Over the course of 250 years, more than 20 mills relied on the water power flowing down Rock Creek.
Rock Creek valley was a high-tech corridor for 19th century Washington.
Using breakthroughs in automation, millwrights were able to tap the era's best energy source — the flow of water — to construct mills up and down Rock Creek. Mill owners further developed the region by building roads to connect their properties to area farms and to the few thoroughfares that led to the wharves of Georgetown and Washington city.
By mid-century, milling was the District's biggest industry. In addition to grist mills that made flour, other mills ground bone into fertilizer, carded wool, and turned out animal feed, paper,lumber or plaster.
Milling along Rock Creek had been a grueling business for more than a century, beginning in the late 1600s. Millers and their helpers hauled heavy sacks of wheat, corn and oats, manually sifted flour and packed it into bags and barrels. One of the earliest operations — White's Mill (later, Peters Mill) — took advantage of the strong rapids south of present-day Military Road. The creek also powered Lyons (or Federal) Mill on the opposite bank from Georgetown's Oak Hill Cemetery, Parrott's Mill a bit further south, Reed's and Deakins Mills by the mouth of Piney Branch, and the Patterson paper mill near P Street.
Then a Delaware visionary named Oliver Evans realized that gears, belts and pulleys could harness the movement of the mill's water wheel to do most of the back-breaking labor. Evans patented his methods and publicized them in a book printed in 1795, revolutionizing the industry.
Farmers who stepped into a mill built using Evans' system must have been dazzled by the constant motion, all happening automatically. Buckets arranged on conveyor belts lifted grain or flour from the basement to the attic, hoppers dropped precise amounts of grain onto millstones, mechanical rakes spread meal for drying, and rolling screens cleaned grain and sifted flour.
Many of the Rock Creek mills provided custom milling for neighboring farmers, who paid with a portion of their grain. The alternative, grinding flour for export, put mill owners in competition with large operations established along the Potomac River and the Chesapeake and Ohio Canal, where barges could be used to transport grain and flour.
For Some, a Profit Stream
No less a luminary than John Quincy Adams discovered that Rock Creek did not always provide a good flow of cash. One year before becoming President, he purchased the Columbian Mill on land that is now part of the National Zoo — but in the end pronounced it "a losing concern." The name Columbian was inherited from an earlier mill built on the site before 1800 in what was then the newly established District of Columbia.
Argyle Mill and Peirce Mill had greater commercial success — and the same man is credited with building both of these neighboring mills. As millwright Isaac Peirce began acquiring property in Rock Creek valley, he purchased Deakins Mill in 1794, which he replaced by building the state-of-the-art Peirce Mill in the 1820s. Because of a legal dispute over ownership of the Argyle estate just up the creek, Peirce was unable to purchase that property. But it's likely he was hired to construct Argyle Mill on the parcel sometime before 1800 — allowing him to try out the new technology before erecting his own mill.
Argyle Mill became known as Blagden's Mill after Thomas Blagden bought the estate in 1853. By 1860 his mill was turning out 4,200 barrels of flour per year. Meanwhile, over at Peirce Mill, as many as 12 wagonloads of wheat would arrive each day for grinding. To provide access to their businesses, the Peirce family laid out Peirce Mill Road and Joshua Peirce's (Klingle) Road in 1831, followed by Broad Branch Road in 1839. Blagden's Mill Road (originally Argyle Mill Road) was added in 1847.
Rock Creek also boasted at least 10 more mills upstream in Maryland with such familiar names as Jones Mill, Plyer's Mill, Veirs Mill and Muncaster Mill (which, in 1925, was the creek's last commercial mill).
By the late 19th century, newer technology was making the mills obsolete, including the use of metal rollers instead of millstones, rail transportation and steam power. As government became Washington's primary industry, grain production declined. Some of the mills were done in by the very creek that made them possible. The Johnstown Flood of 1889 devastated Blagden's Mill, whose ruins were removed during the construction of Beach Drive, and also washed away the remains of Adams Mill, which had closed in 1867.
Peirce Mill survived the flood and continued to make flour until the main shaft broke in 1897. Symbolically, its final millers — brothers Charles and Alciblades White — were descendants of the man who built White's Mill in the early days of Rock Creek milling.
Peirce Mill was restored in the 1930s and continued operating until 1958 to demonstrate a piece of local history — and provide flour to government cafeterias during World War II. Another renovation kept the millwheel turning from 1970 to 1993. After the latest reconstruction, undertaken by the Friends of Peirce Mill, the mill resumed grinding grain in 2011 — allowing today's Washingtonians to experience one of the technological marvels of the 19th century.