In the Tarnava river basin two long intervals of drought were registered, the first one between 1945 and 1951, while the second one was between 1983 and 1994 (Gajtescu and Zavoianu, 1998). As compared to the previous period, the 1983—1994 droughts present a few particularities, being longer in time, but in the same way less homogenous than the previous ones. The discontinuities of recorded values were noticed in 1985—1988. A major negative influence of water users on the flow in Tarnava basin was noticed in 1986, 1987, and 1990 when the discharges decreased below the multiannual average values, restrictions were not imposed for the storing water and the perennial storage reservoirs to compensate the discharges that did not exist. The drought phenomena must be monitored with great attention, by better control of water users to decrease the risk of pollution, reactivate own sources of water supply so as to reduce discharges consumed from centralized sources. Because of its extensive duration, intensity and effects, the drought in 2000 can be considered one of the most powerful in our country in the 20th century. On the whole territory of the country the rainfall decreased by 33.4% of the usual quantities. In 2000, on small surface creeks in the Tarnava basin, the annual flow was lower than the multiannual, some even became dry on the whole river course. For example, The storage reservoirs in the basin played an important part in supplementing the discharges in drought periods thus meeting the water users' needs. In the Tarnava hydrologic basin, in 2003, the discharges decreased below the monthly average yet without reaching the warning threshold. On the main river courses in the basin there were not significant discharge drops to the densely forested areas in the upper basin where the tributaries have an even flow and also to the permanent storage reservoirs, such as Zetea on the Tarnava Mare river and Bezid on the Tarnava Mica river, which compensate for the little deficit on these water courses.
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