The Tiszaroff flood overflow reservoir, constructed by COLAS-ALTERRA, was handed over on 9 July 2009. The reservoir is located between the villages of Tiszaroff, Tiszabő and Tiszagyenda, thus directly enhancing the flood safety of 5300 inhabitants and 2000 households, additionally having an influence on flood safety in the entire Tisza River Valley. The reservoir will hold 97 million m3 of water, and with its area of 22.8 km2 it is comparable to Lake Velence in size. The reservoir is surrounded by 23.1 km of embankments, 8.8 km of which was part of the existing Tisza flood-control earthworks, while the remaining 14,9 km is newly built. The average height of embankments is 4.5 m, their crown is 5 m wide. A 3 m wide service road (also available for cycling) was constructed on the entire length of the embankment crown.

Water from the River Tisza is transferred into the reservoir through two vast floodgates (the so-called intake and outlet structures). The northern structure is capable of transferring 300 m3 of water per second. Water is led in and out through three 8 m wide openings, which are sealed by removable so-called segment plates operated by electric motors. With its 3 openings, so-called roller-flat slab sealing, and a capacity of 150 m3/s, the primary role of the southern structure is discharging the reservoir.