PALTINU LAKE AND DAM, DOFTANEI VALLEY, EMARALD LAKE WITH TURQUOISE WATER, CIUCAS PALTINU MEADOW

Paltinu Dam is located in Prahova County, on the valley of the Doftana river, downstream of its confluence with the Paltinoasa valley, in the gorges called "La Tocile".
In the dam section, the valley has a profile characterized by a pronounced asymmetry. On the left bank, there is a terrace with a width of about 100 m. The bedrock consists of sandstone with intercalations of marly and clayey shales. The bedrock is crossed by several faults and a complex system of cracks.
Due to the difficult geomorphological conditions of the site, the variant of an arched concrete dam with double curvature with perimeter purpose was adopted. This solution involved making an extended foundation plinth on the left bank with a parabolic wing. This base allows a symmetry of the section in which the dam itself is executed and allows a better takeover of the differences of the elastic modulus of the rock on the two slopes. Also, the plinth allowed a better adaptation to the local geological conditions, by filling the areas with altered rock. The foundation ground was strengthened by a sealing veil made by injections of cement milk. Between the parabolic dam and the left slope, a concrete abutment was also made, which contributes to a better cooperation of the dam with the slope.
The dam has a height above the foundation of 108 m., The canopy of the dam being at an altitude of 654 mdm., The total length of the canopy of the dam is 455 m.
For stabilization, consolidation works were also performed on both sides by anchoring with prestressed cables.
Despite all these works, during the first filling of the lake, large infiltrations were found under the base, exceeding 150 l / s and displacements of the structure at the contact between the central arch and the parabolic wing. As a result, various additional works were carried out, including the supplementation of the sealing veil, the amplification of the drainage system and the covering of the downstream part of the left slope with concrete blocks in steps of 6-8 m, anchored in depth with prestressed cables.
With these measures, the infiltrations stopped and the behavior of the dam and the slopes remained within admissible limits.
The execution works of the Paltinu dam started in 1966, the dam being put into operation in 1971. A second stage of consolidations was executed between 1976 - 1982.