Photograph by Matthew Worden

Fort Reno Park, in DC’s Tenleytown neighborhood, is on some of the area’s highest ground, making it a good place to store water for distribution by gravity. ThisNorman-style water tower was built in the early part of the 20th century.

The drought that gripped Washington in the summer of 1966 was one for the record books. Already suffering from several straight years of below-normal rainfall, the region watched and sweated as the precipitation deficit mounted. From May through August, when usually about 16 inches of rain fall to wet our lawns and keep the Potomac flowing, the gauges measured just 7 inches.

In the Maryland and Virginia countryside, it was a tough year for farmers. Clouds of dust rose from the hard-baked soil as it was prepped for spring planting, ponds and wells began going dry, and most of the counties around Washington were declared federal disaster areas. A dairy farmer in Herndon told the Washington Post his hay crop “wouldn’t feed a goat,” and yields were down in corn, soybeans, tobacco, peanuts, apples, peaches, and tomatoes. At the farmers market in Bethesda, the supply of sweet corn was so short that the price rose to a shocking $1 for a dozen ears.

In the heart of the District, lawns were brown and public fountains were shut down to preserve water—all reminders that drought may develop slowly but has devastating effects. Lady Bird Johnson, the First Lady who had made beautification of the landscape a national cause, was saddened to hear that hundreds of trees just planted along the Baltimore-Washington Parkway were dying and that watering of the White House flower beds was being curtailed. She issued a plea for citizens to dump leftover dishwater on their trees and shrubs.

The situation became so dire in late summer that DC declared its first “water emergency” in more than a century. The city, along with some suburbs, imposed restrictions on water use, prohibiting the watering of lawns and gardens, the use of hoses to wash cars or clean streets, and the filling of swimming pools. Police patrolled the streets watching for violations in suburban Maryland, and a Goodyear blimp was used to monitor the dwindling level of the Potomac.

The river, source of much of the region’s water supply, was checked each day with growing concern. The water utility in suburban Maryland piled sandbags in the river to dam up a bigger pool to feed its intake. The Washington Aqueduct, which supplied water to DC and parts of Northern Virginia, pumped water out of the river into the Chesapeake & Ohio Canal, where it could be stored in case the river got any lower.

Maryland senator Charles Mathias, after a trip upriver, reported that there were places “where you can walk across . . . without getting your feet wet.” At Great Falls, teenagers proved the point by hopping rocks from the Maryland shore to Virginia in what looked like a little mountain brook. “What we need,” Mathias said, “is a hurricane.”

By September the Potomac was down to a level not seen since the Depression-era drought of 1930. On September 11, the Potomac’s daily flow at Chain Bridge was a record-low 374 million gallons. With demand at 291 million gallons a day, we were sucking up all but 83 million gallons of the river’s life-giving water. That left barely enough to keep the fish alive.

Then, suddenly, the crisis ended. It was not the hurricane that Mathias hoped for, but on September 14 a big storm rolled in and settled for several hours over the thirsty region. It rained 4½ inches, the biggest soaking in nearly four years, enough to bring the Potomac back to life and put several local creeks over their banks. The drought had been washed away, but it left behind a worry about what could happen when a city goes dry.

Water covers nearly three-fourths of the earth’s surface and makes up more than half of the human body. Without water, plant and animal life is impossible. Cities such as Washington that ordinarily have lots of water are the envy of arid places like Los Angeles, which must import water by aqueduct from the Sierra Nevada mountains hundreds of miles away. Water is a matter of life or death: The oases of the Sahara and the watering holes of the Old West are symbols of survival and water is so essential that it can inspire the sort of violence on display in the movie Chinatown. Even where water is plentiful, it is often not clean, healthy, and drinkable—a situation that prevails from the slums of Latin America and Africa to India’s sacred Ganges. No wonder stockbrokers are touting the idea of investing in water—they call it “the oil of the 21st century.”

Though water in Washington is as renewable as the rain, delivering it to customers is anything but simple. Three nonprofit, self-financed public utilities—the Washington Aqueduct, Washington Suburban Sanitary Commission, and Fairfax Water—treat and distribute most of the region’s water, though several other public agencies, including the DC Water and Sewer Authority, buy water wholesale from the big three and pass it on to customers through their own pipes. It is a complex feat of engineering involving several Potomac intakes, reservoirs, and treatment plants as well as dozens of water-storage tanks, hundreds of fire hydrants, many pumping stations, and thousands of miles of mains to reach more than 4 million consumers. Together the big three maintain more than 170,000 valves, including some very expensive ones that are six feet in diameter. Parts of the system in DC date back nearly 150 years.

Except for water towers on the horizon, much of this infrastructure is hidden and taken for granted. “Ninety percent of our assets are buried,” says one utility official, “out of sight, out of mind.”

