Sigurd council hears plan to fix chlorination and tank plumbing; contractor work to begin

Sigurd Mayor Kelly Halvey and council members spent more than an hour on May 21 discussing a multi-part plan to fix long-running chlorination problems and plumbing between the town's new and older storage tanks.

The discussion centered on persistent failures in the town's gas-chlorine feed system and a large pressure differential across a valve near the chlorinator that has kept chlorine from consistently dosing the water. A utility technician who presented the plan said the town could add a small booster pump on an existing 1-inch bypass line and replace the current pilot/"clay" valve with an electronically actuated altitude-control valve tied to the tank level.

The technician said the changes would increase line velocity through the 1-inch PVC bypass so the chlorinator's venturi can pull gas chlorine reliably. "A small booster pump could be put on that 1 inch bypass," the technician said, and the altitude-control valve would open at a chosen set point (for example, when the tank level drops about 3 to 4 feet) and then close when the tank fills.

Nut graf: The proposed changes are intended to stop continuous chlorination of water that is being lost through the tank overflow, restore reliable chlorine feed to water entering the town system, and reduce the operational strain on an aging valve that has intermittently failed.

Council members and water staff discussed related work that also needs doing: installing a blow-off drain near the chlorination building so operators can easily drain the line between the two tanks, reworking exterior piping so the new tank can feed the older one through the chlorinator, and running power and control signals for the new valve and booster pump. The technician noted the chlorinator currently experiences atypical pressure loss "like 40 PSI," and said removing that head loss and adding the booster would allow the venturi injector to function.

Contracting and costs: the technician told the council that Barnes (a contractor referenced in the meeting) can perform the exterior piping and blow-off work and that he had spoken to Barnes already. He said Barnes was prepared to begin and that parts for the exterior work were in. The town was asked to cover the contractor's work. "We're planning on covering the cost of Barnes' work," the technician said, while the town would need to decide how much it could contribute toward the chlorination-specific components (the booster pump and control valve).

SCADA and controls: council members raised alarms and control-system reliability. The technician recommended integration of the electronic altitude valve with the town's SCADA (supervisory control and data acquisition) system and also described a hydraulic fallback if SCADA control is not yet reliable. Council members noted the SCADA system has sent frequent, confusing alarms and that a town technician ("Tyler" in the discussion) should be engaged to make sure alarm reporting and control signals will function when the new devices are installed. The council discussed arranging on-site work only when the SCADA/controls technician is available to help commission the valve and pump.

Timeline and operational impacts: the presenter said most of the plumbing and blow-off work could be done now and that when the valve and pump arrive they are straightforward to install. Contractors warned of a short, temporary interruption of the spring feed while connections are made; the presenter said storage tanks should balance the system and planned outages would likely be only a couple of hours and should not cause prolonged water service loss.

Next steps: council members agreed to have Barnes begin the exterior plumbing work and to determine the town contribution toward the pump and valve. They also agreed to bring Tyler into commissioning the SCADA connections. The technician said he would coordinate procurement of the booster pump and the electronically actuated altitude-control valve and report back on lead times and costs.

Ending: The council directed staff to coordinate a schedule with Barnes and Tyler, notify residents in advance of any brief supply interruptions, and to return with firm cost estimates for the booster pump and valve so the council could finalize funding.