Menu

Flood Recovery for Water and Wastewater Utilities: What Indiana Operators Need to Know

News

Flooding can disrupt every part of a utility, from the distribution or collection system to the treatment processes and electrical systems. The aftermath of a flood can be stressful for water and wastewater operators, but resources such as the U.S. EPA’s Flood Resilience Guide and Indiana University’s Environmental Resilience Institute provide guidance on how to protect your utility against flooding. This article summarizes that guidance and immediate actions operators can take after flood waters recede.

Start with Safety and Documentation

The first priority during any severe weather event should be safety. Before reentering any flooded area, operators should look for hidden hazards such as energized equipment, unstable structures, damaged walkways, chemical spills, and debris. Electrical isolation should be verified before anyone enters affected areas or attempts to restart equipment. Operators should remain vigilant of their surroundings while inspecting flood-damaged areas and stay up to date on weather conditions.

Once the site is safe, document conditions with photographs, video, field notes, and a written summary of visible damage. Clear documentation is essential for IDEM reporting, FEMA reimbursement, insurance claims, and future resilience planning.

Wastewater Recovery Priorities

Wastewater treatment plants are commonly located near a receiving water and are often on the front lines during heavy rainfall and flooding. Inflow and infiltration can lead to hydraulic overload from upstream, while flooding can encroach from downstream. Submerged equipment, damage from floating objects, and power loss can quickly affect treatment performance. Once the site is safe, operators should focus on stabilizing core processes, including screening, clarification, aeration, pumping, and disinfection.

Water-exposed equipment should be dried, cleaned, inspected, and tested by qualified personnel before it is energized. This includes motors, pumps, blowers, MCCs, VFDs, and SCADA components. Operators should also evaluate whether biomass washout occurred and determine if activated sludge systems need to be reseeded.

Chemical storage areas also need close attention. Tanks should be checked for dilution, leaks, flotation, or damaged secondary containment. If floodwater reached chemical feed systems, verify that dosing equipment is safe, accurate, and ready before returning to normal operation.

Drinking Water Recovery Priorities

For drinking water treatment plants, recovery begins with raw water quality. Flooding can cause turbidity spikes and introduce microbial contamination, sediment, fuel, agricultural runoff, or industrial pollutants. Operators should collect samples and test turbidity, E. coli, and hydrocarbons before restarting intake pumps.

Treatment process components should be carefully examined. If silt entered filters or media, operators may need extended backwashing cycles or rehabilitate the filters completely. If floodwater entered a clearwell or backflow occurred, the clearwell should be drained, cleaned, disinfected, and verified before use.

Distribution system recovery is just as important as plant recovery. System flushing, chlorine residual verification, and post-event sampling help confirm that water leaving the plant remains safe as operations resume.

Build Resilience Before the Next Flood

Recovery should lead directly into preparation for the next event. Utilities can reduce future damage by elevating electrical equipment, protecting critical assets with barriers or berms, securing chemical tanks, improving site drainage, adding backup power, updating emergency SOPs, and training staff on flood response procedures. Communities can also consider run-on controls, retention structures, and green infrastructure to reduce flood impacts over time.

Flooding will always create challenges for water and wastewater utilities, but preparation helps operators respond safely, recover faster, and protect the communities they serve. By turning lessons learned into stronger plans, utilities can reduce downtime, improve resilience, and be better prepared when the next major storm arrives.

Commonwealth Engineers stands ready to assist Indiana and Kentucky communities with any treatment plant operations questions. For more information, contact: cei@contactcei.com

|