Bullhead City reviews $60–$70 million plan to repair and expand wastewater system

Utilities Director Mark Clark told the Bullhead City Council on April 1 that Bullhead City faces roughly $60 million to $70 million in capital wastewater projects to repair aging lift stations and upgrade the Section 10 wastewater treatment plant.

The plan addresses multiple immediate failures and longer-term expansion needs, including replacement of failed clarifier equipment, construction of a new headworks with odor control, installation of a large emergency generator, replacement of corroded pipe with PVC, and the staged expansion of plant capacity from 4 million gallons per day to 6 million gallons per day.

Clark said several projects are already under construction and others will require equipment orders this year because of long lead times. "There’s a nine-month lag between when we order and when we receive the equipment," Clark said, adding that the city will not incur payments on much of the work until after July 1 because the purchases are included in next year’s capital budget. "We believe that, we’re gonna have somewhere in the neighborhood of 60 to $70,000,000 worth of capital projects," he said.

Why this matters: Council members and residents have expressed concern about odors, structural failures and the risk of more frequent system outages as equipment nears the end of its service life. Clark said the city is responding both to an Arizona Department of Environmental Quality consent order that flags needed repairs and to repeated failures at high-priority sites.

Most urgent repairs and staging

Clark outlined current and planned work at the Section 10 wastewater treatment plant. Two projects under construction now are the new headworks and associated odor-control systems; Clark said the headworks foundation and basement have been poured and a slab for the main floor will be poured within weeks. The city purchased Heber bar screens sourced from Germany for the new headworks to reduce ragging in the system.

Clarifier number 2 experienced a recent failure; Clark said temporary equipment is being installed while the city orders permanent replacement hardware. The city plans to construct a new clarifier (clarifier no. 3) next year, then sequence rehabilitation of clarifiers 2 and 1 so the plant can remain operational throughout repairs.

Clark said the oxidation ditch — last rehabilitated in Feb. 2007 — requires a full rehab including new pumps and motors. He told council the oxidation-ditch equipment is being requested for order this year to meet the nine-month manufacturing lead time. "We're not sure what we're gonna find once we actually start emptying this oxidation ditch and beginning the rehab work on this," Clark said, noting the city will not know the full scope until the ditch is dewatered.

Lift stations and pipe corrosion

Several large lift stations are under repair, including Lift Station 18-1 and 18-2. Clark showed photographs of concrete deterioration and exposed rebar and said some wet wells required extensive rebar replacement and placement of new structural matting. For one lift station project the city both rehabilitated and expanded the wet well and installed screening ahead of pumps to reduce ragging.

Clark said the city will replace corroded ductile-iron piping with PVC in many places because hydrogen sulfide gas in the headspace is corroding the pipe. He described steps the utilities department is taking to reduce odors and corrosion, including installing "Wet Well Wizards" (air-injection devices that promote aerobic bacteria), oxygen and H2S monitors, and activated carbon scrubbers where needed. Clark said the 104 Lift Station by Rotary Park will receive an activated carbon scrubber within the next month or two.

System expansion and staging

Clark said the Section 10 plant capacity is being expanded from 4 million gallons per day (mgd) to 6 mgd to accommodate population growth. He described the work as "dominoes" that must be staged: building an additional aeration basin so the city can empty and rehab the oxidation ditch, then rotating flow through clarifiers during sequential rehabs.

Timing, costs and procurement

Clark emphasized procurement timing for long‑lead items. He said the city will place orders this year so equipment can be delivered and installed next year, and that many purchases will be included in the coming year's capital budget. On logistics, he said a large emergency generator will require four semi trucks for delivery.

Public comment and council questions

Resident Harvey Pryor asked whether concrete had been coated with a moisture or acid-resistant barrier when prior rehabilitation work was done. Clark replied, "We do put coatings on the concrete. But as I said, last time that was rehabbed was Feb. 2007," and said the primary damage to exposed concrete is caused by hydrogen sulfide gas rather than liquid contact.

Next steps and council action

Clark said staff will return with formal purchase and contract requests for council approval on upcoming agendas to meet equipment lead times. After the work session concluded, the council voted 7–0 to move into an executive session. Mayor Toby Cotter announced the body would reconvene at 5:30 p.m. for the regular meeting.

The presentation made clear the city faces both urgent repairs to aging, failing infrastructure and multiyear expansion work that will require substantial capital funding and careful staging to avoid service interruptions.