The peatlands constitute a water reservoir preserving clean water. Peat acts as a filter for the purification of contaminated precipitations, which during high water periods flow into the groundwater through sandy soil and limestone cracks in the mire border regions. Draining of mires feeding from groundwater changes the intragroundwater flow into the overground one. The acid water, directed into rivers, endangers the local biota. Particularly significant are peatlands as water reservoirs in the mining-industrial regions and in the surroundings of big towns.
According to nature conditions, the exhausted peat areas should be reconstructed into water reservoirs, natural or cultivated berry patches.
The bogs of Estonia are probably one of the most researched wetlands in the world. At present our bogs have been extensively mapped and the peat resources determined.