This week, the last samples of the year are collected from the region's treatment plant.
Similar surveys are being conducted in more and more other municipalities around the country.
Of the 50s that examined their wastewater in 2019, Mjölby stood out as the municipality with the most amphetamine in the water.
"You get scared" Mjölby politician about amphetamine abuse in the municipality.
Amphetamine in the west, cannabis in the east
Motala has also had a lot of amphetamine in its measurements, while cannabis seems to dominate in the eastern part of the region.
In Åtvidaberg and especially Valdemarsvik, the amount of cannabis has increased by several hundred percent in recent years.
Read more about the cannabis problem in Valdemarsvik here.
The Bråvalla festival was also investigated
In Norrköping and Linköping, the use of cannabis, amphetamine, cocaine and tramadol seems to have decreased in the past year.
Petra Isaksson is the coordinator for crime and drug prevention in Östergötland.
she says that they also did tests on the wastewater during the Bråvalla Festival a few years ago, but that they did not show any sharp increase in drug traces.
See the feature in the player above on how the measurements are done.
This is how much drugs are used in your municipality:
Here is a table from the County Administrative Board's latest report on drug traces in the wastewater in Östergötland.
The figures are averages from three samples taken at the same time in the region's municipalities:
Photo: Östergötland County Administrative Board