Southwest Branch Saint John River facts for kids

The Southwest Branch Saint John River (in French: Rivière Saint-Jean Sud-Ouest) is a river about 91.9 kilometers (57 miles) long. It flows through parts of Maine in the United States and Quebec in Canada. This river is special because a large part of it forms the border between these two countries! It eventually joins other rivers to form the main Saint John River.

River's Journey

The Southwest Branch Saint John River starts at "Little Saint John Lake." This lake is quite unique because it sits right on the border between Canada (Quebec) and the United States (Maine). The lake is surrounded by mountains.

Where the River Begins

Little Saint John Lake is located on the eastern side of a watershed. A watershed is like a big bowl where all the rain and snow that falls drains into a common river or lake. The water from the western side of this watershed flows into other rivers, like the Metgermette North River in Quebec.

The mouth of Little Saint John Lake, where the river begins its journey, is right on the Canada-US border. It's about:

• 2.2 kilometers (1.4 miles) south of a mountain peak in Maine.
• 8.6 kilometers (5.3 miles) southeast of the village of Saint-Zacharie, Quebec.
• 20.7 kilometers (12.9 miles) northeast of Armstrong in Saint-Théophile, Québec.

Flowing Along the Border

From Little Saint John Lake, the Southwest Branch Saint John River flows for 91.9 kilometers (57 miles). For about 54.6 kilometers (33.9 miles) of its upper part, the river acts as the official border between Canada and the United States.

During this part of its journey, the river winds and turns, collecting water from smaller streams that join it from both Quebec and Maine. It flows generally northward and then northeastward.

Entering Maine

After flowing along the border, the river enters Maine completely for about 37.3 kilometers (23.2 miles). Even when it's fully in Maine, some smaller streams from Quebec still flow into it. For example, Carter Creek, which mainly flows in Quebec, joins the river in Maine.

Joining Other Rivers

The Southwest Branch Saint John River continues its journey, eventually meeting the Baker Branch Saint John River. After this, it flows for another 15.9 kilometers (9.9 miles).

Finally, the Southwest Branch Saint John River joins the Northwest Branch Saint John River. This meeting point is considered the very beginning of the larger Saint John River. From there, the main Saint John River flows east and northeast through Maine, then east and southeast through New Brunswick, before emptying into the Bay of Fundy and then the Atlantic Ocean.

How the River Got Its Name

The name "Southwest Branch Saint John River" comes from its parent river, the Saint John River. The words "Southwest Branch" help people know it's one of the main rivers that feed into the larger Saint John River.

Historical Names

When Samuel de Champlain explored the coast of New Brunswick in 1604, he named the main river the Saint John River. This was because he arrived on a day important to a saint in the Christian calendar.

For a long time, the Southwest Branch was also simply called "Saint John River." Old maps and reports from the early 1900s often used this name. For example, the 1914 and 1925 editions of a dictionary of rivers and lakes in Quebec called it "St. John River."

Later maps started adding "West Branch" or "Southwest Branch" to help distinguish it from the main river.

Official Name Change

In 1975, the "Commission de toponymie du Québec" (which is like Quebec's official place-naming board) formally changed the name to Rivière Saint-Jean Sud-Ouest. This made the name official and clear, helping everyone know exactly which river was being talked about.