Delmarva Map Series

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This series of maps covers the Delmarva Peninsula and its unique geography, as compared to the rest of the northeastern and mid-Atlantic United States, and is inspired by the idea of elevation and relief maps. However, because the Delmarva Peninsula is very flat, elevation and relief maps of the area would not be very interesting. In examining Delaware's GIS data, specifically, I found that the wetlands layer could yield a beautiful representation of the state, so that was used as the basis of these maps.

These maps were made public on the sixth anniversary of when I moved to Delaware.

Data Sources and Data Management

These maps were developed using GIS data from various sources, including:

The datasets required numerous adjustments to ensure consistency in data representation, as each state had slightly different schemas (data layouts). Additionally, rendering datasets from five separate states, for each state-derived collection, required considerable processing power. Thus, the state-derived datasets were combined into one for each type (e.g., roadways, municipalities), keeping the data necessary for representation in the map (e.g., municipalities would require the name, state, and population, as population determined the formatting of the label). The Waterway Names dataset had its geometry "simplified" with a tolerance of 10 meters, to reduce the necessary computing power to render it. All large datasets were clipped to an area deemed appropriate, bounded approximately as follows: Harrisburg PA in the northwest, Asbury Park NJ in the northeast, Kitty Hawk NC in the southeast, and Rocky Mount NC in the southwest.

I am aware that there could be some improvements made to the data representation on these maps. I'm particularly concerned with the representation of bannered routes (e.g., US-13 Alternate, MD-404 Business), as each state has a slightly different way of handling these types of routes. This leads to inconsistencies in representation between states. For example, the US-13 Business routes in Delaware are represented as "13B" (see Bridgeville), but in Maryland they are simply "13" (see Salisbury). Also note the sharp difference in color used to represent the ocean in any area with Atlantic coastline. As the National Wetlands Inventory data was downloaded by state, it cuts off fairly close to each state's eastern land boundary.

Technology Used

All maps were developed using QGIS 3.24, running on Fedora 36. Three computers were used to develop the maps, listed below:

The Maps

All maps were rendered in JPEG format, to reduce file size. The maps are rendered in a high resolution, with large-scale maps at 6600x10200 resolution (approximately 12 MB each). County and local maps are rendered at 3300x5100 resolution (approximately 2-3 MB each). Each map is listed below, in Delaware-to-Maryland-to-Virginia, north-to-south order.