Water Resources Consortium – Scheme 23 – Florence


    Sieve River, Province of Florence (Italy)

The Bilancino Revervoir has been planned and built with the aim of reduction flood risk for Florence City after the events of November 1966.

The Reservoir

  • Capacity 62,5 hm3, with an additional volume of 2,5 hm3 or possible mud silting
  • Average yearly available water supply of 55 ×106m3 for the city of Florence and for the nearby Prato area
  • A noticeable flood control (15 ×106m3 volume) for the most dangerous events occurring in autumn

Main Features of the Dam

  • Type: zoned earthfill dam
  • Normal water level at elevation 252,0 m a.s.l.
  • Maximum water level at elevation 254,5 m a.s.l.
  • Minimum water level at elevation 234,5 m a.s.l.
  • Maximum height :42 m
  • Crest length :720 m
  • Spillway: ungated type

Foundation Soils

The reservoir area corresponds to the eastern sector of an ancient Pleistocene Lake – the Mugello Lake – which was definitively drained by the Etruscans. Miocene sedimentary formations, like marly limestone and siltstone, locally called Macigno and Alberese, are prevailing. The bedrock is covered with clayey deposits of lacustrine origin and with recent alluvium. The dam foundation consists of thin layers of fine sandstone, silties and over-consolidated silty clays.

Services provided by the technicians of Sering

  • Feasibility Study
  • Detailed Design
  • Assistance to Supervision of works