The city engineer and the water manager and chief engineer shall estimate the cost of the checking of plans for required improvements and of all general supervision and inspections required to ensure the proper installation and completion of all improvements in accordance with the city's general requirements therefor. The subdivider shall thereupon post with the city a cash deposit, in the amount so estimated, and, upon the completion of all the work, any amount not actually used shall be refunded to the subdivider or, if the fund is exhausted before the completion of all the improvements, the subdivider shall forthwith pay to the city an amount estimated by the city engineer and the water manager and chief engineer to be sufficient to cover completion; provided, however, if the subdivision is of such magnitude that the installation and completion of improvements will extend over a period in excess of one year, the subdivider may deposit an amount estimated to be sufficient for the first year, and the city shall bill the subdivider monthly as the work progresses, which amount shall be promptly paid by the subdivider until the city engineer and the water manager and chief engineer are satisfied that the total amount paid to the city will be sufficient to cover the costs of all general supervision and inspections by the city. (1962 Code § 10-903: amd. Ord. 75-O-1561, eff. 3-4-1975)