The previous northern hall extension will be demolished in favor of an extension. Parallel to the northwest façade, a single-storey building block with a 25-meter warm-water pool and a plunge pool is being built; the new pools will extend the water area of the Alster swimming hall by around a quarter. Facing Ifflandstrasse to the north-east, the new building has two storeys with the entrance and changing rooms on the first floor and fitness and sauna areas on the upper floor. The entrance faces towards the Sechslingspforte and can be reached via a large forecourt to the north of the building. With the modernization of the Alster swimming pool into a sports pool, the fitness and sauna facilities will also be expanded. The sauna area with three large saunas and a separate women's sauna will be supplemented by a vitality bath with a steam bath, a calcium-lithium pool and a cold plunge pool.