Hibbard Inshore services

Long tunnels are often an integral part of many large hydroelectric dams and aqueduct systems. They present difficult challenges for inspection and maintenance due to their limited access, long penetrations, and typically large diameters. Hibbard Inshore is a world leader in the inspection of fully flooded long tunnels. Eliminating hydrostatic tunnel pressure through dewatering can increase structural stress and the likelihood of failure. In addition, dewatering typically causes increased outage times. Hibbard Inshore eliminates these problems by offering its clients ROV based alternatives. Hibbard Inshore works directly with its customers to design project-specific inspection methods with a focus on reducing the total cost of inspection by minimizing outage times, performing inspections in flow to allow continued generation, and limiting structural and safety risks.

Underwater structural inspections for dams are critical to identify any signs of degradation or loss of functionality. With more than 29 years of experience, Hibbard Inshore’s inspections have included penstocks, face of dam, lower outlets, toe of dam, intakes, head gates and seals, trash racks, turbines, and turbine shut off valves. Hibbard Inshore can equip each of their ROVs with cameras, lighting, multiple types of sonar, and additional non-destructive testing sensors such as ultrasonic thickness gauges in order to provide the best possible look at each underwater portion of a dam. Often, because Hibbard Inshore is able to use these various technologies, inspections can be performed in less time than inspections requiring video only reducing outage times and time onsite.

Internal inspections of water and sewer lines are a primary service offered by Hibbard Inshore. Hibbard Inshore’s ROV fleet has the ability to travel extensive lengths through filled, partially filled, and dry pipes to collect data and determine the condition of these pipes using swimming floating and crawling vehicles respectively. By operating all three types of vehicles for all three situations, Hibbard Inshore can perform inspections regardless of conditions, giving their clients the ability to select a single provider for all their sewer inspection needs. When it comes to potable water inspections, Hibbard Inshore has electrical vehicles that are used just for those inspections in order to follow all rules and regulations and to reduce any risk of spills or contamination.

Hibbard Inshore understands that dredging and debris removal in low visibility or deep water can be challenging and at times, unsafe for commercial dive teams. Often, there are buildups of debris or sediment in places such as power plant intake tunnels, pump intakes or rock traps that need to be cleaned but are confined in nature. Through the use of ROVs, specialized pumping equipment and multiple forms of sonar, Hibbard Inshore is able to monitor and control the dredging, jetting, and debris removal processes in some of the most difficult areas. Often times, the vehicles and methods used by Hibbard Inshore will allow adjacent generating units or pumps to remain in service while only the unit where the Hibbard team is actively cleaning will require outage.

Rather than produce a quantitative set of bottom elevations, sidescan sonar surveys generate a qualitative suite of underwater imagery. For projects where a snapshot “picture” of the bottom is necessary, sidescan sonar surveys can be an excellent choice to identify bottom features such as submerged debris, remnant derelict infrastructure, exposed bottom geology, hazards to navigation, and shipwrecks. Sidescan sonar surveys can also be used to monitor ongoing progress for sensitive underwater construction projects such as protective mattress, rip-rap, and structural placement.