When the council determines to make any improvement, it shall let the contract for all or part of the work, or order all or part of the work done by day labor or otherwise as authorized by subdivision 2, no later than one year after the adoption of the resolution ordering such improvement, unless a different time limit is specifically stated in the resolution ordering the improvement. The council shall cause plans and specifications of the improvement to be made, or if previously made, to be modified, if necessary, and to be approved and filed with the clerk, and if the estimated cost exceeds the amount in section 471.345, subdivision 3, shall advertise for bids for the improvement in the newspaper and such other papers and for such length of time as it may deem advisable. If the estimated cost exceeds twice the amount in section 471.345, subdivision 3, publication shall be made no less than three weeks before the last day for submission of bids once in the newspaper and at least once in either a newspaper published in a city of the first class or a trade paper. To be eligible as such a trade paper, a publication shall have all the qualifications of a legal newspaper except that instead of the requirement that it shall contain general and local news, such trade paper shall contain building and construction news of interest to contractors in this state, among whom it shall have a general circulation. The advertisement shall specify the work to be done, shall state the time when the bids will be publicly opened for consideration by the council, which shall be not less than ten days after the first publication of the advertisement when the estimated cost is less than twice the amount in section 471.345, subdivision 3, and not less than three weeks after such publication in other cases, and shall state that no bids will be considered unless sealed and filed with the clerk and accompanied by a cash deposit, cashier's check, bid bond, or certified check payable to the clerk, for such percentage of the amount of the bid as the council may specify. In providing for the advertisement for bids the council may direct that the bids shall be opened publicly by two or more designated officers or agents of the municipality and tabulated in advance of the meeting at which they are to be considered by the council. Nothing herein shall prevent the council from advertising separately for various portions of the work involved in an improvement, or from itself, supplying by such means as may be otherwise authorized by law, all or any part of the materials, supplies, or equipment to be used in the improvement or from combining two or more improvements in a single set of plans and specifications or a single contract.
In contracting for an improvement, the council shall require the execution of one or more written contracts and bonds, conditioned as required by law. The council shall award the contract to the lowest responsible bidder or it may reject all bids. If any bidder to whom a contract is awarded fails to enter promptly into a written contract and to furnish the required bond, the defaulting bidder shall forfeit to the municipality the amount of the defaulter's cash deposit, cashier's check, bid bond, or certified check, and the council may thereupon award the contract to the next lowest responsible bidder. When it appears to the council that the cost of the entire work projected will be less than the amount in section 471.345, subdivision 3, or whenever no bid is submitted after proper advertisement or the only bids submitted are higher than the engineer's estimate, the council may advertise for new bids or, without advertising for bids, directly purchase the materials for the work and do it by the employment of day labor or in any other manner the council considers proper. The council may have the work supervised by the city engineer or other qualified person but shall have the work supervised by a registered engineer if done by day labor and it appears to the council that the entire cost of all work and materials for the improvement will be more than the lowest amount in section 471.345, subdivision 4. In case of improper construction or unreasonable delay in the prosecution of the work by the contractor, the council may order and cause the suspension of the work at any time and relet the contract, or order a reconstruction of any portion of the work improperly done, and where the cost of completion or reconstruction necessary will be less than the amount in section 471.345, subdivision 3, the council may do it by the employment of day labor.
As an alternative to the procurement method described in subdivision 2, the council may issue a request for proposals and award the contract to the vendor or contractor offering the best value as described in section 16C.28, subdivision 1, paragraph (a), clause (2), and paragraph (c).
When the council has performed construction work by day labor, it shall cause a detailed report to be filed with the clerk and certified by the registered engineer or other person in charge, if there is no registered engineer. The report shall show:
(a) the complete cost of the construction;
(b) final quantities of the various units of work done;
(c) materials furnished for the project and the cost of each item thereof;
(d) cost of labor, cost of equipment hired, and supervisory costs.
The report shall have attached a certificate by the registered engineer or other person in charge that the work was done according to the plans and specifications, or, if there were any deviations from them, an itemized statement of those deviations.
As to any improvement or improvements consisting of grading, graveling, or bituminous surfacing of streets and alleys, the council may proceed in the manner provided in this chapter, except that it may
(1) order the work done by day labor, regardless of the estimated cost of such improvement or improvements,
(2) use municipal equipment or hire equipment and purchase materials for all such improvements to be done by day labor in any 12-month period by advertising once therefor, such advertisement to call for bids for the furnishing of equipment, if the municipality does not use its own equipment, and for materials at unit prices based on the quantities which the council estimates will be required, and
(3) contract at one time on a unit price basis for part or all of the street improvements to be constructed by the municipality during the current year, including improvements which may thereafter be ordered constructed.
When an improvement is made under a cooperative agreement with the state or another political subdivision by the terms of which the state or other subdivision is to construct or contract to construct the improvement, it shall not be necessary to comply with subdivisions 1 and 2.
In case the contractor properly performs the work, the council shall, from month to month before completion of the work, pay the contractor not to exceed 95 percent of the amount already earned under the contract, upon the estimate of the engineer or other competent person selected by the council, and the contract shall so provide, and shall further agree that when the work is 95 percent or more completed upon the recommendation of the engineer such portions of the retained price shall be released as the governing body of the municipality determines are not required to be retained to protect the municipality's interest in satisfactory completion of the contract. Failure to pay any amount due and payable under the terms of the contract within 30 days of a monthly estimate or 90 days after the final estimate of the amount earned shall obligate the municipality to pay to the contractor simple interest on the past due amount at an annual rate equal to the monthly index of long term United States bond yields for the month prior to the month in which this obligation is incurred plus an additional one percent per annum. Interest shall not be imposed with respect to any amount which a municipality may legally withhold as a result of breach of contract or other contractual claim or if the delay is caused by the contractor.
After work has been commenced on an improvement undertaken pursuant to a contract awarded on a unit price basis the council may, without advertising for bids, authorize changes in the contract so as to include additional units of work at the same unit price if the cost of the additional work does not exceed 25 percent of the original contract price. Original contract price means that figure determined by multiplying the estimated number of units required by the unit price.