Synopsis
Our systems of infrastructure are not only shrouded in mystery, many are woefully out of date. In "On the Grid", Scott Huler takes the time to understand the systems that sustain our way of life, starting from his own quarter of an acre in North Carolina and travelling as far as Ancient Rome. Each chapter follows one element of infrastructure back to its source - or to its outlet. Huler visits power plants, watches new asphalt pavement being laid, and traces a drop of water backward from his faucet to the Gulf of Mexico and then a drop of his wastewater back to the Atlantic. He reaches out to guides along the way, both the workers who operate these systems and the people who plan them. Mesmerizing and often hilarious, "On the Grid" brings infrastructure to life and details the ins and outs of our civilization with fascinating, back-to-basics information about the systems we all depend on.
Extrait
chapter 1
THE LAY OF THE LAND
A surveyor's total station looks something like a movie camera. A rotating lens set in a tough yellow metal housing sits about head high atop a firm, heavy tripod. It measures exact distances by bouncing an infrared signal off a reflector on a pole; it also measures angles to an accuracy of a second or so (less than 1â?"1,000,000 of a circle). A total station showed up at my house one day in the company of Sherrill Styers, a cheerful, slow- moving surveyor in a broad-brimmed hat, T-shirt, and pants held up by suspenders. I'd invited him over because I figured the place to begin understanding how infrastructure got to my property was on my property itself--the ground infra which all those structures lay. Surveying occupies itself with knowing exactly where you are, in all three dimensions. Sewer pipes need to be pitched at just the right slope; a backhoe swipe in the wrong spot can darken dozens of homes and disconnect hundreds of people from the Internet; almost any infrastructure project involves right of way, and nobody wants the city to have an inch more than it deserves. You have to know exactly where you are.
"People don't realize that when they see new roads going in," Styers said. "Before the bulldozers know where to cut or fill, they need surveyors to tell them where and how much." Styers talked as he set up to find my property's corners. He first used a metal detector to find what my deed calls an "existing iron pipe" at the front corner of my yard and dug a little hole to expose the metal bar. Then he set up the station above it, using spirit levels and hairline sights in the machine to orient directly above the center of that old iron bar, sunk there probably 90 years before. While I held the reflector, he took sightings to the corner of my house, the other property corner along the street, and the back corners of my property. Surveying, he explained, is trigonometry: You take extreme care to measure the length of a line, then you take sightings to a distant point from each end, measuring angles. "Then you've gotten your angle-side- angle," Styers said. "You can use the law of sines to calculate, and that's your distance." You use the calculated lengths as the bases of further triangles, in order to measure more angles and calculate more lengths.
Styers practices what he calls cadastral surveying, but is also called metes and bounds surveying: The surveyor starts at one corner monument and describes a trip around the property border, giving measurements (metes) from one landmark to another (bounds). Those landmarks tend to be monuments left by other surveyors: An old survey of my yard starts "at an existing iron pipe" and also mentions "an axle," which, like the pipe, was still right where it was supposed to be, a solid iron rod sticking a good foot out of the ground. "That looks like it could be from...a buggy, maybe," Styers said, opining that in 1918, when my property was platted, cars were taking over and buggy axles may have been losing value. Then he decided it might have been from a Model T. Either way, he liked it--it wasn't going anywhere, and it told you in no uncertain terms that you were at the corner of my backyard. Good, solid surveyor values.
A modern total station measures distances itself, though if the surveyor can't sight directly along a line (if, say, a tree is in the way), he or she has to, use the same triangulation method surveyors have been using for centuries. Some stations even use 2 Global Positioning System (GPS), but, as Styers comments almost dismissively, "your GPS equipment doesn't work too well beneath tree canopy." Google Earth can swoop in on your house, those latitude and longitude tickers spinning dramatically along, state and county borders of pale yellow and blue appearing and disappearing until you get that final view from the sky, shockingly clear, of T-shirts stopped midflap on your clothesline; that's very nice. But if you run into trouble with your neighbor about whose fence is on whose land, the courts will want to know about the piece of iron pipe some surveyor sank to mark your property corner 100 years ago, not what a GPS device says. "There are a lot of precedents set in court," another surveyor told me. "I'll give you an example: If your deed says you have a boundary of 200 feet, and it's from the oak tree to the maple tree, and when you measure it it turns out to be only 190 feet, it's still gonna be the oak tree and the maple tree. Regardless of what technology you use."
