Photo: Nathan Anderson / Unsplash

Two Floods in Twenty-Two Months

Brittany O'Connell was working the dinner shift at a restaurant on lower Main Street when the water came through the glass. It was July 30, 2016, a Saturday evening, and the rain had been falling hard for less than two hours when she looked down from the second floor and watched the ground floor fill. The windows gave first. Then the door burst inward. Water — brown, fast, carrying furniture and trash cans and parts of other buildings — flooded through the dining room at a velocity that turned tables into projectiles. She and her coworkers evacuated upstairs. Below them, Main Street had become a river.

Ellicott City sits in a valley at the confluence of three streams — the Hudson Branch, the Tiber Branch, and New Cut Branch — all of which drain through the historic district and empty into the Patapsco River. The town was founded in 1772 as a milling settlement, its stone and brick buildings climbing the hillsides above the water. In 1830, it became the first terminus of the Baltimore & Ohio Railroad outside of Baltimore. For two and a half centuries, the topography that made the mills profitable also made the town flood-prone. There are records of catastrophic flooding in 1868, when the Patapsco rose twenty-one feet and killed forty-three people. The 1972 flood from Hurricane Agnes was the worst in a century. But what happened on that Saturday in 2016 was different. Six and a half inches of rain fell in three hours. The USGS classified it as a storm with a probability of occurring once in a thousand years. Two people died — Jessica Watsula and Joseph Blevins, both swept into the Patapsco when their vehicles were overtaken by the current. Hundreds of vehicles were washed downstream. The town's iconic clock was ripped off its post and found in the river mud.

The clock was restored and returned to its pedestal in 2017. O'Connell and other Main Street workers came back to their restaurants, their boutiques, their antique shops. Howard County began planning stormwater retention ponds. Federal money arrived from FEMA. Recovery was slow and bureaucratic but it was happening. Shop owners painted new signs. A restaurant owner named Angie Tersiguel, whose French Country Restaurant had survived both floods, kept the doors open, kept the tables set, kept showing up.

Then, on May 27, 2018 — twenty-two months after the first flood — it happened again. Over eight inches of rain fell in two hours. The restored clock vanished again. Buildings that had just been repaired collapsed. National Guardsman Eddison Hermond, helping a local business owner escape the rising water, was swept into the Patapsco and drowned. His body was recovered two days later. The 2018 flood was classified as a two-hundred-year storm by some meteorologists and a thousand-year storm by others. Two thousand-year storms in under two years.

O'Connell remembers standing on a second-floor balcony watching the water rise past the same windows, past the same threshold, through the same dining room. The same flood. The same town. Twenty-two months apart.

Cool. Now explain who pays.

Boring Through Granite

Ellicott City's flood vulnerability is not a mystery. It is a function of its topography, its hydrology, and the impervious surface coverage that has expanded across the watershed as Howard County urbanized over the past fifty years. The three streams that drain through the historic district collect rainfall from a catchment area of roughly twenty square miles. As development upstream replaced forest and farmland with parking lots, rooftops, and roads, the volume and velocity of stormwater reaching Main Street during intense rainfall events increased dramatically. The streams that once rose slowly now flash. The historic buildings, many of them constructed directly over or adjacent to the streams, sit in the path of water that has nowhere else to go.

The 2016 flood cost an estimated $67 million in economic losses and eliminated 151 jobs on Main Street. The 2018 flood, arriving before recovery was complete, compounded the damage. Howard County Executive Allan Kittleman signed legislation authorizing the demolition of thirteen historic buildings in the floodplain — including the Phoenix Emporium and Discoveries, two of the most recognizable structures on Main Street — at a cost of $50 million. The demolitions required permits from the Historic Preservation Commission, the Maryland Department of the Environment, and the U.S. Army Corps of Engineers, each of which raised concerns about altering the character of a district on the National Register of Historic Places.

Calvin Ball took office as Howard County Executive in December 2018, weeks after the second flood. Within days, he announced the Ellicott City Safe and Sound plan — a comprehensive flood mitigation strategy built around seven major infrastructure projects. The centerpiece: an 18-foot-diameter tunnel, approximately one mile long, bored through the solid granite bedrock that underlies the historic district. The Extended North Tunnel, as it was formally named, would intercept stormwater from the West End of Ellicott City and divert it underground, directly to the Patapsco River. Its design capacity: 26,000 gallons per second — roughly the equivalent of filling a residential swimming pool every second during a major storm.

The machine excavating the tunnel is a tunnel boring machine — a 300-foot-long piece of industrial equipment that chews through granite at depths up to 100 feet below the surface. In a public naming contest that drew nearly 800 votes, Howard County residents christened it Rocky.

$300 million. For a town with one Main Street.

That number requires context. Ellicott City is an unincorporated community within Howard County — one of the wealthiest counties in the United States, with a median household income exceeding $125,000. The county has the tax base, the bond capacity, and the political infrastructure to assemble a $300 million funding package using creative layering of federal loans, state grants, and local appropriations. The question embedded in the Safe and Sound plan is not whether Ellicott City can afford it. The question is what happens to the towns that cannot.

