Cistern

A cistern (Latin cisterna - underground water tank ) is an underground or covered container for drinking or industrial water.

Area of ​​application

In areas with irregular rainfall and hard to reach groundwater resources cisterns are used as buffer tank for water storage systems for home or small towns. They are used to store the supplied initiated precipitation or surface water. In areas with dry periods and rocky ground depend on them for the entire water supply, so that a civilization without the cistern would not have been possible.

Traditions with cisterns, there are for example:

• In the Levant
• In Istanbul and Rome
• On the island of Pantelleria
• In the Balearic Islands
• At the North American Acoma Pueblo Indians

Far more common than drinking water are Nutzwasserzisternen today. They are also sometimes referred to as retention basins. In the year 2002 there were in Germany about 24,000 stormwater retention basins in operation. In the water-rich Central Europe cistern water is in a private house area is increasingly used as process water for washing machines, toilets and garden irrigation, as no preparation necessary for this purpose and the quality is sufficient. In case of inadequate public water supply cisterns can also serve as a clear water reservoir.

In the Mediterranean area cisterns are applied for over 7000 years. They are often assembled from large stone blocks and with a capstone, or a ceiling construction to avoid contamination. Reaching the changing water level is ensured by a staircase or by suitable lifting equipment.

The historic building materials for cisterns are masonry or concrete. If possible, you have beaten the cisterns in the bedrock. Today, complete, finished container (2-40 m³ ) of plastic or concrete are available. They are used almost solely for the use of rainwater.

Partially abandoned septic tanks cleaned or cleaned oil tanks are used as a cistern for watering the garden.

Water quality

Rain water is problematic for drinking water: In general, the passes with bird droppings, leaves, dust and other contaminants water mixed without or with a low pretreatment in the cistern. Because of the potential bacterial load must be at least disinfected thoroughly (eg by boiling ) before it is suitable for drinking.

Even when used as process water to be reckoned with odor problems, because organic substances can pass into the cistern to rot.

Historical

Cisterns have been used in the Stone and Bronze Ages. In the Middle Ages is often found in castles on hills where you could not dig so deep wells. It is important to distinguish between the tank and filter tanks cisterns. A filter cistern was built eg on the Rieger castle in Styria, where a cistern was slapped on the lava rocks. The rainwater was collected by sand filter in the tank. By filter the rain water was purified and enriched with minerals.

Famous cisterns

One of the most impressive cisterns is Basilica Cistern in Istanbul ( filming location for the James Bond film From Russia with Love ). In addition to this is the highest point of the old city of Caceres carved into the rock cistern, called aljibe of Caceres, the largest in the world. In 1986 this place was in the Spanish Extremadura the status of UNESCO World Heritage Sites. Another well preserved aljibe is Mérida.

The Arabic word " _ibb " for cistern was " aljibe " adopted as into Spanish. Its importance has preserved it to this day. Despite competition from the Latin " cisterna " the word is so vital that it has been transferred to modern concepts such as " camión aljibe " " tank car". From the Reconquista, as one warlike grappled with the Moors, the word had another meaning, namely " dungeon ", " prison ". This is because that one has the prisoners locked in their thousands in underground vaulted tank, as you can still visit impressive in Morocco Meknes today. With the end of hostilities, these word meaning disappeared. The Uzbek form of the cistern is the Sardoba, but which can be fed by rivers. Impressive is Malik Sardoba between Samarkand and Bukhara. On the island of Pantelleria, some Punic cisterns still serve as water reservoirs. They are connected by an overflow system complicated and have a long- oval form, as it is known from punic branches.