While we’re accustomed to electrical outages, late flights, traffic jams, and delayed subway trains, hardly ever do we turn on a faucet and get no water. Such reliability has developed over many decades, starting in DC before the Civil War then spreading into its suburbs—a story that is a metaphor for Washington’s growth.

But many consumers have questions about system vulnerabilities: With Washington adding thousands of new residents each year, could another drought leave us with a catastrophic shortage? Is the water always safe to drink, or are we likely to see repetitions of the 2004 lead-contamination scare in DC? Is it possible that terrorists could kill thousands of people by dumping a toxic substance into our water?

DC Begins Tapping the Potomac

Patty Gamby, an engineer with the Washington Aqueduct, is dressed in hip-high rubber boots and a white hardhat, her flashlight providing the only light in the big circular tunnel. Her boots make a splashing sound as we move through six inches of water, and we can hear from above the thump-thump-thump of car traffic on MacArthur Boulevard as it narrows to one lane crossing Cabin John Bridge. Flipping on her radio, she tells an above-ground safety crew of our location: “We’re entering the bridge now.”

She is on an inspection tour of “the Conduit,” which carries raw Potomac River water from an intake just above Great Falls down to the Dalecarlia Reservoir on the Maryland/DC line, where it will be sent on for treatment. The conduit is drained and inspected inch by inch every two years. Nine feet in diameter and nearly ten miles long, lined with bricks and concrete, it carries millions of gallons of water each day.

Gamby has been doing this for years, so she is familiar with the stuff that slips through the intake’s screens and comes roaring down the conduit with the water. There are small rocks along with clumps of leaves and a couple of inches of river sediment. In pools of shallow water are a few small fish and eels, which sometimes are as big as a man’s arm. “Once,” she says, “I found a child’s doll.”

There are a few grotesque tree roots that have grown between the bricks and hang down in the darkness—their locations noted so that crews above ground can cut down the offending trees. Gamby also records all cracks that might be dangerous and puts them on a repair list.

But they are rare. That is all the more surprising because the conduit dates to the Civil War era—a project constructed by slaves and immigrants just as America was entering the industrial age. “No matter how many times I walk through here,” Gamby says, “I am always amazed that it’s still in such good shape.”

For several decades after Washington’s founding in 1790, its residents got water for themselves and their horses from cisterns, wells, and springs—some private and some owned by the new federal government. Spring water was first piped to the White House in 1816 and to the Capitol a couple of decades later—at first through bored-out logs, later through cast-iron pipes.

The shortcomings of this arrangement were evident by the 1850s. The city’s population, about 3,000 in 1800, was up to 58,000. Wells sometimes became polluted by sewage, and waterborne diseases, especially typhoid fever, were a threat. Water for firefighting was inadequate, a matter emphasized on Christmas Eve 1851 when a spark from a stove in the Capitol destroyed the room housing the Library of Congress.

All of this prompted Congress to appropriate money to plan construction of a new water-supply system, a task that was assigned to the US Army Corps of Engineers. That made sense, partly because Washington was a federal district but also because West Point was then the country’s only source of professional engineers. The officer put in charge was Lieutenant Montgomery C. Meigs, an ambitious young man who would become one of the most important builders in the city’s history. Besides the water-supply system, Meigs was the key figure in finishing the Capitol dome, in creating Arlington National Cemetery, and in designing and constructing the Old Pension Building (now the National Building Museum).

Within three months Meigs produced a 55-page plan that even now is the basis of DC’s water-supply system. He studied the systems in America’s biggest cities—New York, Boston, and Philadelphia—as well as those of Paris and London. Their big mistake, he concluded, was thinking small and ending up with a system that could not keep pace with a growing population. He envisioned, as appropriate for the capital of a great republic, a city adorned with towering fountains in the manner of ancient Rome.

Though some had proposed using Rock Creek as a source of water, Meigs recognized that Washington’s real good fortune was the Potomac, which delivered huge amounts of water right into the heart of the city. The river, which had been central to the decision to locate the capital here, stretched nearly 400 miles to the north and west, draining nearly 15,000 square miles in four states.

Meigs the engineer also realized the significance of Washington’s location on the “fall line,” the geological formation downriver from Great Falls where the elevated Piedmont Plateau gives way to the low-lying Coastal Plain. The difference in elevation there meant that water could be moved into the city entirely by gravity, a crucial advantage in an age when steam pumps were primitive and long before the invention of electrical pumps. By building a water-pooling dam and an intake just above Great Falls, Meigs could use the falling elevation to propel water south through his proposed conduit to Dalecarlia Reservoir and beyond. (The required slope is only 9½ inches per mile.) Just as crucial was the fact that the water above Great Falls was fresh instead of the brackish tidal water farther down the river.

