Flowing 23.5 miles through the hills and valleys of Westchester County, New  ork, the Saw Mill River has long shaped the communities along its banks—from its early days as a resource-rich stream for Native Americans, through the rise and fall of water-powered industry, to its present role in urban restoration and environmental renewal.

The Name and Native Roots

Before European contact, the river was known to the indigenous Lenape people as Nepperhan or Nepeckamack, meaning “fish-trapping place.” The river served as a rich natural resource, teeming with eels and freshwater species, and functioned as a tribal boundary line. The name “Saw Mill River” originated later, named after one of the first European mills built along its course—likely Adriaen van der Donck’s sawmill near the river’s mouth in the 1640s. The Dutch referred to the stream as the “Saeck-kill,” a term that eventually evolved into “Saw Mill River.”

Van der Donck and the Colonial Mills of Yonkers

In 1646, Van der Donck obtained land from the local tribes, confirmed by a patent from the Dutch West India Company. By 1649, he had established a primitive sawmill at the river’s mouth. The site later passed to Frederick Philipse, who acquired the Yonkers tract beginning in 1672. Before the end of the century, Philipse built a mill near Van der Donck’s original location, setting the stage for Yonkers’ industrial rise.

After the Revolutionary War, Philipse Manor lands were confiscated by the state and sold by the Commissioners of Forfeiture. In 1785, the manor house and 320 acres were sold and later purchased by Lemuel Wells in 1813. A map of the Wells estate reveals mill ponds at multiple levels, including five mill buildings used for grinding grain and plaster, sawing timber, and fulling cloth.

The Saw Mill River in the American Revolution

Though overshadowed by the Hudson River in larger military campaigns, the Saw Mill River was a key strategic corridor during the American Revolution—especially in the contested region of lower Westchester County, known as the “Neutral Ground.”

A Natural Defensive Barrier

The Saw Mill River flowed north-south, roughly paralleling the Hudson River, with a steep, rugged terrain and limited crossings. The adjacent Saw Mill River Road was a major route used by both British and Continental forces for inland movement. Control of this road—and by extension, the river—was vital to troop and supply logistics.

Guerrilla Warfare and Local Resistance

According to local tradition, patriot John Dean conducted guerrilla-style ambushes against British troops from behind a large boulder located on William and Catherine Yerk’s farm in Mount Pleasant. The river’s twists, stone outcroppings, and wooded banks offered ideal cover for such irregular operations. Stories like Dean’s reflect the kind of hit-and-run warfare that defined the Neutral Ground, where neither side held full control and local fighters became a constant threat.

Continental Fortifications and Yankee Dam

To slow potential British advances, Continental forces built forts near present-day Hawthorne, at the junction of the Saw Mill River and Flykill Creek, a tributary. This location corresponds roughly to the modern junction of the Taconic State Parkway and Saw Mill River Parkway. There, they constructed the so-called Yankee Dam, designed to flood the area and create a man-made lake to obstruct troop movement and wagons. On historical maps predating the construction of the parkways, what appears to be the Flykill Creek can be seen flowing into the Saw Mill River near present-day Hawthorne, marking the likely site of this strategic confluence.  

Though little known today, this strategic use of natural geography and early infrastructure was consistent with Continental tactics across the Hudson Valley, where rivers and roads became battlegrounds of maneuver, attrition, and control.

The Rise of Industry in Yonkers

By 1835, Gordon’s Gazetteer listed Yonkers as having a population of 1,879 and thriving industry:

• One grist mill producing cornmeal for export
• Two sawmills sawing pine
• Four sawmills sawing mahogany
• A hat factory producing 100 hat bodies daily

With daily steamboat connections to New York City and abundant water power, Yonkers was ideally situated for industrial growth.

F.W. Beers’ 1867 atlas of Westchester County documents the full development of six water power levels in Yonkers, labeled the First through Sixth Water Powers. The First Power, originally Philipse’s pond, sat at 17.76 feet above the Hudson. The Sixth, located in “The Glen,” was at 89.15 feet.

These sites supported:

• Gristmills
• Sawmills
• Carpet factories
• Hat and silk manufacturing
• Machine shops
• A brewery

Decline of the Mill Ponds

By the 1880s, the rapid growth of population and industry turned the mill ponds into open sewage basins. Contaminated with both human and factory waste, they became a public health hazard. In response, the ponds were drained in 1892. While the industries they once supported transitioned to steam, the days of water-powered industry on the Saw Mill River were over. Water power, subject to seasonal and flow-based limitations, was no longer viable for large-scale industrial use.

Mills Upstream: From Woodlands to Chappaqua

Beyond Yonkers, mill sites dotted the river’s course up to its headwaters in Chappaqua, nearly 20 miles north and 450 feet above sea level. These locations reflect a patchwork of colonial enterprise, post-Revolution expansion, and 19th-century mechanization.

