Flood water stagnation poses a public health problem
Sunny skies returned to El Paso this week after Sunday’s monsoon storm that left parts of the city’s East Side submerged in floodwater. But water safety experts and city officials have warned that calm waters still pose a threat.
“(Standing water) could contain certain types of contaminants or debris below the surface that can cause injury,” said Kristina Mena, water safety expert and campus dean of the UTHealth School of Public Health in El Paso. . “It’s best to avoid, and not wade into, play in, or walk a pet through.”
Stagnant water remained in some days in the city after the storm, including at Album Park, where city crews pumped stagnant water from the mini lagoon resulting from the downpour.
More than three inches of rain fell in an hour in Sunday’s storm.
Floods are the second deadliest natural disaster after heatwaves, according to the Centers for Disease Control and Prevention. Flooding in the streets of El Paso on Sunday washed away cars and saw water three to four feet deep, but left no injuries, a spokesperson for the city’s fire department said.
Beyond the immediate impacts, floodwaters can carry pathogens, wastes and waterborne pollutants.
Angela Mora, director of the El Paso City Public Health Department, said standing water can harbor bacteria, viruses and parasites, all of which can cause diarrheal illnesses.
“Exposure to contaminated water can also cause tetanus-related rashes and wound infections. Contamination of wounds and lacerations in humans and animals can trigger infections that can spread to other parts of the body, ”she said.
Mora said another concern with standing water is mosquito breeding. She said homeowners should remove all items that could collect water and work with vector control experts to eliminate mosquitoes, and people should wear repellents and take other mosquito precautions.
El Paso Water officials said all stormwater collected in the Rio Grande, the city’s main water source, can be treated by their factories.
“Our river water treatment plants can effectively treat any water that may come from storm water runoff to meet or exceed federal and state drinking water standards,” El Paso Water officials said in a statement sent. by e-mail.
More rain could be in store for the Borderland.
Meteorologist Jason Grzywacz of the National Weather Service El Paso forecast office said Sunday’s storm was a typical monsoon pattern, which occurs between late June and September.
“If anything, this storm itself wasn’t strong, it stayed in one place for a long time,” Grzywacz said.
The areas that received the most rain included Montana Avenue between Hawkins Boulevard and McRae Boulevard, which received 3.45 inches. Grzywacz said the current forecast is for a dry week through Thursday, with chances for a rainy weekend ahead.
But threats to the stormwater system come not just from the rainy seasons, experts said, but the threat posed by climate change by making rainstorms stronger and more frequent.
Ben Hodges, an engineering professor at the University of Texas at Austin, called the Texas thunderstorms “water bombs” that prevent cities from preparing for floods.
“There’s so much water coming down in such a short time that removing that volume is very, very difficult, especially the cost of making this design for these, it’s just impractical. And so we don’t do it, ”he said.
Hodges said three key issues face local stormwater utilities: many cities have aging infrastructure that is not up to modern standards; the United States faces increased flooding from more severe storms due to climate change; and there are no answers on how more frequent floods could impact the water quality of communities.
“You wash the sediment, you wash the pollutants, you wash whatever is in the parking lots,” he said. “And this is all going to end in the second round. So yes, these are all huge issues that are really not well resolved. “
El Paso Water designs stormwater projects to capture and return rainwater based on a 100-year storm, or precipitation totals that have a 1% chance of falling in the area. The use of a 100-year storm is a recommendation of the Federal Emergency Management Agency.
Christina Montoya, communications and marketing manager for El Paso Water, said limited budgets mean these standards are being gradually implemented.
“Designing projects at a higher standard results in a much more expensive installation and therefore higher costs,” said Montoya.
She gave the example that some projects would start with 25-year storm protection and then, in later phases, move to a 100-year storm protection level.
“We’re still going to get through that initial set of projects where our stormwater system just hasn’t been considered historically,” Montoya said. “We are catching up, we are trying to do as much as possible.”
El Paso water officials also said the arid area and mountain slopes contribute to flash flooding and rockfall causes debris that needs to be cleared from the canals. Montoya said maintenance and construction are funded by stormwater charges collected by the utility, although federal and state grants also provide the money.
“The most difficult problem we have is completing the improvements while being mindful of the need to keep stormwater rates low based on public feedback,” officials said in an emailed statement.
Matt Bartos, an assistant professor of environmental and water resources engineering at the University of Texas at Austin, said increased urban growth and older amenities are compounding climate challenges.
“Stormwater management infrastructure designed to handle historic rainfall patterns will fail to keep pace with the demands imposed by future storms,” he said. “This does not mean that we are totally doomed. There is enormous potential to transform our existing stormwater infrastructure to meet the challenges posed by climate change and other future stressors.
Bartos said some of these changes are already underway as utilities incorporate green spaces to naturally clean water before it is drained from cities and into waterways. He also credited innovations in “real-time” management that allow operators to wirelessly direct water flows through remote-controlled pumps and valves to “prevent flash floods before they happen.”
Bartos said cities should start by studying the current system.
“We don’t know how much water is flowing through these systems at any given time, and we don’t know if the actual stormwater flows match the digital models used to design these systems,” Bartos said in an email. . “As such, it is difficult to predict how real-world stormwater systems will react to current storm events, let alone future events.”
Cover photo: Corina Ley, 18, ventures with the dog Capri into the flooded Album Park on Monday. The park remained under several feet of water due to a storm a day earlier. (Danielle Prokop / El Paso Matters)