Utility’s ice‑picking cleaning finds iron and manganese deposits; independent lab testing reported

Utility staff described a targeted mechanical cleaning program — referred to in the meeting as "ice‑picking" — to remove decades of scale and biological deposits from distribution piping. The utility contracted American Pipeline Solutions; staff said the initial mobilization and fee for 20 loads totaled roughly $347,000, and that additional loads would cost about $14,000 each.

"Every run had almost identical results," the presenter said, summarizing a third‑party laboratory analysis and real‑time sampling conducted during the work. For a May 8 cleaning run staff reported a turbidity reduction from 16.05 NTU to 4.95 NTU and said the single run displaced about 24,254 gallons of water. Chemical analysis cited to the group showed sample composition reported as approximately 40% manganese oxide, 30% iron oxide and 25% calcium carbonate.

The presenter acknowledged the cleaning reduced the number of color complaints but did not eliminate them. He described bacterial activity (manganese‑oxidizing and iron‑oxidizing organisms) that can shed material and create surges of red water; staff said those organisms are not a direct health hazard but can cause taste, odor and staining problems. The utility recommended in‑home filtration for customers most affected by discoloration and reiterated that the tariff process and UTC approval allow adjustments to a surcharge once final project costs are known.

Staff promised to post detailed lab results and the operational presentation on the utility website for customer review.