Record flooding tests resilience of Midwest water systems

Despite the devastating economic and human losses caused by the heavy rainfall and rapid snowmelt that choked waterways, circumstances would have been worse without emergency preparedness and planning, say American Water Works Association (AWWA) members from Nebraska who shared their experiences.

“The main thing that helped us was planning,” said Dennis Watts, water and sewer director with the City of Norfolk, Neb., and the AWWA Nebraska Section’s representative with the Nebraska Water/Wastewater Agency Response Network (NEWARN).

“Our wells are all built above the 150-year flood plain, and without this forward thinking when the wellfield was put into production our water supply would have been in jeopardy,” he said. “I can’t stress enough the importance of this type of planning in infrastructure design and build.” (Flood photo courtesy of City of Norfolk)

Watts (pictured left) explained that the Norfolk Water Department applied lessons learned from a 2010 flood into its flood emergency plan which, coincidentally, employees reviewed just three weeks prior to this spring’s emergency.

“As soon as we heard of possible flooding we started watching the Elkhorn River, so we could take necessary precautions as needed,” he said. His department closed off collection well valves leading to a local aquifer to prevent contamination and de-energized power to the well closest to the rapidly-rising river.

Southeast of Norfolk in Omaha, Neb., the Metropolitan Utilities District (MUD) was armed with recently-developed plans to address emergencies and business continuity.
“I think we were adequately prepared in most regards,” said Jim Shields, MUD’s vice president of water operations. “All three of our treatment plants remained in operation during the flooding and we were able to meet our customers’ demands for water and stay within all treatment regulations.”

MUD’s biggest challenges were the floodwaters threatening its two plants on the Platte River and a major runoff event at their Missouri River plant that impacted treatment processes.

“We had to shut down power to the wellfield at the smaller of the Platte River plants once the water rose high enough to partially submerge the transformers,” Shields said, adding that the facility remained in service at a third of its capacity because some wells had emergency backup natural gas engines that were mounted above the flooding.

“We struggled, especially overnight, to know exactly where the water level had risen to as we could not enter the area,” he said. “We later used an employee’s drone to monitor our flooded wellfields and found it to be very useful; I’m sure we will have a company drone soon.”

Once the flood waters receded, there was much more work to be done, including clearing out the mountains of sand burying the plant roads to well houses. (At right, MUD photo of well road impacted by flood debris)

“Ongoing recovery at the more severely flooded location required a meticulous inspection and cleaning of all flooded electrical components, bridge inspections, debris cleanup, road repair, washout repairs and sand removal,” Shields said.

Bruce Dvorak, director of the AWWA Nebraska Section, said the ongoing opportunities presented by AWWA at the section level “worked in advance to help our members network and build relationships, which were essential when utilities were put under stress by the flooding. This included connections with the Nebraska Department of Health and Human Services and partnerships through NEWARN.”