Stuck in the Middle With (897,933 of) You

Census Bureau Director Robert Groves was out in the tiny village of Plato, Missouri, yesterday to unveil a National Geodetic Survey disc commemorating Plato as the new national center of population.

The Census Bureau calculates the center of population after each census as "the place where an imaginary, flat, weightless and rigid map of the United States would balance perfectly if all residents were of identical weight." The center of population has moved slowly west and south from Kent County, Maryland, in 1790 to Missouri.

The Census Bureau also calculates the center of population for each state. In 2010, the center of population for the 897,934 of us counted in Delaware was northeast of Smyrna, along Route 9.

It's Census Time!

I was out cutting the grass this morning. It was my first run at the lawn this year. The grass was thick. While I was working on the front lawn, I noticed a car driving slowly around the neighborhood, stopping in front of each house for a minute or so while the driver entered data on a small handheld computer.

He noticed my watching him and so stopped, stepped out, and let me know he is with the Census Bureau. I was not surprised; it was what I thought he was doing. I explained and we had a nice short chat.

As one of my responsibilities as a Delaware state employee, I serve as the Governor's Liaison for the 2010 Census in Delaware. I spent Friday of last week at the Regional Census Office in Philadelphia, discussing plans for the census with staff there and with state folks from Maryland, DC, Pennsylvania and New Jersey. The Bureau let us know that address canvassing was about to start and that Delaware is one of the places where it is starting first in our region.

Address canvassing is a huge job and the first major step in the decennial census. Around 140,000 temporary census workers will fan out across the whole of the US and, block by block, check more than 145 million addresses. The census itself is a mail-based survey; everyone gets a census form in the mail (though there are non-mail ways to get information from those without addresses and such). If the Census Bureau does not have a comprehensive and accurate database of addresses, the census won't work.

So the folks out there now, checking addresses, are vital to the census, which is a key to our democracy. Be kind to them.

Meanwhile, when I broke for lunch and checked the web, I found a comment by Nancy Willing on Brian Shields' post about Google Streetview having recently added imagery of Seaford:

I think the Google Street lady stopped in front of my house yesterday. She pulled right up in front of my house, jumped out and (very energetically for her apparent age) and stood briefly in front of each house in the cul-de-sac, furiously writing something in a notebook before driving away.

While I did leave a correction comment (can't help myself), Nancy was not too far off the truth.

One of the important things that the address canvassers are doing is making sure that the addresses that the Census Bureau has are coded to the correct census blocks. and they are making sure that those blocks are defined by streets that are actually there (after all, things change). This information becomes part of the Bureau's Topologically Integrated Geographic Encoding and Referencing system -- known as TIGER.

TIGER is often referred to as a precursor to Geographic Information Systems (GIS) and the Bureau's TIGER data was for many years the base-map for most GIS applications in the US. Google Maps, and Google Earth, are the most recent outgrowth of GIS activities; they provide a common base map for access to a wide range of public geospatial data.

So the work of the address canvassers can be directly related to Google Maps, streetview and applications like that. In a way, that was "the Google Street lady" in front of Nancy's house.

More Disclosure: GIS and geospatial data are another part of my state job; I am State GIS Data Coordinator for Delaware.

Rather Than Re-Typing the Whole Thing Here...

Allow me to direct your attention to a post I wrote this week for The NSGIC Blog. The post, Boundaries Matter, is about the Delaware vs New Jersey boundary kerfuffle and a somewhat similar boundary dispute between Georgia and Tennessee.

I'm a member of NSGIC -- The National States Geographic Information Council -- and one of the authors on that group's blog. We try to highlight stories and issues of interest to the people in the various states who create and share geospatial data.

Stories about boundaries -- state boundaries -- are definitely of interest.

Reaching the Edge of the Place

Last night I drove to the edge of the continent and had to turn around and head back inland.

I was driving in to Rehoboth Beach to pick up Colleen, who had attended a show at the Rehoboth Summer Children's' Theatre. Rather than try to make what can be a difficult left from Rehoboth Avenue, the resort's main drag, I followed that road to its end at the boardwalk and made the circle around the Rehoboth Bandstand.


View Larger Map

It's a route I've taken hundreds of times in the last twenty years. For some reason, though, last night it felt clearly like I was just reaching the end of the continental US and had to turn around because I could go no farther.

It was startling to see that spot in a different clarity for a moment.

A Road Runs Through It

There's a new study published in the journal Science that looks at roadless space in the continental United States. It finds the remarkable fact that no point in the continental US is more than 22 miles from some sort of road.

