Engineers across the country have put drones to good use for public projects, making it much easier and faster to spot problems. In Minneapolis, drones will be used to check for sewer problems from the sky. The new development is to be applied for smoke testing in sewers across neighborhoods in Minneapolis.

A First for the City

In Minnesota, drones have been in use since 2015, inspecting bridges and ditches. The technology will be introduced in Minneapolis with this maiden expedition. Crews from the public works department will have an easy time finding problems with sewers as the drones can spot faults much more efficiently from above the ground. While it may take some investment to keep the new developments alive, the city can gain a lot from the project, making it worth the trouble.

This year, smoke testing will prioritize areas in the Northeast and Southeast in parts of the central Minneapolis riverfront. Residents in the area have already received letters informing them of the operation so that they are not alarmed by a drone flying over their streets and taking photos. According to Katrina Kessler, director of Surface Water and Sewers for the city, the drones will not be flying over private property or people’s homes. The statement was made to assure residents that the drone project is purely for the improvement of service delivery in the public works sector and that there are no covert motives behind it.

Drone to Help Stop Sewage Spills

Smoke testing is important in determining whether there are connections between the city’s sewer systems, the sanitary and storm water sewers. The city has gone through a lot of trouble trying to separate the two sewer systems, which prevents sewage spills when large rains fall. For a long time now, the Minneapolis area has been immersed in efforts to separate the two, and after a decade, 99% of the systems are now separated. So far, experts have gone through three quarters of the sewer system and are almost done testing leftover connections. Smoke testing is one of the most efficient ways of finding connections that may otherwise be difficult to spot.

The testing is done by pumping non-toxic smoke into the sanitary sewers and watching where it emerges from rooftops. The smoke should come out of the sanitary exhaust vents but if it comes up from curbside storm sewers, then that’s a red flag

The endeavor should not be difficult when dealing with normal residential blocks. However, it gets a little trickier in industrialized areas where you have large apartments with flat roofs. This would mean that crews would have to go to the top of every roof for successful inspections, which takes a lot of time and a sophisticated level of co-ordination. Besides, going up to every roof can be a health hazard as some of the areas are hostile to human occupancy.

Drones will solve the problem in a simple and easy way
The use of drones will allow crews to examine rooftops from the photos they take. The city reckons it is much simpler to have a drone show photographs of the area than have people manning the vents to check for smoke.