The contract includes the planning services of civil engineering structures according to § 41 ff HOAI in conjunction with Annex 12 HOAI – civil engineering structures, work phases 2-9 for the new construction of the combined sewer in Titisee.

The city of Titisee-Neustadt plans to renew a mixed water collector from Titisee to Neustadt in the medium term. For the planned project, a variant study 04/2021 was carried out. The study examined whether the combined water relief above and in the area of the water protection area can be further reduced or prevented. As a result, it turned out that due to the water management advantages, the new construction of the mixed water collector will be pursued. As a result of the variant study, the existing main collector is to be renewed over a length of approx. 1.7 km in DN 1200. It is envisaged that the new sewer will then be reconnected to the existing sewer system including a new relief point. Nevertheless, the existing main collector will remain in operation. During planning, difficult-to-access route sections and ecological constraints must be taken into account.