Mutual agreements are private drainage systems – there is usually no involvement of the local municipality or a government authority, unless they are associated with the agreement as landowners. The S104 agreements concern the maintenance of sewers contained in a new development by the local water company, to the detriment of the sewerage authorities. The agreement that they authorize the implementation of a drainage system. The process is subject to strict rules, such as . B the obligation to carry out flood risk assessments, with significant cost implications. It is therefore worth getting specialized advice before applying. Mutual agreement – must have the seven attributes defined in section 2 of the law, but it is written in the title deed. These agreements are binding on all current and future owners. The adoption process has recently been complicated by the private laying of channels, which took place in 2011.