Cameron Run & Huntington Flooding: A Recurring NoVA Risk

Of all the places that flood in Northern Virginia, few carry as clear a story as Cameron Run and the Huntington community that sits in its floodplain. This is not a tidal story like Old Town Alexandria a mile to the north, nor a slow riverine rise like the outer counties. It is the story of an urban watershed: a wide, heavily paved drainage area that funnels rain into a single channel which can climb from placid to dangerous within an hour or two. Understanding why this corridor floods — and what has been done about it — is a case study in how Northern Virginia’s geography concentrates flood risk.

• Old Town Alexandria
• Cameron Run
• Bloomingdale
• Anacostia (Wards 7–8)
• Ellicott City

What and where is Cameron Run?

Cameron Run is the main stem that carries the drainage of a large, densely developed slice of Fairfax County and the City of Alexandria down toward the tidal Potomac, joining the river near the Woodrow Wilson Bridge. It is fed by two major tributaries that residents of the area will recognize: Holmes Run, which drains parts of inner Fairfax and Alexandria from the west, and Backlick Run, which drains the Springfield and Annandale side from the south. By the time these streams combine into Cameron Run, they are collecting runoff from a substantial urban catchment.

That urban character is the whole point. In a forested or rural watershed, rain soaks into the ground and reaches the stream slowly, spreading the rise over many hours. In Cameron Run’s watershed, much of the land is roof, road, and parking lot, so rain runs off almost immediately and arrives at the channel fast. The result is a flashy stream — one that responds to intense rain within an hour or two rather than over a day. That is exactly the behavior that makes urban flash flooding so dangerous: the warning window is short.

Why this corridor floods so readily

Three factors stack up to make the Cameron Run corridor one of Northern Virginia’s flashiest:

• Impervious surface. Decades of development have paved over the land that once absorbed rain, so a far greater share of each storm becomes immediate runoff.
• Converging tributaries. Holmes Run and Backlick Run deliver their flood peaks into the same main stem, and when those peaks coincide, Cameron Run carries the combined load.
• Low, flat floodplain at the bottom. Where Cameron Run approaches the Potomac, the valley flattens and broadens, and the Huntington neighborhood occupies low ground squarely in that floodplain.

This is the mechanism our DMV flood geography overview describes as flash flooding in urban watersheds — distinct from the tidal flooding that defines Old Town Alexandria and the combined-sewer flooding seen in older parts of DC. Knowing which mechanism threatens a given block tells you how much warning to expect, and along Cameron Run the honest answer is: not much.

The June 2006 flood at Huntington

The corridor’s defining event came in late June 2006, when an extended period of heavy rain across the watershed sent Cameron Run over its banks. The Huntington community — a neighborhood of homes just south of Old Town Alexandria, sitting low in the floodplain — was inundated. Water rose into homes, displaced families, and caused extensive damage to a community that had flooded before but not at that scale in recent memory.

The 2006 flood was a turning point. It demonstrated that the existing channel and drainage could not protect Huntington from a severe event, and it galvanized Fairfax County to act. What followed was one of the most significant flood-mitigation projects in Northern Virginia.

The Huntington levee and pump station

In response to the 2006 flood, Fairfax County designed and built a levee and stormwater pump station to protect the Huntington community. The system works on two fronts. The levee is an earthen barrier that holds back high water on Cameron Run, keeping the swollen channel from spilling into the neighborhood. But a levee creates a second problem: rain that falls behind the levee, inside the protected area, has nowhere to drain when the river outside is high. That is what the pump station solves — it lifts the interior stormwater up and over the levee and into Cameron Run, so the protected neighborhood does not fill up from the inside.

It is a substantial piece of public infrastructure, and it has materially reduced the flood risk to Huntington. But it is important to state the limit plainly.

For the official picture of how Fairfax County maps and manages this corridor — including the stormwater program behind the levee — see our Fairfax County flood resources guide and the county’s own stormwater management program.

The Holmes Run and Backlick Run connection

It is easy to think of “Cameron Run flooding” as a single-channel problem, but the levee at the bottom of the system only addresses the last stretch. The flood risk along the corridor is really the sum of what happens upstream on Holmes Run and Backlick Run. Holmes Run flows through Alexandria and inner Fairfax, passing parks and channelized reaches where it can rise sharply in a downpour; Backlick Run drains the Springfield-Annandale side. Each tributary has its own flood-prone pockets well above Huntington, and a property along either branch faces flash-flood risk independent of the levee that protects the community downstream. That is the central caution of an urban watershed: the engineered fix protects a specific place, while the underlying flashiness affects the whole drainage network. Anyone living along the upper tributaries should check their own address rather than assume the downstream infrastructure covers them.

Watching the watershed in real time

Because Cameron Run rises so quickly, real-time data is especially valuable here. The USGS Water Data network for Virginia publishes near-real-time gauge readings for streams across the state, and gauges on Cameron Run and its tributaries show just how fast levels can change during a storm. Pairing an upstream gauge with the NWS Baltimore/Washington forecast gives residents the earliest possible read on an approaching flood — and the same gauge data feeds the official flood forecasts.

The practical takeaway is the same as the warning above: in a flashy watershed, the gauges and the forecast are not a substitute for early action. If a strong storm is training over the watershed, the safe assumption is that Cameron Run will respond quickly. Our storm season preparation guide covers how to get ready before a season of these storms, and the DMV flood resources hub lists the alert sign-ups that deliver the warnings.

Huntington in the wider Northern Virginia picture

Cameron Run and Huntington are one chapter in a larger regional story, and the comparison with their neighbors sharpens the lesson. A mile north, Old Town Alexandria floods from the tidal Potomac rather than from rain — its water comes from the river backing up at high tide or under storm surge, which gives hours of forecast warning through tide tables and coastal advisories. Cameron Run is the opposite case: its water comes from the sky, arrives within an hour or two, and offers little forecast lead time. To the west and north, Arlington and inner Fairfax are threaded with steep stream valleys — Four Mile Run, Pimmit Run, and others — that flash-flood in their own right. Each of these is mapped and explained in our Northern Virginia flood-prone areas guide. What unites them is that none of them flood randomly: each follows the water, the slope, and the pavement in a predictable way.

Check your own risk along the corridor

What it means for flood insurance

Living in or near the Cameron Run floodplain has a concrete consequence: flood insurance. Standard homeowners policies do not cover flood damage, and a home in a mapped high-risk zone with a federally backed mortgage will generally be required to carry a flood policy. The levee complicates the picture rather than removing it — being behind protective infrastructure can change a property’s mapped status, but it does not change the underlying fact that the corridor has flooded and could again. Our guide to flood maps, zones, and insurance explains the zone letters and the National Flood Insurance Program, and our flood zones and maps guide walks through reading the maps themselves.

Putting it together

Cameron Run and Huntington show how a single watershed concentrates flood risk: pave a large catchment, funnel it into one channel, settle a community in the low floodplain at the bottom, and you get a place that floods fast and floods again. The 2006 disaster and the levee and pump station that followed are the visible markers of that story — proof that the risk is real and that it has been engineered down, but not away. For any address along the corridor, the reputation of the neighborhood is no substitute for the map: confirm your specific risk at the FEMA Flood Map Service Center and Fairfax County’s tools, watch the National Weather Service when a storm is on the way, and use the Fairfax County flood resources and Northern Virginia flood-prone areas guides for the full local and regional picture.