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Fingers in the Dyke

Fairfax County organizes Hurricane Workshop for Mount Vernon residents.

As the wind and rain of Hurricane Katrina thrashed past passed Mount Vernon, a silent swale of water ten feet high was rolling steadily up the Potomac. On September 19, 2003, hours after the storm surge spilled across the banks of the river, over the George Washington Parkway and into Belle View and New Alexandria, Fairfax County Fire and Rescue workers were cruising through the flooded neighborhoods in their inflatable motorboats, according to Captain James Chinn, Marine Operations Manager. They were looking for residents who had not evacuated.

Though only a few inches deep in places, the water was a danger source. It had extinguished pilot lights in basements and was absorbing streams of natural gas. It was dissolving fertilizers and absorbing poisons. It had lifted the lids off manholes, concealing tunnels of streaming water that could suck down a would-be rescuer after one misstep. The men in the boats noted that the windows of many houses were still cozily illuminated. “That tells us that the electricity is on in those areas,” Chinn said, “and the water is energized.”

Chinn was describing why it is much easier for people to leave an area when the evacuation notice goes out, rather than after the disaster arrives. He was one of the speakers at Fairfax County’s June 3 Hurricane Awareness Workshop, hosted by Mount Vernon United Methodist Church. Representatives of the U.S. Army Corps of Engineers, the National Weather Service and the county’s emergency planning and response personnel gave an overview of what happened in Isabel, how the county reacted and what it will do when the next hurricane hits.

DAVID MANNING of the National Weather Service described the weather events that surround a hurricane. He said that wind, wave action and barometric pressure are all factors that effect the water that crests around a hurricane. This water travels more slowly than the storm itself, and for coastal or riparian communities, it can be far more destructive, particularly if the tide is high. The height of the storm tide (the height of the surge plus the height of the tide when the surge reaches land) is “the magic question” for meteorologists trying to forecast the damage a hurricane will create, said Manning.

New studies suggest that higher storm surges than previously thought may be able to reach Alexandria and D.C. Manning said that in one “very, very rare scenario, an extremely rare scenario, a unique storm,” a 15 to 20 foot storm surge could break over D.C. “There’s a lot of very important structures that would be very wet,” Manning said. “[But] it does not take much at all to get Old Town wet.” A wave of even one and a half feet could spill onto King Street. Manning said this susceptibility to flooding is partly because the ocean level has risen since Alexandria was founded over 250 years ago.

CRAIG THOMAS, of the Army Corps of Engineers, unveiled the results of a complex computer model the Corps created at the request of the county. It predicted what storm surge levels were possible from a hurricane, their likelihood, the impact on the South Alexandria area, and possible safeguards that could be put into place.

The study revealed that in this area, the statistical likelihood of a 9.5 foot surge the size of Isabel’s is once every 50 years. It had previously been thought to be 100 years.

Thomas said the county will follow the study with a more thorough look at how each building in the area could be effected, then it will create an action plan to minimize damage from another flood.

Thomas said three safeguards were worth the county’s consideration: acquisition, levees and floodwalls and flood-proofing. Acquisition would simply entail the county, possibly with the Federal Emergency Management Agency (FEMA), buying up properties that are at risk of flooding and putting them out of commission.

Thomas said levees and/or floodwalls would provide complete protection, and showed a map of a floodwall running down the west side of the George Washington Parkway. But there are serious drawbacks to this approach. A five foot levee requires a base with a width of eighty feet, said Thomas. Floodwalls are more complex to design, and both would be expensive, take up property, block views of the Potomac, and have environmental impacts on sensitive areas such as Dyke Marsh.

Dry flood-proofing requires sealing up buildings with paint and barriers. But this can only be done up to a height of three feet, any more and the hydrostatic pressure of the water outside could crush the building. This is also an expensive option. Wet flood-proofing is more feasible. This entails raising electrical systems out of the flood zone and building vents into the walls that allow water to fill a pre-designated low-lying area, like the basement. This is a cheaper option, but requires advance notice of floods so that home-owners can empty out the rooms of their house that will fill with toxic water.

GERALD JASKULSKI, an assistant coordinator with the Fairfax Office of Emergency Management said the county had learned from Isabel. “When something happens and it doesn’t change behaviors or modify plans, that’s the tragedy,” he said. Fairfax now boasts an emergency response system with built-in redundancies. If the power goes out and a person can no longer receive emails from “Riverwatch” the county’s flooding list-serv, residents can still receive automated reverse-911 calls on their corded telephones. If all they have is cordless (which, unlike old-fashioned models, don’t operate without electricity) they can still hear reports over the radio, coordinated from the county’s new emergency operations center. The Community Emergency Alert Network (CEAN) can deliver messages to email, cell phones, text pagers, satellite phones and wireless PDA’s. And if all else fails, the police and emergency workers will go knocking on doors.

But “the biggest thing,” Jaskulski said, “Get your family, friends prepared ... These things are going to happen always. They never go away.” He advised people to always have an emergency kit packed. “Have a party every six months. Drink your water. Eat your candy bars. Exchange our tooth brushes. Then repack it.”

Chin said that people’s emergency kits should be small. He referenced the small rescue boat parked in the church lot and said, “The issue is when people show up at the door and they’ve got suitcases … the main focus is lives and if we get those out we’re not going to worry about the suitcases.”

THERE WERE about fifteen people at the meeting. When asked why he was there, Stephen Snell replied, “I survived Isabel … I did not evacuate. I stayed in Belle View [Apartments] and I did everything you should not do … I was totally naïve.” On the night of the hurricane, Snell heard car horns and saw flashing headlights in the parking lot. Thinking it was his neighbors, he rushed out of his third floor condominium into the darkness. He found himself standing in six inches of water, surrounded by empty, short-circuiting cars and dumpsters “floating around like rubber ducks.”

Snell rushed from the flood outside into his flooded basement, realizing only later that if the electrical systems had been affected, “I would have been toast.” He avoided electrocution, but not the backed-up sewage that contaminated the water. He spent the next two weeks in a hotel.

Inspired by his experience, Snell created an emergency manual for residents of Belle View. He recommends that everyone in a flood plain get a National Oceanic and Atmospheric Administration (NOAA) radio and keep it plugged in, subscribe to the Riverwatch list-serv and “if you hear ‘evacuation,’ get out. Debating whether it’s voluntary or mandatory is like debating how many angels can fit on the head of a pin.”

Snell praised the county for doing a “remarkable job” learning from Isabel. “I have complete faith the county is well-prepared now,” he added.