The ROV for Inland Surveys and Inspections: Water Tank Inspection

CASE STUDY: "Who has been Swimming in Your Drinking Water? "

In the dark of the tank, Rich Faulk pilots the tiny, yellow robot through the water. With its two headlights beaming, the 8-pound sub heads down a 3-foot wide section of standpipe. Colonies of corrosion that look like a coral reef wave out from the interior steel like a scene in Titanic. The tank Faulk is inspecting could have been the place you got your last glass of drinking water.

Who has been swimming in your drinking water? Ask Rich Faulk, president of Above and Below H20, in Sacramento. Faulk used to dive in the tanks himself to look for corrosion and disrepair, but now he uses an 8-pound swimming robot instead. From outside the tank, Faulk inspects the water tanks without risk of human contamination or unsafe conditions.

Dotting the US landscape are 400,000 steel and concrete water storage tanks. Every year, 80,000 tank inspections come due, using the recommendations of the AWWA (American Water Works Association) for an inspection every five years. In many towns, inspections are dreaded and put off for lack of funding for human divers.

Sending divers into drinking water tanks has long been the practice for inspecting the structures. But it is dangerous and can pose health risks. Now, more town and city engineers are looking into the use of the VideoRay ROVs (remotely operated vehicles) to co-exist with divers and make tank inspections safer, more affordable, and more frequent.

Man versus machine
In a diver-led inspection, the diver lumbers up the steps of the tower in heavy sterile suit. He carries pounds of instrumentation and camera equipment. There are many areas of the tank that are too small for the diver to enter and inspect. If his equipment fails, he could drown in the tank and risk contamination of the drinking water.

By contrast, with the VideoRay ROV inspection, Faulk immerses the 8-pound sub in disinfectant. He then climbs the ladder toting the sub with its light tether in tow. By hand, he lowers the submersible in the 2x2 foot or smaller hatch. Once inside, the VideoRay can get into tight spots divers can’t.

The VideoRay sub completes survey of seams, cables, and pipelines. Faulk records his mission through the VideoRay’s camera eye on videotape and DVD for review by engineers. During the mission, no one got wet.

From underwater weddings to drinking water
In 1995, Faulk focused Above and Below H20 on potable water inspections. In February 2002, Faulk purchased the VideoRay ROV and has seen his business flourish. He says that people who manage the water tanks are buying into the VideoRay as an alternate to divers, because immersing humans into drinking water is more expensive and poses safety and health risks.

Faulk says he likes the VideoRay primarily because it is small enough to fit in the trunk of his car. Beyond the safety value, VideoRay is easier to pack and transport than a trailer of divers and gear. According to Faulk, the VideoRay is “one of the most lucrative tools I have ever used.”

The VideoRay uses 300 watts of power from a car battery with inverter, small gasoline generator, or any household outlet. The current running through the tether to the submersible is a safe 48 VDC, so the sub can be handled in the water. It runs from a small generator, a car battery, or a standard wall socket. The control box includes a joystick similar to those on video games. A few knobs control the 20-watt halogen lights and tilting and focusing the high-resolution camera.

Since his purchase of the VideoRay, Faulk has changed his business emphasis to ROV contracting, with diving as a support branch. He explains that the competition in diving inspections was so intense. Now, he can bid the ROV at a lower price than would be possible with divers and get more volume. His calendar is filling up.

[ Above and Below H20 is located at 2325 25th Avenue, Sacramento, CA 95822-2212.]

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Related articles:

• VideoRay Explores Guanting Reservoir in China
• In Commercial Diver International's November 2004 issue, "Micro-ROVs Overcome Diver Safety Concerns."
• "Alert Diver" Magazine Highlights Role of ROVs in Hazardous Environments
• "Mini-subs handle underwater chores", in Engineer Update, published by the US Army Corps of Engineers.
• 8-Pound Swimming Sub Makes Diver-less Water Tank Inspections a Reality

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Suggested Configurations

For less demanding water tank inspections, we recommend the VideoRay Explorer. For more intensive operations, we recommend the VideoRay Pro III with:

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