Sinkhole Prevention: Avoiding Costly Repairs
What Are SinkholesIn very basic terms, sinkholes are depressions or holes in the ground. Also known as a sink, swallet, doline, swallow hole or cenote, sinkholes can range widely in size from large to small. Found all over the world, sinkholes are relatively common geological phenomena.
Occasionally a sinkhole may exhibit a visible opening into a cave below. In the case of exceptionally large sinkholes, such as the Minyé sinkhole in Papua New Guinea or Cedar Sink at Mammoth Cave National Park in Kentucky, an underground stream or river may be visible across its bottom flowing from one side to the other.
Why Do Sinkholes OccurSinkholes are depressions or holes in the ground caused by karst processes. Karst processes refer to the dissolvement of carbonate rocks, such as limestone and gypsum, by water and chemicals. As sinkholes typically have no external surface drainage, rainwater stays inside the hole and drains into the subsurface. As the rock is slowly eroded by water percolating down, the rock erodes and weakens creating caves and caverns. The land above this erosion generally stays intact until the rock underneath can no longer support it, resulting in a sudden collapse.
Sinkholes can also form when the existing, natural water drainage patterns are changed. When land surface is changed, for example when a runoff-storage pond is created, the immense weight of the new material can initiate a collapse resulting in a sinkhole.
Sinkholes can also form when natural water-drainage patterns are changed and new water-diversion systems are developed. Some sinkholes form when the land surface is changed, such as when industrial and runoff-storage ponds are created; the substantial weight of the new material can trigger a collapse of the roof of an existing void or cavity in the subsurface, resulting in development of a sinkhole.
Human activity that can trigger a sinkhole through altering water table conditions include;
- Over withdrawal of groundwater
- Drilling new water wells
- Timber removal
- Creating artificial runoff and storage ponds
- Laying pipelines, sewers, water lines, storm drains, etc
- Increased runoff from impervious surfaces such as roads, parking lots and sidewalks
Improperly maintained sewer and water pipes can also trigger sinkholes. Leaks from these pipes may create underground flows that significantly speed up the process of unseen, underground erosion. This erosion can result in surface collapse.
In the case where a pipe is submerged in a body of water, the Deep Trekker DTG3 Remotely Operated Vehicle (ROV) is the ideal inspection tool. Commonly known as an underwater drone, the ROV is built with the same portability as the DT340 Pipe Crawler. The fully submersible ROV can be equipped with a Cutter, 2 Function Grabber and a laser scaler to aid in assessing a maintenance or repair job.
It is often difficult to predict where sinkholes may develop. However, in some instances, areas of high risk due to deteriorating underground utility systems can be identified. Sinkholes in urban areas are often caused by aging sewer pipes and compromised water mains. Water leaks from corroded, fractured or old pipes erode the strata around it and form an unstable void. In addition, activities on the surface such as construction or heavy traffic reduce the integrity of pipes. When a large section of pipe does collapse, the wall structure may pull large volumes of the surrounding soil down with it.
In the United States, Florida experiences some of the highest rates of damage from sinkholes. Nearly $300 million per year is required to repair and deal with the consequences of sinkholes. Filling a hole and restoring utilities, roads, and the landscape can also take weeks or in larger instances, even months.
Sudden Sinkhole Prevention
Municipal utilities often work in junction with road construction crews to unearth areas known to have aging pipes and replace these mains before they become an issue. Digging up crumbling infrastructure on a long street can cost millions of dollars. However, preventative replacement costs less than encountering the sudden costs of ruptured mains.
Proactively replacing structurally failing infrastructure shouldn't be a guessing game. Guessing which pipes may need attention is a risky proposition. Millions of dollars can be misdirected to one street but two blocks over, a water main bursts and causes excess spending and unwarranted closures.
How Can Deep Trekker Vehicles Help Prevent SinkholesAiming to provide solutions for every mission, Deep Trekker makes tough tasks easy. Constantly seeking to develop the most durable, innovative, portable and affordable underwater remotely operated vehicles (ROVs), pipe crawlers and utility crawlers to solve a suite of underwater problems, Deep Trekker is on the cutting edge of submersible technology. When you buy an ROV from Deep Trekker, you buy the team, the ideas, the vision and the support.
Deep Trekker offers three different ROVs, the DTG3, REVOLUTION and PIVOT. The battery operated submersible vehicles are camera equipped to provide users with reliable eyes underwater and can be outfitted with a number of add-on tools and sonar. In addition to ROVs, Deep Trekker also offers the DT640 Utility Crawler. Available with both rubber and magnetic wheels, the DT640 is designed to work in tough underwater environments and equipped with attachments for pressure washing, vacuuming, thickness testing and more.
Perhaps most useful in the case of sinkhole prevention are Deep Trekker’s innovative pipe crawlers. Deep Trekker’s fully submersible, portable, battery operated systems allow users to deploy within minutes.
Deep Trekker pipe crawlers are suitable for a variety of pipes materials including;
- Corrugated steel
- Cast iron
Deep Trekker has two pipe crawlers designed for use in different sizes of pipes; the DT320 mini and the DT340. It is important to note that both crawlers can enter pipes of larger diameters than noted, the diameter is simply the size in which the camera can be centred.
- 8” to 36”
An operator has the ability to inspect the internal structure of the pipes with the pan, tilt, and zoom camera. The live video feed is analyzed on the spot from the lightweight, handheld controller or stored on a DVR or other storage device.
Deep Trekker’s DT340 Pipe Crawler allows municipal utilities to conduct on-going, routine and affordable inspections of their concealed infrastructure before having to dig.
As always, our team of industry professionals is here to answer any questions you may have about how submersible robots can aid in your sinkhole prevention. When you’re ready to get a vehicle of your own, reach out to get your own customized quote.
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