Georgia is rich with water resources. There are 26060 rivers and their total length is about 59 thousand kilometers. In the hydro-geographical network the important part (99%) makes the small rivers (length - less than 25 km).
There are a lot of thermal and mineral water springs in the country. There are many natural and mechanic water reservoirs. Important supplies of ground water are in limestone horizons on the territory of Caucasus.
Water resources are distributed unequally and they are mainly in the west part of the country. Georgian rivers are distributed into two main basins and they are divided by Likhi ridge. There are about 18109 rivers are in the Black Sea basin. This is 70% of total rivers. There are 7951 rivers (30%) in the Caspian Sea basin. 555 rivers of the Black Sea basin and 528 rivers of the Caspian Sea basin are studied hydrologically.
Nearly all rivers of East Georgia make the whole system and flows down into the Caspian Sea and West Georgian rivers join the Black Sea independently. The biggest river of Georgia is Mtkvari. Only its middle part (400 kilometer) is on the territory of Georgia. It begins in Turkey and flows down in the Caspian Sea on the territory of Azerbaijan. The largest river in West Georgia is Rioni. It covers only the territory of Georgia. It begins in Great Caucasus Mountains goes through Kutaisi and Poti into the Black Sea.
There are about 860 lakes in Georgia. Most of them are very small so their water surface area is about 170 km2. (It consists of 0.24% of territory if the country). Most of them are fresh waters. Paraoni Lake has the largest area in Georgia. Tabatskuri Lake is the biggest one with its volume and Ritsa is the deepest lake not only in Georgia but in South Caucasus too.
In Georgia wetlands cover 225 thousand ha on Kolkheti Lowlands.
West Georgia is bordered by the Black Sea and its coastal zone along Georgian border is 315 kilometer.
43 reservoirs serve to hydroelectric stations and irrigation system. 35 ones among them are in East Georgia. Water reservoirs are very important in economics of Georgia. Nowadays in Georgia more than 75% of electric energy is generated in hydroelectric stations. Irrigation system has vital importance for agriculture in the East Georgia that is drier part of the country.
Natural supply of fresh ground water of the country is about 18000 million cubic meters. The whole prognosticate and exploitation supplies are about 10600 million cubic meters.
There are a lot of ground water storage, especially on the lower slope of Great Caucasus and on the plateau of Akhalkalaki and Marneuli. The total debit of these springs is 340 m3 in a second. In total water supply systems provide 600 million cubic meter drinking water a year. 90% of this drinking water is based on ground water and they do not need any special generation besides chlorination.
Now water resource management is on the base of administrative principles in Georgia. It is less effective following the nature of water and reality that ‘water does not know any borders'. Administrative model cannot provide planning effective usage of water resources within river basin on the bases of interests of water beneficiaries and also considering environmental purposes.
Georgian rivers are mainly polluted with nitrogen or sometimes with heavy metals (River Mashavera, Bolnisi Region; River Kvirila, near Chiatura and Zestafoni) and rivers of the Black Sea in Adjara Regions are polluted with oil products.
The main sources of polluting surface waters in Georgia are water supply and sewerage system, heat power engineering and industry.
Water pollutants according to the sectors are distributed as follows:
- Water supply and sewerage system - 344,1 million cubic meter a year. (67%)
- Heat power engineering - 163,8 million cubic meter a year. (31%)
- Industry - 9,6 million cubic meter a year. (2%)
So the main pollutant for surface waters is communal sector (sewerage of towns and populated areas). Now none of the water cleaning structures can provide cleaning according to project quality. Biological cleaning of water is not available in any towns. Primary mechanic cleaning is implemented only on Tbilisi-Rustavi regional cleaning structure. As a result, there is important pollution on water objects.