Rogers wastewater plant sees extra February flow that staff says likely did not come from rain

Rogers Water Utilities staff told the Waterworks and Sewer Commission this week that the city’s pollution control facility handled significantly more flow in February than expected, even though rainfall was well below normal for the month. In the March 16 meeting packet, staff reported the plant treated 269.5 million gallons in February. Using a baseline of 9 million gallons per day, that would have totaled about 252 million gallons, meaning the facility processed roughly 17.5 million gallons of additional flow during the month.

What stood out to staff was the weather. The report says those February flows came during a month with just 0.24 inches of rain over two events, compared with a historical February average of 2.24 inches. Because of that, staff wrote that the excess flow was “pretty obvious[ly]” not caused by rainfall and was likely inflow from a creek of about 0.6 million gallons per day. The plant’s average daily flow in February was listed at 9.6 million gallons per day.

The February numbers appear to continue a pattern noted in the utility’s previous monthly report. Minutes from the commission’s February meeting show staff reported the plant treated 286.6 million gallons in January, including about 7.6 million gallons of inflow and infiltration, even though rainfall for that month was also below the historical average. In that earlier report, staff likewise concluded the added inflow was not being driven by rain alone.

While the commission’s March agenda included several action items, the flow issue surfaced in the Rogers Pollution Control Facility report, not as a standalone vote. Even so, the report points to an ongoing system concern: wastewater flow is entering the system from somewhere other than normal sanitary use, and staff now suspect a creek connection may be part of the problem.