The need to build a Tassi multifunctional drainage plant is justified by the need to keep water quality, quantity and ecological risks as low as possible. After the destruction of the former Tassi water draining artifact in 1956, water drainage is carried out through the Tassi lock as a necessary solution. Needs and shortcomings that underpin the need for the implementation of the Tassi multifunctional drainage artefact: — The amount of water flow that can be passed through the existing drainage artifact is insufficient and it is not technically possible to adapt it in that direction. The necessary amount of water flow can be provided by the construction of a new artifact. — Currently the pumped water transfer capacity in the Danube flooding situation is insufficient. This insufficient capacity can only be ensured by the occasional assembly of a mobile pump station. It is therefore necessary to provide a pumping capacity that is permanently installed and carries water more than at present. — During a long rain-free period, when there is a significant need for irrigation water in the low Danube water level, the natural water supply of the RSD is practically eliminated, the water supply can only be provided by the Kvassay lock, but in addition to the low Danube water level, it can only supply this in a pumped plant with limited flow. At the same time, there is a significant need for water abstraction on main irrigation channels that are branched out of RSD. There is a need to build pump capacity (Danube › RSD) in the opposite direction to the discharge water (RSD › Danube). — The water supply of RSD is carried out only in a controlled manner from the Danube during an inland watertight period with water entered at the Kvassay lock. However, if the Danube water level is lower than the operating water level of the RSD, this can only be done in a pumped plant with significant operating costs. During gravitational drainage at the Tassi multifunctional drainage structure, the available water strength potential can be used to reduce the operating cost of the system. Expected results and effects of the construction of the artifact — Improving water flow, water level control; — Increase the security of water sharing; — Increase the quantity of Danube feed water introduced with a view to improving water quality; — Provision of drainage capacity at Tass in accordance with water use needs; — Enabling power generation in drainage mode; — The artifact, as part of the Danube’s main flood protection line, ensures that floods of the Danube are excluded from RSD. To support the laboratory measurement element of the monitoring system, equipment procurement was planned in the project. Measurements by these tools will help to demonstrate the results and impacts of the project during the maintenance period. Due to the phase-out, the closure of the project is delayed compared to the planned, which entails the start of the maintenance period and a later date for the provision of maintenance and operating costs to cover the inspection costs. Significant improvements in water quality and water management could be ensured by implementing all the interventions planned under the project. Thus, during the first phase, it is not technically relevant to carry out the purchase of equipment to support the monitoring system, which was moved to the second stage.