Task

A city in Holland needed to sample rainwater in the sewer during heavy rainfall. After longer dry periods, heavy rainfall can wash considerable amounts of pollution from surfaces such as roofs and roads into the sewer. The local authority wanted to determine this particular load and was therefore looking for a sampling device that could fulfil these requirements.

The desired device had to be lightweight and easy to install in the sewer. It had to be able to take around 2 litres of samples at an adjustable height in the sewer. It also had to be explosion-proof, energy-efficient with a standby time of up to 3 months and cost-effective.

Impossible! Was our initial assessment. But our technical ambition finally led to a solution.

Our solution

We developed a device running entirely without energy. An evacuated container with an inlet valve opening on water contact.

Function

The device is installed in the duct in such a way that the inlet valve is positioned exactly at the desired height to trigger sampling. This arrangement allows the device to remain on standby for months without impairing its function.