The Science magazine website is by subscription, but the abstract of the study, Roadless Space of the Conterminous United States, notes that the authors have created a new way to measure roadlessness:

We introduce a metric, roadless volume (RV), which is derived from the calculated distance to the nearest road. RV is useful and integrable over scales ranging from local to national. The 2.1 million cubic kilometers of RV in the conterminous United States are distributed with extreme inhomogeneity among its counties.

The map image above shows RV by County. The scale ranges from high RV areas, shown in blue, where there are more areas without roads, to low RV areas, in red, where there are more roads.

Discovery News presents a longer overview of the study (Roadless Space Uneven Across U.S.) which discusses the relationship between this new measure of roadlessness and habitat fragmentation, and notes that the study found that, in some areas, we seem to build roads in the wrong places:

And when the scientists compared the roadless space with the number of people in a given area, they sometimes found a mismatch: that is, too many roads for too few people.

The study's abstract, by the way, offers a lovely example of scientific obfuscation. That poetic phrase "distributed with extreme inhomogeneity" means, I think, "not in any regular way that this highly trained scientist can see."

An Apparition

For some, its the Virgin Mary appearing in French Toast. For me, it's the state of Delaware appearing in a puddle. I'll take what I can get.

Delaware's Unique Border

A blog called Strange Maps has started looking at Delaware's rather unique border. There are two posts, so far. It's interesting to see the various oddities of my state's boundary discussed by an "outsider." I advise bringing along a pinch of salt to take when you read the Strange Maps posts, there are a few very minor mistakes.

My day-job involves mapping, geospatial data, and working with things like the border in Geographic Information Systems (GIS) software. I also work closely with my friend Sandy Schenck of the Delaware Geological Survey. Sandy's first job, many years ago, was finding and maintaining the 179 stone boundary monuments that mark the Delaware border. He wrote a wonderful monograph on the boundary. That's my authoritative source on these issues.

The images I've used in this post, by the way, were created using the Delaware Data Mapping and Integration Lab -- The DataMIL -- which provides a digital base map of Delaware, replacing the old paper topographic map series with a more frequently updated, web-based, topo map.

The first Strange Maps post is Where Delaware Met Pennsylvania (1): the Twelve Mile Circle. It looks at the odd border issues caused by the decree in colonial times that a circle with a radius of 12 miles, centered on the town of New Castle, be used as a boundary.

Strange Maps describes this as "the only US boundary that’s a true arc." That's sort-of true; it's the only one that is circular. It is not, in fact, a true arc. The chain used to measure the 12 miles and so to survey that part of the boundary, had to be stretched out over and over again. The links started to stretch, just a bit, throwing off the measurements. Somewhere along the line, the surveyors got themselves a fresh chain, at least once.

The result is a boundary that is a compound of degraded arc sections. Subtle, and maybe even silly. But true.

Strange Maps also points out that the boundary was described as everything within the 12 miles up to the shoreline of what is now New Jersey. The result of that, and of a 1930s Supreme Court decision, has been that the state boundary is, in fact, the mean-low water line as it existed in 1934. There are places where the shoreline on the Jersey side has filled-in and moved out, by accretion, to where it now lies within Delaware.

We try not to point this out too explicitly; it upsets our neighbors in New Jersey. That, and the fact that Delaware regulates what happens over the river bottom, which has so far stymied a proposed Liquid Natural Gas terminal in the Camden area.

The second "Where Delaware Met Pennsylvania" post looks at the "Wedge". This is a wedge-shaped bit of land that for a time was not in Delaware, not in Pennsylvania, and not in Maryland. It was another anomaly caused by the 12-mile circle and by a disconnect between what 17th-Century cartography expected to find and what 17th-Century surveying actually did find.

It's that bit beneath that "shelf" where the three states meet. Just above Newark.

I understand that it was briefly a haven for outlaws, who would flee there because no lawmen had jurisdiction. At least, until the states got together and decided to make it part of Delaware.

This almost forgotten bit of history lives on in some of the place names north of Newark like "Top of the Wedge" or "Wedge Hills."

These are just a few of the many strange truths about the Delaware border. For example, many of us in Delaware actually live east of the Mason-Dixon line. They drew our western boundary before turning west to create the part of the line that they are most known for.

Also, the Delaware boundary is the only one in the marked, in part, with boundary monuments made of stone from a different country. Mason and Dixon used a "light buff oolitic limestone cut on the Isle of Portland, Dorsetshire, England" to mark parts of the line.

The Delaware Geological Survey maintains a database of the boundary markers, some of which can be visited.