Or more simply: "What you buy is represented by your deed," Styers told me, peering along my property line at a privet hedge inconveniently growing directly on the boundary. "What you own is what a surveyor took a transit and a chain and went out there and sunk monuments in your property corners." Transit? Chain? Monuments? There's so much to learn.
Start with a surveyor joke: What does a surveyor say upon seeing Mount Rushmore? Answer: "Well, there's three surveyors, but who's that other guy?" That other guy is Teddy Roosevelt, the only one of the big four who never made his living surveying. The point being that surveying used to be a great way to get your life started: All you needed was a chain (a chain was 1â?"80th of a mile: 66 feet long, 100 links per chain, made of metal), a compass and transit (or some other instrument for accurately measuring angles between objects; the total station is the modern version), and a strong back. After that it was all hiking and trigonometry, and you could make a fine living in a growing country by pacing and setting the boundaries of the land constantly being bought, sold, settled, and connected. In fact, it was one of the true growth industries in a new nation whose greatest resource was almost limitless land.
Talk to a real estate agent or developer for a while and sooner or later he or she will say, "They're not making any more land." But that cliche has become true only in the last century or so. Until then, though new land wasn't being created, new land was constantly being explored, mapped, and usually, in recent centuries, seized from its occupants and made available to European settlers. In fact, the United States was from the outset, and in many ways continues to be to this day, fundamentally a great big land development scheme. "After the Revolutionary War, the United States was poor in everything but land, so real estate development became the chief source of entrepreneurship," Witold Rybczynski wrote in Last Harvest. This applies to Raleigh as much as anywhere, and perhaps a good deal more so, as I learned when I went looking for the history of that little quarter acre on which my particular node on the infrastructure grid stands.
Raleigh's state capitol sits at the top of a slight rise in the terrain, surrounded by a gridwork of streets, largely because an enterprising settler named Joel Lane appears to have gotten some commissioners from the brand-new state of North Carolina drunk enough to buy his property. It's a long story, plausibly true, and beloved by Raleighans. After the Revolution, legislators of the new state needed to plant their capital somewhere that would offend neither the coastal cities in the east nor the Appalachian settlers in the west. The great middle of the state was largely unsettled; Wake County, in 1792, still lacked a town of any description. The local Tuscarora Indians never had a settlement here, and even the European farmers working their way west seem to have found little here of interest: Of the 1,000 acres Lane eventually sold to the state, three- quarters were virgin forest.
With six sites under consideration, including several on the Neuse River, the commissioners remained deadlocked until they spent a night at the home of Lane, who allegedly served them a mixture of bourbon, sugar, and cherries called Cherry Bounce. The next morning the commissioners voted to buy Lane's 1,000 acres, which were several miles from the Neuse. Raleighans like to point out that their town sits where no town ought to be and that land development schemes can thus be said to be in Raleigh's DNA.
A surveyor laid out the town, basing the design on William Penn's for Philadelphia, with five squares arranged like the five-spot side on a die. The central square would hold the statehouse, the other four other state buildings or parkland. The main streets leading away from the middle of the center square along the chief compass points were designed to be 99 feet wide--exactly 11/2 surveyor's chains--for easy construction; all other streets were 66 feet wide--a single chain--which was even easier.
At that point my lot, on a ridge a couple of miles north of town, was likely oak-hickory forest, a naturalist has told me. But actually, the history of my lot starts long before that. Past is prologue: You have to look underneath, down to the bedrock. All those New York City skyscrapers rest secure because they're on the solid granite base of the island of Manhattan; those Oakland bridges fell down during the Loma Prieta earthquake because of the Jell-O soil they were built on; New Orleans floods because it's below sea level, and its continuing sinkage profoundly stresses those fragile levees. As geologist Kenny Gay told me in explaining what's beneath my lot in Raleigh, "Every little hill has reason and meaning. It's not random. Geology is a fundamental science, because everything else is derived from the geology."
