The city of St. Peterburg, in the Tampa Bay Area, on Florida’s west coast, is considering using robots to inspect sewage pipes. A $600,000 contract with RedZone Robotics would provide autonomous crawling robots that help detect leaks faster than conventional methods, so they can be repaired, reports the Tampa Bay Times.
The St. Petersburg sewage system has been experiencing problems for years now. In 2015-2016, heavy rainfall associated with Tropical Storm Colin and Hurricane Hermine led to massive sewage discharges into Tampa Bay, leading to beach closures. A 2016 study found that ageing, leaky pipes were one of the major factors leading to system failure. On a dry day, up to two thirds of the city’s sewage flow consists of groundwater that enters the leaky sewer system; when it rains, the system is overloaded.
The St. Petersburg sewage system has been experiencing problems for years now
A 2017 report by the Florida Fish and Wildlife Commission blamed two decades of sanitation system neglect by the city’s administrations for some of the largest wastewater discharges in the history of Florida. Poor decisions included the closure of the Albert Whitted water reclamation plant in 2015, without upgrading the capacity of the city’s other three wastewater treatment plants. An agreement between to city and the state pledged to invest $326 million to overhaul the sanitation system.
The city has to assess some 4.7 million feet (more than 1,400 kilometres) of sewer pipeline in five years, and that is where robots can help. Together with conventional, slower methods, city officials estimate the work could be done within that timeframe. In the past, the city used CCTV trucks which use video cameras introduced from one manhole to the next to inspect the pipes; with that system, staff has to watch the video footage to identify areas that need fixing. The trucks can check some 2,000 feet (600 metres) of pipe every day, while the robots can check up to five times that amount (3 kilometres) every day.
The robots use video cameras, sonar and radar technology, and score the pipes on a scale of 1 to 5, indicating if they are cracked, displaced, or could be missing pieces. They would be used in the areas of the sewerage network that have most problems. A map of the pipe network is then created to prioritise the areas that need work.