The drawings are spread across her desk—cross-sections, hydraulic calculations, the usual design for replacing a washed-out culvert on a town road in Woodbury, Connecticut. She's got NOAA Atlas 14 open on her computer. The numbers say 7.2 inches in 24 hours for the hundred-year storm.
She's also got the rainfall data from last August open in another window. 14.83 inches fell near Oxford, twenty miles south. The culvert she's replacing washed out that night, along with half the road. Cost the town $380,000 in emergency repairs.
She looks at both screens. Then she designs to the 7.2.
Atlas 14 is the law. Every culvert size, every storm drain capacity, every flood elevation in America comes from its precipitation frequency estimates. The atlas gathers data from the past 30 years to predict future storms. The Northeast volume came out in 2015. Some volumes are over 20 years old.
The atlas tells engineers to design for weather that doesn't exist anymore. Engineers, being licensed professionals who follow codes, design for weather that doesn't exist anymore. Then the actual weather shows up.
By late July 2025, the National Weather Service had issued almost 4,000 flash flood warnings —more than any year since they started counting in 1986. Vermont's Northeast Kingdom saw the road to Sutton wash out again in July after the town had already spent over a million dollars on previous flood repairs. Each storm tests infrastructure designed using numbers from before the storms started breaking records.
The engineer knows this. She runs the calculations. She sees what's actually falling from the sky versus what Atlas 14 says should fall. The gap keeps getting wider.
"The latest data demonstrates that the past 30 years of rainfall does not represent the extreme weather events of today—or tomorrow," Shirley Clark, who heads Penn State Harrisburg's Urban Stormwater Infrastructure Research Group, told Civil Engineering Source.
At the selectboard meeting, the engineer presents her design. The drawings show a 48-inch culvert, properly sized per Atlas 14, with standard erosion protection. The board reviews the $340,000 estimate.
"Will this one survive the next flood?" the selectman asks.
She could tell them the truth. She could show them last August's rainfall data, explain that Atlas 14 is obsolete, that the new culvert will probably wash out in five years just like the last one. She could recommend oversizing it by 50 percent, adding $120,000 to the cost.
She says: "It meets all applicable codes and standards."
The selectman nods. The board approves. The engineer goes home.
Engineers are supposed to exceed outdated codes to meet ethical obligations, but can't get insurance for exceeding codes, and might be liable for not exceeding codes if infrastructure fails.
The professional engineering societies know what's happening. The National Society of Professional Engineers offers a course on design liability in a changing climate. The course states that codes might not be adequate anymore, that engineers might need to exceed them to meet their ethical obligations. It also warns that contracts with language about "best" or "highest" standard of care can expand liability beyond what's insurable.
An editorial in Structure Magazine put it plainly: an engineer who designs only to meet code may not be designing to what clients, regulators, or courts might consider reasonable best practice under changed climate conditions.
The fix sits in limbo. Atlas 15 was supposed to replace the outdated rainfall data with modernized estimates including future climate projections. NOAA got congressional funding through the 2021 Bipartisan Infrastructure Law. The new atlas would forecast in two parts: recent observations accounting for altered weather patterns, and increasingly severe rainfall expected ahead.
It was scheduled to debut in fall 2025. As of June, NOAA wasn't answering questions about the project's status. Employees had resigned. Concerns were mounting that it might be shelved due to budget cuts.
"Data is something that needs to be updated continuously," Lisa Foster, Pinellas County's Floodplain Coordinator, said after three major hurricanes in 2024. "We absolutely need it. Local governments can't do this level of modeling."
Local governments are expected to keep building infrastructure anyway, using the old numbers.
Some states are trying to patch the problem. New Jersey updated its stormwater regulations in 2023 after Hurricane Ida, requiring major developments to handle current and anticipated future storm events. Connecticut updated its manual in 2024. They still rely on Atlas 14's outdated estimates for the actual numbers.
The infrastructure keeps failing. Plainfield, New Jersey's fire department reported that intense rainfall dropped over 7 inches in less than five hours last July, overwhelming stormwater infrastructure designed for less than half that. The engineers who designed that infrastructure followed the standards. The standards were just wrong.
Back at her desk, the engineer in Woodbury has another project. A different road, a different culvert that washed out last summer. She opens Atlas 14. She reads the numbers she knows are wrong. She designs the replacement that will probably wash out in five years.
She has to. The code requires Atlas 14. The insurance requires following the code. The license requires following the code. The town needs a culvert.
In five years, when it washes out, she'll design another one. Also to Atlas 14. Also wrong. She knows this. The selectboard will ask again if this one will survive. She'll give the same answer: it meets all applicable codes and standards.
The maps are wrong. Everyone knows they're wrong. The work continues.
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New York City's century-old system: NYC's stormwater infrastructure is designed for a five-year storm based on 1903-1950 data, equivalent to 1.75 inches per hour, while the city received over 2 inches in an hour last July.
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Connecticut's culvert mapping requirement: Governor Lamont's 2025 legislative proposal includes requiring municipalities to acquire the geolocation of all culverts as part of strengthening resilience against extreme weather.
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The insurance industry's position: Professional liability insurers routinely defend engineers against claims that more robust designs would have better accounted for severe weather, even as standard-of-care provisions in contracts create greater risk.
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Flash flood warning records: The National Weather Service issued nearly 100 flash flood warnings in a single July day in 2025, the most warnings ever issued by NWS on any July day since comparable records began in 1986.