Via Magnus Lidberg, Mölndal has purchased sensors from AXsensor to use for detection
inflow and infiltration in their waste water lines. By looking at level changes in the waste water lines
and correlating it with rain data, this method can provide a quick overview of where to focus your efforts
to reduce the amount of inflow and infiltration.
In addition to identifying inflow and infiltration in the waste water pipes, Mölndal also wanted to see how a
part of the pipeline network worked in connection with rainfall. Multiple AXsensor sensors
were placed serially along a stretch that Mölndal was particularly curious about.
During the Christmas holidays, Magnus discovered that there were very high levels in some of the wells there
the measurement was taking place. In a well that was connected to a 400mm pipe the levels were as high as
1300–1400 mm!
Image of graphs taken from AXsensor’s portal in order to illustrate the collected data. It was in this system that Magnus discovered the high water levels and was eventually able to find the cause of the problem.
These levels made Magnus suspicious and it was time to investigate further. Together
with the oprational staff Magnus checked that the pumping station downstream of the well was working and
concluded that it worked without any problems.
After a systemic check through the wells they where
finally able to discover the root of the problem! Roots where
stuck in the well before the pumping station. The pipe line there
is an 800mm line and it was almost completely overgrown
with massive roots that severely limited the flow.
“If we didn’t have AXsensor’s level sensor in place, we would
not be able to detect this before a complete stop and likely
a flooding would have occurred”
– Magnus Lidberg, wastewater engineer at Mölndal stad
Since the discovery, Mölndal has fixed the problems and the pipe line is now working as designed.
The work with inflow and infiltration detection using AXsensor equipment is now continuing on a new part of the pipeline network.
Magnus Lidberg is a wastewater engineer in the city of Mölndal and is responsible for
the measurement project with the sensors from AXsensor. Magnus has previously worked
in in both municipalities of Gothenburg and Kungälv . Last employer before
Mölndal city was Tyréns where he worked as a wastewater investigator. Magnus has
over a decade of experience in investigations and inflow and infiltration work.