Vízügyi Közlemények, 1997 (79. évfolyam)

2. füzet - Fejes Béla: A Mura vízgyűjtőjén fekvő települések vízellátási, csatornázási és szennyvíztisztítási helyzete

A Mura vízgyűjtőjén fekvő települések vízellátási, csatornázási és szennyvíztisztítási helyzete 205 Water supply, sewerage and sewage treatment situation of settlements of the drainage basin of the River Mura by Béla FEJES Sanitary Engineer Zala County of Hungary falls into the drainage basins of two rivers, the River Zala and the Rivez- Mura. The catchment area of the River Mura is 1,994 km

2. In the Mura Basin there are three larger towns (Nagykanizsa, Letenye and Lenti) and 137 villages. The settlement structure of the basin is characterized by small villages. As a consequence of this situatian there are 24 smaller and larger regional waterworks supplying 117 settlements, while the number of single-town waterworks is 23. Public water utility agencies of the Mura basin include: ZALAVÍZ Pic of Zalaegerszeg, the Southern Zala Water-supply, Sewerage and Bath Works of Nagykanizsa, the HIDRO GM of Zalaegerszeg, the MULTILINE Ltd of Kaposvár, the local engineering unit of DRV Pic at Kaposvár and the VASVÍZ Pic. af Szombathely. Nearly 99% of the population receives piped water supply, while the ratio of the number of homes connected to the network to the total is somewhat worse. Water consumption of the population has been substantially decreasing in the period 19901995 both in the cities and the villages (Table /.). The main reason of the decreasing water consumption is the repeated (annual) and substantial rising of the price of water. As a consequence of this situation several consumers have returned to the use of dug wells and the water supply for watering animals and irrigation is also being increasingly based on these free-of-charge sources of water (Table II.). Due to the decreasing of water consumption flows of the network became sluggish and water is being stored in the reservoirs for much longer time than before. This situation deteriorates the quality of water, frequently turning it non potable. On the quantitative side the water supply development can be considered as a completed process. Complex water treatment is being increasingly needed at many waterworks (Table III.). Settlements of the Mura river basin fall into the quality class VI. of the relevant regulations of the National Water Authority. Sewerage and sewage treatment facilities of the three towns can be considered completed ones. Each of the three sewage treatment plants has free capacity and thus they can receive the sewage water of neighbouring settlements. Sewage quantities generated in the period 1

990-1995 in the three towns are given in Table IV. 22 settlements of the Mura basin have sewerage and sewage treatment and these refers to the complete sewerage of the towns. Nevertheless the ratio of homes connected to the system shows a less complete picture. There is a wide range of the type of facilities used for sewage treatment. The treatment efficiency of the plants is generally acceptable. Sewage quantities generated in the villages are shown in Table VI., for the period 1990-1995. On the basis of the operation of the sewage treatment plants of the villages the following conclusions can be drawn: — Sewage flows of rainy periods are much (2-3 times) higher than the dry weather flows, indicating that the separated sewers receive stormwater discharges as well. — Water quality investigations revealed very high COD values of the inflowing sewage water. This indicates the connection of dischargers other than communal ones (presumably liquid manure) to the sewer system. Target oriented financial support of sewerage (since 1991) gave an impetus to the development process in the villages. Nevertheless substantial financial resources of both the local authorities and the citizens are needed for such investments, in addition to the government subsidy.