Stormwater

Stormwater is rainwater and meltwater that flows off the surface of the earth, the roofs of buildings and other built surfaces.

The goal of stormwater management is to promote the absorption of stormwater at the place of its origin and to prevent harm caused by stormwater, e.g. floods, moisture damage to buildings or the weakening effects of harmful substances contained in stormwater on the quality of drainage systems and groundwater. As climate change and extreme weather events become more common, the importance of stormwater management is emphasized.

The Water Supply Authority takes care of the stormwater drainage (pipe sections) of the urbanized areas in the stormwater drainage area agreed with the municipality. The municipality is responsible for open ditches, pools and other organization of stormwater management in the site plan areas. So far, no separate stormwater fees are charged in Hollola.

The owner or occupier of the property is responsible for the stormwater management of their own property. Stormwater should primarily be absorbed into the ground on your own property. If, for example, the soil conditions of the plot prevent absorption, stormwater should be delayed on the plot for as long as possible before, for example, leading to a ditch or a storm water drain. The municipality's building order and possibly also the site plan may contain regulations regarding stormwater.

Stormwater may not be directed onto someone else's property, driveway, bike path, sidewalk, or street without the landowner's permission. Instructions for residents and property owners on preparing for stormwater floods can be found in the links.

It is prohibited to lead storm water and drainage water from foundations into the waste water drain.

Since stormwater is not cleaned, each of us must do our part to ensure that garbage, oil or other harmful substances do not enter the environment through stormwater. If necessary, dirty storm water should only be led from the property after the sand and oil separation well to the municipal storm water system. Stormwater should primarily be directed to the municipality's stormwater system consisting of open ditches, depressions, wetlands and similar structures, and secondarily to the water supply plant's stormwater drain. 

Stormwater is also an opportunity to diversify the yard and park environment.

Rainwater can be used in the yard in many ways, e.g. by collecting it for irrigation, building beautiful rain gardens, delay or water basins and stone streams. Yard areas can also be realized with permeable pavements.

More information and good ideas about stormwater management in the yard can be found in the video below.

The comprehensive stormwater management plan for the entire municipality of Hollola was completed at the beginning of 2022. The general plan-level plan presents and examines the stormwater management solutions and structures that are part of the municipality's stormwater system, as well as their catchment areas and discharge locations. When preparing the plan, municipal residents and stakeholders were also involved, e.g. with a survey about the successes, needs and risk areas of stormwater management.