Water-power system "Yovkovtsi"

The Yovkovtsi Reservoir is built for drinking - water supply of the towns – Veliko Tarnovo, Gorna Oryahovitsa, Lyaskovets, Elena, Zlataritsa, Debelets, Kilifarevo, Polski Trambesh, and Dryanovo – and other settlements in the region. Water-power system includes the dam "Yovkovtsi", water-supply non-pressure derivation, DWTP "Yovkovtsi", siphon "Pchelishte" and water-conduits for Veliko Tarnovo, Gorna Oryahovitsa, Dryanovo, Stazhitsa, Zlataritsa and other settlements in the region.

Dam "Yovkovtsi"
The dam "Yovkovtsi" is built on the Veselina River, 25 km south-east of Veliko Tarnovo, 9 km south of Velchevo and 11 km west of Elena. The dam is rock-fill with a vertical clay core. The spillway is trench, 100 m long with an average width of 10 meters. The total volume of the embankments is 910,000 m ³. Its height is 66 meters and its length – 256 meters. The reservoir volume is 92 million m³. The effective volume is 82 million m³. The water was built up behind the dam during the period 1968 -1981. The storage began during the construction. The water intake tower has a circular cross-section with diameter of 9m and height of 70m.

Drinking water treatment plant "Yovkovtsi"
The Treatment plant for drinking water "Yovkovtsi" was built about 6km of Velchevo and purifies water from the Yovkovtsi Reservoir for Veliko Tarnovo, Gorna Oryahovitsa, Lyaskovets, Dryanovo, Elena, Strazhitsa, Zlataritsa, Polski Trambesh, Debelets, Kilifarevo and a number of settlements in the region.
Treatment technology is - prechlorination, sedimentation, filtration and disinfection.
DWTP "Yovkovtsi" has chemical and microbiological laboratories equipped with modern instrumentation. The laboratories employ highly qualified specialists. Two points of  a treatment plant are analyzed daily - input and output, one point in Veliko Tarnovo on 10 chemical and physicochemical indicators and 3 microbiological indicators. The same points are examined every week on 11chemical and physicochemical and 3 microbiological indicators, and once a month – on 20 physical and physicochemical indicators and 5 microbiological indicators. Along with the above analysis is conducted monitoring control together with RIOKOZ Veliko Tarnovo (Regional Inspectorate for Protection and Control of Public Health) and Basin Directorate – Danube region, located in Pleven – once a quarter at 11 points of dam "Yovkovtsi" on 27 indicators.
Once a month is conducted analysis of the waste water, technologically purified after WWTP before the debouchment in the Plachkovchitsa River in two indices and twice a year on five indices.
Periodically, at every four months tests are conducted at a chemical laboratory on the stability of the dam "Yovkovtsi" at four points in two indexes – stability in relation with total alkalinity and stability for active response.