Problems of use underground water in Lithuanian water supply systems

Abstract

In Lithuania drinking water is prepared only from underground sources. For these purposes 115 watering-places which include 1300 wells are equiped. About 940 thousand cubic meters of drinking water are supplied to consumers every day. A total lenght of water supplying network is more than 3610 km. That includes 20% steel pipes, 78,5% pipes from cast iron and 1,5% pipes from other materials. About 30% of network are in exploatation more than 25 years. Till now drinking water quality is regulated in accordance to standart GOST 2874-82. 58% of obtained underground water does not correspond to this standart but only 61% of this mount is treated before supplying to the network. The quality of drinking water is influenced by the condition of network’s pipes, inner walls of which aren't protected from corrosion. Because of the bad quality of drinking water about 71 percent of consumers are complaining. Some other problems must be mentioned: 1) low coeficient of energy use in water supply pumping stations; 2) lack of attention to equipment with low energy demands, to rational relationships between different units of water supply system, to water metering and optimisation of systems' management; 3) Water supply management practise does not correspond to the market economy; 4)the Soviet rules and norms for designing and construction of the water supply facilities, which are in use till now, do not correspond to local conditions; 5)the largest Lithuanian cities haven’t got long-term plans for developement of their water supply systems.