Groundwater and spring water from the Vogelsberg, along with water from the dem Spessart hills and Hessian Ried provides drinking water for the Rhine-Main region. As early as 1876 were springs in the eastern Vogelsberg enclosed for that purpose and the construction of water pipes from the Spessart and the Vogelsberg to the city of Frankfurt. A lack of understanding of the particular hydrogeological and ecological situation in the Vogelsberg and excessive withdrawal resulted in springs drying up, cracks appearing in buildings and subsidence of the ground. The Upper Hessian Water Companies (Oberhessischen Versorgungsbetriebe AG, OVAG) are the largest water suppliers in the Vogelsberg: they pump out around 30 million cubic metres of ground water annually from their wells; about 2/3 goes to the city of Frankfurt in the Rhine-Main region.