| Southeast Upsalquitch River | |
| Subdivision Type1: | Country |
| Subdivision Name1: | Canada |
| Source1 Location: | Upsalquitch Lake, Northumberland County, New Brunswick |
| Source1 Coordinates: | 47.4847°N -66.4969°W |
| Source1 Elevation: | 251m (823feet) |
| Mouth Location: | Addington Parish, Restigouche County, New Brunswick |
| Mouth Coordinates: | 47.6719°N -66.7078°W |
| Mouth Elevation: | 75m (246feet) |
| Length: | 39.6km (24.6miles) |
| Tributaries Left: | (from the confluence) Caribou Brook, Ferguson Brook, Nine Mile Brook, Oxbow Brook, McCormack Brook, Ramsay Brook, Simpsons Brook |
| Tributaries Right: | (from the confluence) Levesque Gulch, Little Popetogan Brook, Basket Brook, Little Southeast Upsalquitch River, England Brook, Meadow Brook, Murray Brook, Eithteen Mile Brook, Cook Savoie Gulch |
The Southeast Upsalquitch River is an eastern tributary of the Upsalquitch River in the northwest of New Brunswick, Canada, flowing through Northumberland County and Balmoral Parish and Addington Parish in Restigouche County.
In its course towards the northwest, the Southeast Upsalquitch River runs through the Naturalists Mountains and passes to the northeast of Caribou Mountain.
The Southeast Upsalquitch River originates at the mouth of Upsalquitch Lake (length: 1.6km (01miles); height: 251m (823feet)), in the Northumberland County. This lake is located in a small north-south valley that extends to the south on the other hydrographic side to Popple Depot, located on the north bank of the Nepisiguit River. Upsalquitch Lake is embedded in the Naturalists Mountains.
The mouth of Lake Upsalquitch is located in a forested area:
From the outlet of Lake Upsalquitch, the Southeast Upsalquitch River flows 39.6km (24.6miles) in a little valley surrounded by high mountains, in the following segments:
Upper course of the river (segment of 19.7km (12.2miles))
Lower course of the river (segment of 19.9km (12.4miles))
The Southeast Upsalquitch River empties into a river curve on the east bank of the Upsalquitch River. The mouth of the Southeast Upsalquitch River is 29.3km (18.2miles) southeast of the mouth of the Upsalquitch River.
Upsalquitch Lake has a subarctic climate (Dfc). Summers are typically rainy and mild with only a handful of warm days and cool nighttime temperatures. Winters are some of the longest, coldest and snowiest in New Brunswick, with annual snowfall averaging 130 inches (330 cm). Winters can begin towards the end of October and last well into April.[2] [3]