(1)    Supervision of work. In exercising the powers granted by s. 30.30 (1) to (3) a municipality shall be governed by the law governing the laying out, improvement and repair of streets and bridges in such municipality, so far as applicable, except that no petition of property owners for doing any such work is necessary. If the municipality has established a board of harbor commissioners, such board shall be in charge of the work unless the board determines that it is not equipped to supervise the work and by resolution delegates such function to the agency which ordinarily performs such function for the municipality. If the municipality does not have a board of harbor commissioners, the municipality’s board of public works or, in the event there is no such board, the municipality’s governing body shall be in charge of the work.

   (2)   Work requiring approval of state or federal government. No work for which the approval of the department or of the United States is required shall be commenced unless the plans and specifications for such work have been submitted to and approved by the department or the proper officer of the United States, as the case may be. When the plans and specifications have been so approved, the work shall be done only in accordance with such plans and specifications.

   (3)   Government aid in dredging of harbor channels and flood control projects. Whenever the U.S. government indicates its intention to aid in any flood control project or in the improvement of any harbor by dredging of harbor channels at federal expense, subject to the proviso that the local interests save the federal government harmless from all liability and claims for damages resulting from such project or dredging, the governing body of such municipality may, by resolution, assume liability for and on behalf of both public and private ownership adjacent to, within, under and over the channels, land area and construction works in flood control projects, involved in such federal projects. Such municipality may provide adequate insurance coverage, indemnifying such municipality for all damage resulting from such project or dredging.

   (4)   Acquisition of land. In acquiring land by condemnation for any of the purposes specified in this chapter, a municipality shall be governed by the law relating to condemnation of land for public grounds or street purposes. Whenever land is acquired through a land contract arrangement, such contract may create a lien on such lands for the purchase price and interest thereon but shall not create any liability therefor on the part of the municipality.

   (5)   Cooperation among municipalities. Whenever 2 or more municipalities propose to cooperate in erecting, maintaining or repairing a dock wall or shore protection wall, their governing bodies shall first meet and adopt a method of proceeding and a plan of apportioning to each its share of the entire cost. Such method of proceeding and plan of apportionment shall be embodied in a resolution adopted by the governing bodies of the cooperating municipalities acting jointly and later such resolution shall be adopted by each of the governing bodies acting separately. Municipalities acting under this section shall have the powers conferred by s. 66.0301.

   (6)   Special assessments. Special assessments for benefits to lands, when authorized by s. 30.30 (4), shall be made and enforced as provided by s. 66.0703, except that at any time within the 90-day period immediately following the publication of the final resolution as required by s. 66.0703 (8) (d), the owner of any property along which such improvement is to be made may elect to make the improvement along the owner’s property at the owner’s expense in accordance with the approved plans and specifications or in a manner which conforms to good engineering practice and which provides for materials and designs which, with respect to strength and permanence, are at least equal to the requirements of the approved plans and specifications. If the owner makes the improvement at the owner’s expense, no assessment of benefits shall be made therefor. If such owner fails to commence the work within the 90-day period specified herein or fails to carry on and complete the work with due diligence, the work may be done or completed by the municipality and assessment of benefits made therefor.

   (7)   Building permits for marine shipping structures. Before any permit for building or improving any structure directly affecting marine shipping is issued by a municipality or any of its departments, the plans therefor shall be submitted to the municipality’s board of harbor commissioners, if any. If the board finds that the location or design of the structure will adversely affect the orderly development of the harbor or the orderly movement of traffic to or within the harbor, the board may disapprove the plans, giving its specific reasons for such disapproval. No permit for building or improving any such structure shall be issued until the plans therefor have been approved by the board of harbor commissioners. The governing body of the municipality may delegate to the board of harbor commissioners the power to issue permits for construction of dock walls.