Alamosa council reviews pilot to make arsenic‑removing chemical on site

Alamosa City Council on Tuesday reviewed a staff proposal to pilot an on‑site system that would produce a ferric reagent used to remove arsenic from the city’s drinking water. Staff said the technology, developed by Aquam Metrology Systems (AMS) and supported financially by Isle Utilities, could reduce corrosive impacts inside the plant and cut metals discharged to the wastewater system.

Harry, the city manager leading the Public Works presentation, told council members the current 2008 treatment plant meets state standards but relies on bulk ferric chloride that can be corrosive, has variable purity and presents supply‑security risks. Roy Saines, who runs Alamosa’s water treatment facility, described an in‑house pilot and said AMS’s on‑site generators produce a cleaner ferric reagent via electrolysis of certified steel plates.

The proposal calls for five generator units with an initial vendor price estimate of about $640,000 for equipment and commissioning; additional engineering and construction costs — including significant new electrical service — have not been finalized and staff estimated another $300,000–$400,000 could be required. The city currently has roughly $600,000 in its CIP earmarked for plant progression; staff said the existing funds could cover some initial engineering but not all potential construction upgrades.

Staff described Isle Utilities’ role as a financing partner that would loan funds to AMS to deploy the pilot in underserved communities. Under the arrangement described to council, Isle/AMS would cover upfront installation and risk; if the pilot meets promised performance and the state accepts the monitoring results, the city would be responsible for a buyout payment (staff cited an illustrative figure of about $40,000 in that scenario).

Roy said the facility’s small‑scale pilot in January 2023 showed arsenic removal “equal to or better than” the bulk ferric chloride currently in use and asserted the on‑site reagent could reduce the iron entering the distribution system by an estimated 38%, which staff said could lessen the wastewater plant’s future capital needs. He also said the on‑site chemical is “less corrosive” to internal plant components and that AMS would provide training and post‑installation support.

Councilors pressed staff on safety, oversight and contingency plans. One councilor asked how the city would detect and prevent a problematic batch if reagent production failed; staff said they would lab‑certify reagent batches, run in‑plant arsenic analyzers (with 10–15 minute readings), maintain the existing bulk ferric chloride as a backup and work under CDPHE oversight during a monitored trial. Staff repeatedly stressed that final approval would come from the state and that the trial length and acceptance criteria would be determined in consultation with engineers and CDPHE.

Councilors also discussed grant eligibility: because Isle/AMS would fund the upfront purchase to make the pilot risk‑free for the city, staff warned that some grants requiring prior expenditure or reimbursement may not apply. Staff estimated the city currently spends about $100,000 per year on chemical purchases and said the on‑site system could yield net savings over time, though several cost elements remain preliminary.

Several council members signaled cautious support for advancing to contract review and deeper technical study. Harry said staff requested only that council indicate whether it was interested in pursuing the project further; no formal vote or commitment was taken at the work session. The public comment period was opened and no members of the public spoke.

Next steps described by staff: if council supports moving forward, staff will pursue engineering designs by a Colorado‑licensed engineer, work with CDPHE on monitoring and trial requirements, review Isle/AMS contract terms, refine cost estimates for electrical and construction work and return to council for any purchase or formal approval.