The funding architecture reveals the mechanism. Howard County leveraged a $75 million federal WIFIA loan — a competitive financing instrument from the EPA that offers below-market interest rates and saved the county an estimated $13 million in borrowing costs. It layered on $52 million in state revolving fund loans, $20 million from Maryland's Resilient Maryland Revolving Loan Fund, and $58 million in direct grants. The $100 million-plus in local funding came from county bonds backed by one of the strongest tax bases in the region. This is not a funding model that can be replicated in Westernport, Maryland — a town in Allegany County that experienced devastating flash floods in May 2025 and has neither the bond capacity nor the federal relationships to assemble a comparable package.

Notice what Ellicott City has that most flood-prone towns don't: a county executive who can mobilize federal and state relationships, a tax base that supports $100 million in local bonds, and proximity to both Annapolis and Washington that makes it a convenient demonstration project for state and federal resilience programs. The Safe and Sound plan works because Howard County is wealthy enough, politically connected enough, and visible enough to make it work. The infrastructure is real. The engineering is sound. The TBM named Rocky is, right now, boring through granite a hundred feet below Main Street. But the model is not transferable. It is exceptional.

The contrast with other flood-prone historic towns is stark. Westernport, Maryland — population roughly 1,800, in Allegany County — experienced devastating flash floods in May 2025 when over five inches of rain fell in a single event. Governor Moore declared a state of emergency. But Westernport does not have a $300 million funding stack. It does not have a county executive assembling WIFIA loans. Its county's median income is less than half of Howard County's. The state's Resilient Maryland Revolving Loan Fund, which contributed $20 million to Ellicott City's plan, exists in part because of the advocacy of legislators representing Howard County — the same legislators who ensured their own district was the fund's first beneficiary. The institutional machinery that builds resilience in one place is often funded by the political capital generated in that same place. Westernport has neither the machinery nor the capital.

The Resilience Premium

The pattern Ellicott City reveals is not about flooding. It is about who gets to adapt.

The Fourth National Climate Assessment, published in 2018, warned that "without significant reductions in greenhouse gas emissions and other adaptation strategies, many communities will face increasing challenges from flooding and other climate-related risks." The assessment noted that infrastructure investment is the primary mechanism by which communities reduce climate vulnerability, and that the capacity to invest is highly uneven across American municipalities. Wealthier communities with stronger tax bases, better access to federal financing, and greater institutional capacity are systematically better positioned to adapt.

This is not a new insight. Urban resilience scholars have documented what some call a "resilience premium" — the tendency for adaptation investment to concentrate in communities that already have economic and political resources, while the communities most vulnerable to climate impacts are least able to fund protective infrastructure. A 2021 study in Nature Climate Change found that federal disaster mitigation spending in the United States is disproportionately directed toward higher-income communities, in part because grant applications require technical capacity that underfunded local governments often lack.

Ellicott City is already being held up as a national model. Maryland State Delegate Courtney Watson has said she hopes the Safe and Sound plan can "model and assist other jurisdictions who are facing the same type of problems." Governor Wes Moore, at a March 2025 Board of Public Works meeting, framed the North Tunnel as evidence that "Maryland is stepping up" even as federal grants face uncertainty. The rhetoric of replicability is encouraging. The fiscal reality is less so.

The EPA's WIFIA program — the instrument that provided Ellicott City's $75 million loan — is a competitive financing mechanism that evaluates applicants on creditworthiness and project readiness. Communities with well-developed engineering plans and strong credit ratings get access. Communities with aging infrastructure, shrinking populations, and limited planning staff do not. The Safe and Sound plan's funding stack — federal WIFIA loan, state revolving fund, state resilience fund, county bonds — requires the applicant to already have the institutional capacity to pursue each funding source simultaneously. That is a feature of wealthy, well-governed jurisdictions. It is not a feature of the small, flood-prone towns that need adaptation investment most urgently.

Consider the contrast with a prior IN-KluSo signal. In Lake Charles, Louisiana, Hurricane Laura damaged 50,000 housing units in 2020. Five years later, 1,817 federal recovery grants had been issued — a documentation-driven filter that systematically excluded the poorest and least-documented residents. The mechanism is the same in Ellicott City, inverted. Instead of being filtered out of recovery by documentation requirements, Howard County is filtered into adaptation funding by institutional capacity. Both mechanisms produce the same structural outcome: resilience accrues to those who already have it.

Rocky is boring through granite right now, one hundred feet below the shops and restaurants of historic Main Street. It will emerge at the Patapsco River in 2027, and when the next thousand-year storm hits — because the climate data suggests there will be a next one — the tunnel will swallow 26,000 gallons per second and carry them safely underground. It is an extraordinary piece of engineering. It is also a $300 million answer that only a $125,000-median-income county can write.

The pattern isn't the flood. The pattern is who gets the tunnel.

Alternative Explanations