This is our fourth post of a map of… something in DC. Our last map was a challenge for most of our readers. Last time, the map showed the number of times each station had appeared in the other Greater Greater Washington game, WhichWMATA. Can you guess what this one is showing? If you need clues, there are five after the jump!

All maps made by the author using data from the District government’s open data portal.

Here are five clues for what this map is showing:

     
  1. The map accounts for five possible scenarios.  
  2. A recent weather forecast originally warned a major, named weather system that could affect our region. This map shows what might happen if the forecasts are right.  
  3. More specifically, many meteorologists anticipate the forecasted storm to have an impact the likes of which this region had not seen since Hurricane Agnes in 1972.  
  4. Because of DC’s location below the fall line, it isn’t always the rain we should be worried about with these particular storms.  
  5. A series of levies and other infrastructure should some areas from being colored in if there is a storm.

A closer look at three sections of the map:

Answer update: The map shows the buildings most likely to be inundated by a hurricane storm surge event. Buildings shaded light blue would likely flood during a Category 1 hurricane while buildings shaded in dark blue would likely flood during a Category 5 hurricane. Flooding is cumulative, so, a Category 3 hurricane would also flood buildings impacted by Category 1 and 2 hurricanes.

Fortunately, Hurricane Joaquin did not make landfall. You may have seen the installation of removable flood barriers around town, particularly around the Georgetown waterfront, in preparation for a potential flood event.

Scott Kaiser is an environmental planner specializing in urban watershed management and building climate resilient communities around the world. He has a strong interest in the application of geospatial technologies to better inform resource management decisions and is an all-around urban planning nerd.