The project concerns the extension of the drainage system of rainwater and meltwater from the city of Leszno. The need for implementation of the project stems from the Programme for Waste Water Management and the Development of Rain Sewerage for the city of Leszno. The following investment tasks will be carried out within the scope of the project: 1. Construction of the “Eastern” rainwater manifold together with retency and infiltration tanks. The investment task consists of the construction of a rainwater manifold – so-called. “Eastern” and two retency and infiltration tanks together with a water treatment plant for rainwater. The primary function of this task is to create a new receiver for rainwater drains from the northern and eastern parts of the city. 2. Expansion of the eastern rainwater manifold on the section from Rond Antonina to the PKP tracks. The scope of the task includes the extension of the rain drainage network – the “Eastern” manifold on the section from Rond Antonina to the railway tracks in the area of Kasztelańska and Rycerska Streets in Leszno. The investment area is designed to connect Al. The Constitution of May 3 from ul. Gronowska in Leszno. Ultimately, the rain collector will be used to drain the newly designed road connecting Al. The Constitution of May 3 from ul. Gronowska and will be burdened with the flow of rainwater from a part of the Gronowo settlement. 3. Construction of a storage tank at ul. The European Union in Leszno. The location of the reservoir on plot No 27/27 results from the findings of the “Programme for rainwater management and development of rainwater drainage for the city of Leszno”. The construction of a watertight reservoir with damped water drainage into the existing rainwater drainage system was adopted.