Maunula sand filtration solution

Maunulanpuiston hulevesien hiekkasuodatusratkaisu.
Kuva: Eeva Eitsi.

The Maunulanpuisto stormwater sand filtration solution was implemented in 2015. Its catchment area is approximately 15 hectares and its location can be seen on the map below. The solution purifies the stormwaters of northern Pasila before they are discharged into Haaganpuro.​

The filtration area is able to process and clean normal rainfall. In connection with a heavy rain event, part of the water passes next to the solution in an overflowing ditch, which drains the water into another small settling basin before the brook.​

The cleaning performance of the solution has been studied and it removes oils, phosphorus and heavy metals from the water well.

Photo: Eeva Eitsi.

The catchment area and structure of the sand filtration solution

  1. Rain and meltwater collection area​
  2. The water is led from under the Metsäläntie road via a sewer pipe to the discharging basin ​
  3. Settling basin for solid matter ​
  4. Biofiltration area: Water is delayed in the top layer of the filter, where the wetland vegetation binds nutrients and heavy metals. Water is further filtered into sand deposits where nutrients and contaminants are removed by microbiological processes​
  5. The purified water is directed through the well and sewer pipe to Haaganpuro