I-6 - Resolution 2025-012 - Substantial Completion for Well 5 Pump, Controls and Watermain Project

MEMORANDUM To: Doug Boldt From: Dave Schechinger Re: Well 5 Extra Cost Date: 12/26/2024 V&K No: 5093 Construction of the well 5 raw water main was complicated by contamination of the water line during construction. Numerous attempts were made by the contractor to clean, flush, disinfect and ultimately replacement of the water line to address the contamination issue. During the contractor’s efforts to disinfect the water line, the City collected samples and delivered them to the testing laboratory for evaluation. Well 5 was operated to flush the main and water from the finished water system was also used to flush with chlorinated water. Ultimately, 132 tests were collected and submitted to the laboratory for testing. The cost for the test was $17.50 per test. In addition, the City had a cost to transport the test from the project site to the laboratory. That trip is estimated to be approximately 4 miles from the City water plant to the University of Iowa Hygienics Laboratory or 8 miles round trip. There were reports provided for 85 different days of testing with some days containing multiple tests. This equates to 680 miles of travel for testing. In addition to testing cost, the City incurred cost for operating the well without beneficial use for approximately one year. During that time, the City also incurred cost in the form of emergency repair rates to repair well 4. This was necessary since Well 5 was not available to allow repairs to be conducted at regular rates when the well contractor was available. The emergency repair rate cost impact is estimated to be approximately $5,000 above what would have been charged for the repair under non-emergency conditions. The extra cost to operate Well 5 for the disinfection period was determined by estimating the additional cost above normal operating cost for Well 5 during that period. The cost is estimated to be $4,036.40. The City is in the process of planning upgrades to the water treatment facility. A pilot system was operated for reverse osmosis treatment beginning in June of 2023. The timing of the pilot system was planned to coincide with completion of Well 5 so that source water from Well 5 could be evaluated with the pilot study. The City reports that roughly 5 weeks of downtime on the pilot study occurred due to the issues with disinfection of the Well 5 raw water main. This cost impact is not easily categorized and the City has opted to not pursue reimbursement for the extra cost incurred.