crews use vacuum excavators for potholing, the BCWA team believed it could also use them to help avoid extra work when repairing water lines. So, in 2017, BCWA purchased a Vermeer VX50 vacuum excavator equipped with a 4-inch suction hose, a 1,025-cfm blower and a 500-gallon debris tank. This model is well-suited for the Yazoo clay ground conditions in Madison County and the average depths of buried utilities, which range from 3 to 6 feet deep.
Now when there is a water line leak, BCWA follows a systematic process for efficient repairs. It starts by calling 811, the utility locating service. A team member assesses the problem and shuts off the valves to stop the water flow. While waiting for locates, the team determines the necessary equipment, including the vacuum excavator for areas with multiple underground utilities. Time is crucial once the water valve is shut off, as the water supply to properties has been cut off. The team works quickly to minimize inconvenience to customers and prevent damage to other utilities.
The importance of the vacuum excavator in this process becomes evident. Using it has helped the BCWA team efficiently excavate without damaging other utilities and minimizing the risk of service disruptions.
Efficient repair process
The BCWA team utilizes a vacuum excavator to dig around utilities. This approach helps to minimize the size of the repair working area and helps maintain a cleaner site. By using this method, the team has been able to eliminate the need to repour driveways, resod yards and incur additional costs from damaging nearby utility lines in certain situations.
When digging, BCWA’s crew sets the water pressure at 3,000 PSI, which is typically sufficient for extracting and loosening up the soil without causing damage to any underground utilities. The material is suctioned into the debris tank and hauled off.
“Most of the material we excavate can be reused once it’s dried, since we’re only digging with water,” said Williamson. “That can take some time to dry it out, so we bring in dry material to refill the hole.
“While the process of bringing in other dirt to fill a hole may seem like an extra step, using the vacuum excavator helps us minimize the hole size, so we don’t deal with a lot of material in most cases. Bringing in a little bit of extra dirt is more cost-effective than incurring restoration costs by using larger equipment and having to pile dirt next to the hole.”
Furthermore, using a vacuum excavator provides a more efficient and less physically demanding method and the need for manual labor with shovels. This decision aligns with Bear Creek’s commitment to delivering cost savings to its customers.
Another machine in the fleet
The team still utilizes trackhoes and mini excavators for a large portion of the repairs it makes. But the vacuum excavator has earned its spot in BCWA’s equipment fleet, too.
According to Williamson, the vacuum excavator is not used daily but is regularly employed for potholing utilities and excavating areas where traditional digging methods are challenging.
“The vacuum excavator does not replace the mini excavator but serves a different purpose,” he explained. “It can do things that a mini excavator cannot do. They are two complementary pieces that help us find the best, quickest and cheapest way to make a repair.”
Williamson also acknowledges the initial learning curve, stating, “In the early stages, we had a lot more questions than we do now, and the team at Vermeer MidSouth assisted us every step of the way. The Vermeer dealer ensured that our staff knew how to use the vacuum excavator and continues to support our service and parts needs to this day.”
Vacuum excavators are not only beneficial for rural water systems like BCWA, but also for many municipal systems. With the increasing number of utilities being placed underground, Williamson believes a vacuum excavator should be part of the fleets of municipalities and rural water associations.
Over the past few decades, there have been significant changes in labor, parts and material costs, as well as increased public scrutiny of water outages. As a result, having a specialized machine like a vacuum excavator is important for making repairs around other underground utilities or in areas where restoration costs make other digging methods impractical.
The BCWA team has also recognized the value of vacuum excavators for routine maintenance tasks, such as cleaning around water valves. In fact, a few years ago, when the Jackson, Miss., water system experienced a major outage, BCWA deployed a vacuum excavator crew to assist in locating water valves in the affected areas and restoring the water supply.
“We have gained valuable experience since investing in our Vermeer VX50 vacuum excavator. These machines are not limited to HDD contractors; anyone involved in digging around utilities can benefit from having a vacuum excavator in their fleet,” Williamson concluded.
ABOUT THE AUTHOR: Cori Sellars is a product marketing lead with Vermeer MV Solutions, Piedmont, SC.
FOR MORE INFORMATION:
Bear Creek Water Association Inc., (601) 856-5969, bcwaterms.org
Vermeer Corp., (888) 837-6337, vermeer.com
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