Woodlands Lake (Howland’s Mills)

The riverbed rises gradually north of Yonkers, and the next major mill site was located at present-day Woodlands Lake. A 1785 map of Philipse Manor marks a sawmill operated by John Lentz near this location. Joseph Howland, a former owner of the Philipse Manor House, purchased the site in 1816. The mills—on both sides of the river—saw various uses including cider pressing, lumber, and grain processing.

Later, the property was acquired by Cyrus W. Field of Atlantic Cable fame, who attempted to modernize the mills with steam power. However, the venture was unsuccessful, and the mills were torn down by 1894. Today, remnants including the mill canal, sluiceway, and foundations remain visible in Woodlands Park.

Brown’s Mills at Eastview

Brown’s Mills at Eastview were the largest and last mills operating with water power along the Saw Mill River. When fire destroyed them in 1920, the property included:

• A grist mill
• A sawmill
• A cider mill
• An icehouse

Early records show the Commissioners of Forfeitures sold 244 acres in 1785 to John Yerks, who later sold 14 acres for £91 in 1793. By 1814, the property had grown in value, selling to Peter and George Lorillard for $5,000. Though they had a snuff mill on the Bronx River, it’s unclear if they intended one for Eastview. In 1817, the property passed to Abraham Hammond.

John O. Brown acquired it in 1841, and his descendants operated the mills until the 1920 fire. The ruins of the dam and mill foundations still remain.

Hawthorne and Chappaqua

In Hawthorne, a small dam and mill foundation remain near the Staats Hammond house. Beers’ 1867 atlas marks this as Unionville, home to a gristmill and sawmill operated by C. Bird.

Chappaqua’s mills, established before 1830, included two ponds—one called the “fulling mill dam,” the other the “great saw mill pond,” later known as Chappaqua Lake. R.L. Birdsall owned the Chappaqua Mills in 1867. Charles B. Griffith later owned the gristmill, which was torn down in 1894. The pond became known as Hunt’s Pond after one of the lessees.

These mill dams were typically built with dry-laid fieldstone walls and earthen embankments. Some, like Howland’s Pond and Chappaqua’s lower pond, have been preserved and integrated into the Saw Mill River Parkway parklands.

The Social Role of the Mills

These mills were central to life in Westchester. Farmers brought logs to be sawn into lumber for barns, homes, and churches. Grain was ground into flour and feed. Cider pressed in the autumn flowed through the valleys.

Mills were also social hubs, where isolated neighbors exchanged gossip, bartered goods, and forged community ties. Roads often led from farms to the valleys, shaped by the need to reach these mills, sometimes under treacherous conditions.

Flooding and Recovery Along the Saw Mill River

As suburban development surged in the 20th century, many communities along the Saw Mill River—particularly Chappaqua, Hawthorne, and Elmsford—began experiencing chronic flooding. The loss of wetlands, construction of paved roads and buildings, and narrowing of the river’s natural floodplain all contributed to a rise in stormwater runoff. Heavy rains routinely overwhelmed the riverbanks, turning streets and highways, especially the adjacent Saw Mill River Parkway, into temporary rivers. Flash floods in the late 1990s and early 2000s swamped homes, businesses, and roadways, prompting widespread damage and mounting concern. In some storms, cars were left stranded nearly submerged, and entire neighborhoods saw basements and first floors inundated.

To counteract these threats, local, state, and federal agencies undertook a series of flood mitigation and restoration projects. In Chappaqua, the Army Corps of Engineers re-channeled the river through the village center, while in Elmsford and Ardsley, debris removal, elevation of flood-prone homes, and bridge upgrades were implemented. Though some projects improved local conditions, others inadvertently worsened flooding downstream, underscoring the need for regional coordination. More recent efforts have focused on restoring wetlands and floodplains, improving culverts, and discouraging development in vulnerable areas. These actions, combined with habitat restoration and public education campaigns, reflect a growing commitment to managing the Saw Mill River as both a community resource and a dynamic natural system.

Modern Restoration and Daylighting Efforts

During the early 20th century, much of the Saw Mill River was buried in culverts to make way for development. In downtown Yonkers, the river’s final stretch was hidden until 2012, when the first phase of the Saw Mill River Daylighting Project opened at Van der Donck Park.

This restored portion reintroduced the river as a public plaza, wildlife habitat, and stormwater control feature. It now attracts herons, fish, and community visitors and is part of a broader environmental and urban renewal plan.

The river’s watershed still supports over 110,000 residents, and restoration projects have focused on:

• Habitat and wetland recovery
• Invasive species removal
• Pollution reduction
• Public education and access

Conclusion

The Saw Mill River has been a dynamic force in the shaping of Westchester County—from Lenape fishing grounds to Dutch and British colonial mills, from a guerrilla battleground of the Revolution to the industrial engine of Yonkers and beyond.

Though the river’s industrial utility waned, its story didn’t end. Through modern conservation and restoration, the river is once again a living, visible part of the communities it shaped, flowing with new life and echoing the past in every turn.