The Osterholz cemetery was completed in three stages. The oldest part in the south was created in 1920, the second area followed in 1956 in the north. In 1968, the last extension (northern tip) was carried out. An extensive network of canals stretches all over the cemetery – ponds are integrated especially in the more recent areas. In addition, there are two chapel ponds in the cemetery, from which the irrigation water is drawn. The canal systems on the Osterholz cemetery grounds are characterized by gradual siltation. This siltation is caused by the input of organic material, such as leaves and branches from the surrounding trees. Over the years, this creates a continuously growing sediment layer with a high organic content.
A comprehensive survey of the condition of the water body in 1998 has provided a basis to improve the general condition of the water body in the Osterholz Cemetery with targeted rehabilitation and restoration measures. In addition to many small measures, such as a targeted nutrient removal through a plant mowing and a local fish stocking; a soil filter system was also installed, which treats the turbid water from the river Wümme before it is fed into the system as filling water.
