46. Watson's Mill and Dickinson House

Construction: Watson’s Mill (1860) | Carriage Shed (c. 1860) | Dickinson House (1867)

Architects: Unknown

Location: Watson’s Mill, 5525 Dickinson Street | Dickinson House, 1127 Mill Street, Village of Manotick


Watson’s Mill, Dickinson House and the Carriage Shed form the core of Dickinson Square, an enclave of heritage buildings in the historic centre of Manotick, Ontario.

The village of Manotick was named by founder Moss Kent Dickinson (1822-1897) after the Ojibway word meaning “Island in the River.” In 1858, Dickinson and his business partner Joseph Merrill Currier (1820-1884) leased the water power rights at the present site of Watson’s Mill along with 30 acres of the surrounding land from the federal government.

They constructed the Long Island Mill in 1860, a flour and grist mill rising 3 ½ storeys on the Rideau River side. The 2-storey front elevation follows a symmetrical 5-bay Georgian design. Built of locally quarried limestone, the Mill has squared, uncoursed rubble stone walls and cut stone trim with a bush-hammered finish. The walls are 1.2 metres thick at the base, reducing in thickness by 15 cm at each floor level to carry the floor joists. None of the interior hand-hewn square timbers are less than 30 cm square.

The Carriage Shed was built circa 1860 as a drive shed for farmers to stable their horses while using the Mill.

In 1863 Dickinson became the sole owner of “Long Island Milling Enterprises,” which by then had expanded to include a saw mill and carding mill. 

In 1867, he constructed a 2 ½-storey, gable-roofed clapboard house across from the Mill. Dickinson House has a symmetrical 5-bay front elevation following the Georgian style with a timber architrave framed entrance covered by a simple overhang supported on decorative brackets and flanked by pilasters.

After Dickinson’s death in 1897, the buildings remained in the family until 1929, when the Mill was sold to Alex Spratt.

Harry Watson, a former Spratt employee, took over ownership in 1946, changing the name to Watson’s Mill.

In 1972, the Rideau Valley Conservation Authority (RVCA) purchased the Mill, Dickinson House and the Carriage Shed with financial assistance from the federal and provincial governments. As the RVCA expanded, it bought other adjacent buildings and the area became known as Dickinson Square.

Watson’s Mill, Dickinson House and the Carriage Shed were designated under Part IV of the Ontario Heritage Act by Rideau Township Council on March 1, 1979.

Dickinson House was renovated in 1980 using designs by conservation architect John Leaning. Watson’s Mill was restored as an operating grist mill at the same time.

In 2006 the RVCA declared its intention to sell the historic properties to help finance a move to new purpose-built headquarters on Rideau Valley Drive. The battle to “Save Our Square” was led by Bonnie Gray, president of Watson’s Mill Manotick Inc., a non-profit group set up in 1997 to manage Watson’s Mill.

To help raise awareness and support, Heritage Ottawa covered the story in its Newsletter. In the April 2006 issue, board member Gordon Cullingham called readers to take action:

“[Save Our Square] is urgently looking for solutions that will preserve the square
and all its buildings intact and keep them publicly-owned. … The campaign is just
beginning… write to the Mayor, your Councillor, the Councillor for the location,
even your and Manotick’s MP and MPP and plead for the life of Dickinson Square.”

In 2008, the City of Ottawa responded by purchasing Dickinson House and the Carriage Shed, along with other RVCA-owned buildings adjacent to the Square.

The Manotick Mill Quarter Community Development Corporation (MMWCDC), a non-profit corporation which has since dissolved, was created by the City of Ottawa with a mandate to preserve and promote the heritage character of the Square.

In order to recover the $2.4 million invested in the site, MMWCDC developed a cost-recovery plan through property sales and long-term leases.

Although several properties were sold, no viable purchase offers were made for Dickinson House or the Carriage Shed. The City retained ownership of both and entered into long-term leases with new occupants.

Dickinson House is operated as a historic house museum by the Rideau Township Historical Society.

The Watson’s Mill property was transferred to Watson’s Mill Manotick Inc. in 2008, which also runs a used book store in the Carriage Shed. Watson’s Mill remains the only working museum in the Ottawa area and one of very few operating industrial heritage grist mills in North America.


CLICK HERE for a 3D Virtual Tour of Watson's Mill.

CLICK HERE for a 3D Virtual Tour of Dickinson House.