1. the laying out of streets, avenues and alleys:
2. the straightening and widening of streets, or changing the grade thereof;
3. the constructing or repairing of sidewalks, sewers, and other improvements;
4. the securing of land for parks, cemeteries, schoolhouses, fire departments, market houses, and for the constructing of any public building;
5. the laying out, constructing, erecting or perfecting of levees, or a system of levees, for the protection of such municipality or any part thereof, or for the protection of any public work or building, and for the constructing or perfecting of its drainage system;
6. the establishing, altering and changing of the channel of streams or water courses or ditches, and the acquiring of land to bridge the same;
7. and in any other case where the land is to be used for public purposes.