This project began in 1853 and became known as the Washington Aqueduct. Its history is recounted in an excellent book by Harry Ways, who is retired as the institution’s chief engineer. During construction, the project had its own wharf in Georgetown to receive bricks, cement, pipes, and valves; dozens of horses and mules; canal boats to move sandstone from the Seneca Quarry; and more than 2,000 workers. There were many difficulties to overcome: irregular appropriations from Congress; criticism that the people of Washington rather than the federal government should be paying; illness among workers as well as excessive drinking; land speculation along the route; and fear of a Confederate raid during the Civil War.

One of the project’s most unusual features was Cabin John Bridge, which carried the conduit at a height of 100 feet over Cabin John Creek. Today, with a single lane and stoplights to control one-way traffic, the bridge may seem like a nuisance to commuters. But when it was completed in 1863, it was, at 451 feet, the longest single-arch masonry bridge in the world. The name of Montgomery Meigs is carved on the bridge’s side, as is that of Jefferson Davis, the secretary of War when the project began; Davis’s name was removed when he became president of the Confederacy but restored in 1908 by President Theodore Roosevelt.

Meigs also created two small reservoirs, both landmarks along present-day MacArthur Boulevard, to store the water delivered via the conduit and to allow river sediment to settle out before the water was distributed. Farthest north, at the DC line, was the 50-acre Receiving Reservoir (now called Dalecarlia Reservoir), created by damming Little Falls Branch. Two miles south was the 36-acre Distributing Reservoir (now called Georgetown Reservoir), a rectangular pool that features a small castle, added in 1902, that resembles the insignia of the Army Corps of Engineers.

The water moved from these reservoirs into Georgetown, where some of it was lifted by a pump to a brick-domed storage reservoir on high ground now occupied by the Georgetown branch of the DC Public Library. Big cast-iron pipes carried water across Rock Creek at Pennsylvania Avenue—pipes that were arched to do double duty supporting a traffic bridge and that are still in use today, though the bridge has long since been reinforced. From there the water traveled into the center of the city and to the Capitol and the Navy Yard, nearly 19 miles from its origin at Great Falls—all by gravity. To show off this feat, Meigs created a public fountain at the foot of Capitol Hill, where the pressure was enough to shoot water 100 feet high.

Complaints soon arose, given that the system had limited ability to get rid of suspended sediment and no chemical treatment. One citizen, who had expected water that would be “as bright and clean as liquid diamond,” found that it often was turbid—“the muddiest, dirtiest water that ever went down the throats of human beings.” Pressure was too low, especially when the Navy Yard was drawing lots of water or people were taking their weekly baths. Without disinfecting treatment, typhoid fever remained a problem.

The situation was rectified by a series of improvements in the early 20th century. A deep tunnel was blasted out of bedrock from the Georgetown Reservoir across town to deliver water to a new 38-acre McMillan Reservoir just east of Howard University. There the water was put through a new filtering system using sand; additional protection came with the introduction of chlorine disinfection in the early 1920s. Many of the old sand filters, which were abandoned in 1985, still stand just south of Washington Hospital Center.

Other elements of the current system have been added over the years—a second conduit from Great Falls to Dalecarlia Reservoir (1927), a new treatment plant on MacArthur Boulevard (1928), a new dam and intake at Little Falls (1950s), and a replacement treatment plant at McMillan Reservoir (1985). Washington Aqueduct also has some of the largest water-storage facilities in the region, built on high elevations to create the pressure to serve large sections of the city. One of the biggest, at Fort Reno in DC’s Tenleytown, holds 20 million gallons underground.

DC’s water system is complicated by the fact that while the Washington Aqueduct continues to produce the city’s water under the auspices of the Army Corps of Engineers, many of the distribution mains, pumping stations, and additional storage tanks are under control of the DC Water and Sewer Authority. WASA, which buys water wholesale from the aqueduct, is a semiautonomous agency created in 1996 so that the water system no longer would be a department within the DC government. The change was prompted by the diversion of millions of dollars from water bills to other city departments, leaving the water utility a dysfunctional operation with a big backlog in maintenance.

Water to Keep the Suburbs Green

Long after DC got its first taste of Potomac River water, the adjacent jurisdictions in Maryland and Virginia remained sparsely populated and dependent on wells. But Arlington, Alexandria, Fairfax County, Montgomery, and Prince George’s were poised for development, and a ready supply of clean water was essential. Beginning as early as the 1890s in a few places, but with sprawling force after World War II, these jurisdictions were transformed into modern suburbs. Between 1920 and 1970, those five jurisdictions grew from 120,000 residents to almost 2 million, which translated into lots of baths and garden hoses.

