Groundwater protection

The goal of groundwater protection is to maintain the quality and quantitative status of groundwater at a good level.

Classification of groundwater areas

A groundwater area is a geologically outlined soil formation or bedrock zone that enables significant groundwater flow or water abstraction. In Finland, groundwater areas are classified into classes 1, 2, and E. The classification criteria are based on the groundwater area’s suitability for water supply purposes and its protection requirements:

Class 1 includes groundwater areas important for water supply, where water is used or intended to be used for municipal water supply or as household water in quantities exceeding an average of 10 cubic meters per day or for the needs of more than 50 people.
Class 2 includes other groundwater areas suitable for water supply use that, based on their groundwater yield and other characteristics, are suitable for the use referred to in point 1.
Class E includes groundwater areas on which a surface water or terrestrial ecosystem is directly dependent.

The outlines and classifications of groundwater areas in Hämeenlinna and Hattula were reviewed between 2016 and 2023. Hämeenlinna has a total of 58 groundwater areas (with Hämeenlinna as the primary municipality), of which 19 are Class 1 groundwater areas important for water supply, and five are Class 1E groundwater areas. There are 33 Class 2 groundwater areas suitable for water supply, and one Class 2E groundwater area. Hattula has a total of 9 groundwater areas, with three being Class 1, five Class 2, and one Class 2E groundwater area.

Explore Hämeenlinna and Hattula groundwater areas in Paikkatietoikkuna (in Finnish)