Special water and/or sewer projects which are paid in whole or in part by private citizen participation are authorized by prior agreement between the city and the residents or citizens of a geographic area in the municipality. Such projects may be constructed by private contractor and paid for in whole by the residents or citizens of the area or may be constructed by the city with the residents or citizens of the area paying for all or part of the expense of the project or improvement. In all events, written agreements between the city and the residents or citizens of the area shall be in existence and in the city's files before any construction start. (Ord. 1310, 4-16-1991)