The suburban water-supply system began developing first on the Maryland side of the river. The key event, in 1918, was creation of the Washington Suburban Sanitary Commission, which was promoted by Democratic political boss T. Howard Duckett of Prince George’s County. The commission was set up to provide both water and sewer service to the populated parts of both Prince George’s and Montgomery—a situation that has prevailed ever since.

The WSSC began to buy existing water systems, some run by municipalities and some by developers or other private owners. These purchases merged Chevy Chase, Edgemoor, Glen Echo, Kensington, Takoma Park, and Mount Rainier into a single system, and new mains were built to serve growing communities including Silver Spring and College Park. Only Rockville, Montgomery’s county seat, remained apart, even today operating its own plant to process water from the Potomac. The WSSC’s first treatment plant, a sand-filter operation in Hyattsville, was built in 1920 and drew water from a branch of theAnacostia River.

To meet the demand for water, which grew with every new subdivision, WSSC first looked east to the Patuxent River, which forms the border between Montgomery and Howard counties and farther south between Prince George’s and Anne Arundel. It built the Brighton Dam on the Patuxent in 1944, creating the 800-acre Triadelphia Reservoir, then expanded in 1954 with the T. Howard Duckett Dam, which sits farther downriver and forms the 800-acre Rocky Gorge Reservoir. Water from these reservoirs goes to a treatment plant near Laurel, which produces about a third of WSSC’s output. The remainder comes from a treatment plant in western Montgomery that was opened in 1961 and draws water from the Potomac River.

In Northern Virginia, where wells were once the norm, a different system emerged. Arlington, one of the first suburbs to develop, got permission to buy water wholesale from the Washington Aqueduct in 1927, and water from the Dalecarlia treatment plant in DC flows into Virginia via a main underneath Chain Bridge. Since 1947 there has been a similar arrangement between the Washington Aqueduct and the city of Falls Church, which in turn passes water on to part of Vienna and various northern Fairfax County neighborhoods, including McLean. Through a main that runs under Key Bridge, the aqueduct also has supplied water to the Pentagon and Reagan National Airport since they were built in the 1940s.

Alexandria, the river town that had been here before creation of the capital, had one of the area’s oldest water systems. Its privately owned utility, now known as Virginia American Water, built Lake Barcroft, near Baileys Crossroads, in 1915 and drew water from there for decades. But it sold the lake in the early 1950s and built a dam creating the Occoquan Reservoir on the Fairfax/Prince William line, allowing it to serve customers both in Alexandria and in such emerging suburbs as Dale City.

By the mid-1950s it was Fairfax County—soon to be traversed by the new Beltway—that was poised to become the economic behemoth of Northern Virginia. For that, it needed a bigger, more unified water utility than the existing patchwork of well-based systems, each with a few hundred customers. The solution was the creation in 1957 of the Fairfax County Water Authority, an independent agency that soon bought and tied together more than 20 small systems. After a legal battle in the 1960s, it took over distribution lines in southern Fairfax County owned by Virginia American Water as well as the company’s Occoquan Reservoir and treatment plant. Fairfax City remained independent, getting its water from Goose Creek Reservoir, which it built in Loudoun County in the late 1950s.

The Fairfax Water Authority—now known as Fairfax Water—has expanded along with the explosive population growth of Northern Virginia. It opened a big treatment plant near Herndon in 1982 to draw water from the Potomac and has just replaced its old Occoquan plant with one nearby on the site of the former Lorton prison. Sixty percent of its water now comes from the Potomac and 40 percent from the Occoquan. About 45 percent of the water is sold wholesale to other water systems that do not have their own treatment plants. Some of this water goes to Dulles Airport, Fort Belvoir, Herndon, and parts of Vienna as well as Alexandria, whose system is still owned by Virginia American Water.

Water systems in Washington’s exurbs are more patchwork, with wells the norm in rural areas and fully developed distribution systems serving new subdivisions. In Maryland, Frederick County gets much of its water from the Potomac, while the city of Frederick draws from three smaller waterways. Howard County buys water from the city of Baltimore and a smaller portion from WSSC. Anne Arundel County buys water from Baltimore, too, but relies mostly on municipal wells, as do Charles, Calvert, and St. Mary’s. In Virginia, high-growth parts of Loudoun and Prince William counties, including Dale City, get water wholesale from Fairfax Water. But Leesburg has its own system drawing water from the Potomac, and Manassas and Manassas Park get their water from Lake Manassas, which was created by damming Broad Run in 1971. Stafford County supplies its own water from two small lakes.

Suburban water utilities confront a public-relations problem in locating pumping stations and water towers, which are essential to their operations but which residents disdain as overpowering intrusions. The solution in some cases is camouflage. One local utility stores millions of gallons of water under a bank of tennis courts and has pumping stations disguised as a barn, a mansion, and a modest brick home in a quiet subdivision. The clever disguises seem to work—the brick house once aroused interest from a real-estate agent.