Up until the late 1990s, high-level liquid manure tanks made of high-pressure impregnated wooden planks were very popular. As long as the tank is full, the wood swells and thus provides a reliable seal. The anaerobic bacteria in the liquid manure are not able to decompose the lignin in the wood, which means that it can last well over 50 years.
The planks are held together by steel strips, which were mostly galvanized from the 1980s. These liquid manure silos were manufactured, for example, by Eisele in southern Germany and Vogelsang in northern Germany. Even today, manure silos made of wood are still in use in many places, provided that the steel belts and wooden planks are in good condition, they are still protected, only for new buildings wood is no longer an approved material.
These tanks are a cost-effective option for storing manure, but one disadvantage compared to modern systems is the old manure pump, which only delivers around 8000 liters per minute.

Wooden Liquid Manure Tank:
Price: 15000 $
Daily Upkeep: 20 $
Capacity: 650 m³
Diameter: 12 m

Wooden Liquid Manure Tank Extension:
Price: 11000 $
Daily Upkeep: 14 $
Capacity: 650 m³
Diameter: 12 m