ST. PETERSBURG — Here come the robots.
Autonomous crawling robots may soon be in sewage pipes under the streets to help fix the city's wastewater woes.
The robots would allow the city to scan for pipe problems three to four times faster than underground video cameras, allowing it to make repairs more quickly, said the senior water resources manager Lisa Rhea.
The City Council is mulling signing a $600,000 contract with RedZone Robotics to provide its "Solo" autonomous crawling robots for the Water Resources Department. The final contract should go before the council in August, said RedZone Robotics sales operations manager John DePasquale.
In 2015-16, the city's antiquated, overwhelmed wastewater system overflowed by up to 1 billion gallons. Part of the problem was old, leaky pipes. In 2016, a consultant told the council that on a dry day about two-thirds of the sewage flow was due to groundwater seeping into the old pipes. When it rained, the pipes were overwhelmed. That played a big factor in those storm-fueled sewage discharges.
The robots will help the city spot leaks more quickly, Rhea said, so they can be repaired faster.
The devices score pipes on a scale of 1 to 5 that indicates whether they're cracked, displaced or even missing pieces. They'll also create holistic maps of the pipe system and help prioritize what sections of the pipe network need the most work.
"Now, you have a peace of mind and don't have to react anymore," DePasquale said.
THE INVESTIGATION: Rick Kriseman's administration lashed in St. Pete sewage report
The Florida Fish and Wildlife Conservation Commission's 2017 report into the city's sewage issues said Mayor Rick Kriseman's administration made poor decisions before and during the crisis, including shutting down the Albert Whitted treatment plant months before the first discharges in 2015. The report also said past administrations set the stage for the crisis by under-funding the sewage system.
After the report was issued, the Florida Department of Environmental Protection reached a consent decree with the city that required it to spend $326 million spent to fix and upgrade the system. Sewer problems have persisted since then, and the city was found to have violated the order in 2017.
The decree required the city to evaluate about 4.7 million linear feet of gravity sewer pipe in five years, records show. That's where the robots come in.
The autonomous devices would be paired with traditional, slower methods to help meet that requirement, Rhea said. If the first full run-through is successful, she said, it could take less than five years to finish that evaluation. The robots will be used to inspect the worst, leakiest pipes in the city.
The current contract is just for nine months. But if the robots do a good enough job, Rhea said they could be used more extensively in the future.
Historically, the city has used CCTV trucks, which use video to inspect pipes. The trucks would run video cameras through sewer lines from one manhole to another to identify cracks. After recording all that pipeage, Rhea said, workers would then have to go back and watch the video to identify areas that needed work.
Those trucks can inspect about 2,000 feet of pipe per day. RedZone says its robots can scan 7,000 to 10,000 linear feet of pipe per day.
Workers program the robots where to go and insert them into manholes. Then Rhea said the devices scan the pipes using video cameras, sonar and radar to get a "more definitive" examination of the system. Then the city could produce a map and highlight the problem areas.
"You can take a step back and...say 'Wow, this neighborhood has a lot of problems, although they're not all the worst problems, since there's a concentration it would be worth it...to focus on this neighborhood's repairs,'" Rhea said.
More than a dozen municipalities in Florida have used RedZone sewer robots, DePasquale said, including Oldsmar and Palm Bay.
Winter Garden used RedZone's "absolutely phenomenal" robots this year, said assistant city manager of public services Jon Williams. The city plans to use the robots again in the next fiscal year, he said, because they "drastically" cut down inspection time.
"It has made a huge difference," Williams said.
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