About 500 million years ago, the ancient ocean Iapetus, situated between the proto-North American, European, and African landmasses, began closing up. The resulting squeeze did more than create the mountain range that eventually became the Appalachians. More important for my quarter of an acre, it took the sediments that had built up on the floor of that ocean and metamorphosed them into gneiss, a sparkling, gray, striated bedrock. The dirt on my lot turns out to be from a soil series called Cecil, the famous southern red clay. "The gneiss, when it decomposes, creates that classic sticky, red, stain-everything clay," Gay said. Granite, on the other hand, which forms the bedrock east of Raleigh, decomposes into a much sandier soil. Feldspars, common in granite, turn into a small-grained clay that the wind blows away, leaving behind a nice, sandy soil composed of quartz. It's great for growing cotton and tobacco, and you can still easily find both of those crops growing not 10 miles east of my house.
It's different to the west. "Not much wants to grow in that," Gay tells me. "So people plant grass--grass is one of the only things that grows." In fact, the red-clay land west of Raleigh was considered so valueless that for years it lay empty. When the Research Triangle Park developers showed up, they finally found something that would grow there: buildings. This was nothing Joel Lane hadn't known a couple of hundred years before. My lot was finally platted after World War I, when Raleigh still had fewer than 25,000 people, and the neighborhood was built mostly after World War II, at which point Raleigh annexed the neighborhood, sticky red clay or no. And new development remains a constant, turning the red clay of Wake County to civilization at the rate of close to 30 acres a day. I went out to see how the surveyors tell the bulldozers where to go.
Ron vanderhoof turns his red pickup off Yates Store Road and we begin driving backward in time. To be sure, along Yates Store we had drifted from finished houses to houses on dirt lots to empty lots, even passing one odd vista where paved streets wound among nothing but a forest of new Victorian- style streetlights, firm and thin like saplings in an orchard. But turn onto the unlabeled streets of phase three of the Amberly development (Amberly Three), and layers rapidly peel away. The pickup slows to a crawl as we leave asphalt and begin driving on gravel: subgrade, in the language of contractors.
The subgrade is unpaved but nonetheless bordered by concrete curb--there are machines now that squeeze out that concrete curb like toothpaste from a tube. Everywhere you look, the bones of the infrastructure stick out of the ground: metal boxes that protect connections to the electrical system; capped cylinders full of wires to connect telephone and cable lines; PVC pipes that reach down into the earth, grasping for sewer or water pipes. Drive a little farther and the subgrade vanishes, the road turning to red clay. Only the corners have curbs, and here and there a manhole cover is planted in the dirt; the storm and sanitary sewer lines are laid before the road is. And everywhere, waving from tall stakes in the ground, are gay little tape flags of bright red, blue, lime green--different subcontractors marking the spots where different elements of infrastructure will go.
If you want your water meter at the corner of a lot, not under the driveway, you'd better know exactly where you're digging. Same thing for hookups to the storm drain or sewer system: The difference between water moving in the right direction and the wrong direction is the difference between a basement and a swimming pool. Vanderhoof points out two stakes by a pile of 5-foot-diameter concrete pipe segments: the site of a future sewer manhole. The two stakes mark a straight line perpendicular to the center line of the road. "Each stake is marked with the distance to the center line," Vanderhoof explains--one is 25 feet, the other 35 feet--so workers have two measurements to make sure they find the right spot to start digging. It's a neat technique: simple, exact, and redundant. Vanderhoof smiles. He works for C. C. Mangum, the contractor preparing the site for the hundreds of houses that will be built there. His company grades the land, lays the roads, and buries the pipes and wires. Mangum is an infrastructure company, Vanderhoof is an infrastructure guy, and exactness is where he lives: He is Mangum's chief surveyor. So when he says 25 feet to the center line of the road, he means 25 feet, not 24 feet, 1115â?"16 inches.
But the stakes are not really what we have driven out here to see; in fact, we came to see the opposite. We drive even farther, to the end of the road, where bulldozers and graders trundle over fresh earth, gears grinding and signals beeping, and Vanderhoof points out what we do not see.
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