The Petitcodiac River () is a river located in south-eastern New Brunswick, Canada. Local tourist businesses often refer to it as the "chocolate river" due to its distinctive brown mud floor and brown waters. Stretching across a meander length of , the river traverses Westmorland, Albert, and Kings counties, draining a watershed area of about . The watershed features valleys, ridges, and rolling hills, and is home to a diverse population of terrestrial and aquatic species. Ten named tributaries join the river in its course toward its mouth in Shepody Bay. Prior to the construction of a causeway in 1968, the Petitcodiac River had one of the world's largest tidal bores, which ranged from in height and moved at speeds of . With the opening of the causeway gates in April 2010, the river is flushing itself of ocean silts, and the bore is returning to its former size.
The Mi'kmaq were the first to settle near the river, who used it as part of a portage route between Shubenacadie and the village of Petitcodiac, where they had a winter camp. In 1698, the region was colonized by Acadians from Port Royal, Nova Scotia; however, they were later expelled in 1755 during the Seven Years' War. During this period, Acadian resistance fighters based in Village-des-Blanchard (now Hillsborough) fought under the command of French leader Charles Deschamps de Boishébert in the Battle of Petitcodiac, attempting to repel British troops but ultimately suffering the destruction of most of their settlement. Three years later, British troops returned to the river and launched the Petitcodiac River Campaign. In the 1840s, the Greater Moncton area experienced a shipbuilding boom, which was halted following the arrival of the steam train, leading to the town's de-incorporation. These changes gradually marginalized the Petitcodiac River.
In 1968, a controversial rock-and-earth fill causeway was constructed between Moncton and Riverview to prevent agricultural flooding and to carry a crossing between the two communities. The causeway caused many problems for the river and its surrounding ecosystem. An estimated 10 million cubic metres (13 million cubic yards) of silt was deposited in the 4.7 km (2.9 mi) of river downstream from the causeway in the first three years following construction. The causeway restricted the movement of fish and reduced the region's salmon catches by 82 percent. Water quality has also dropped thanks to industrial expansion around the area. In 2003, Earthwild International designated the Petitcodiac River as the most endangered river in Canada because of these problems. On 14 April 2010, the causeway's gates were opened permanently as part of a $68 million three-phase project designed to restore the river. The causeway was replaced with a bridge, completed in September 2021.
Etymology A commonly held belief suggests that the name "Petitcodiac" originates from the French term "petit coude," meaning "little elbow." However, the actual derivation of the name is rooted in an indigenous word, likely from Wolastoqey or possibly Mi'kmaq language. According to Wolastoqey Elder and linguist Dr. Peter Paul of Woodstock Reserve, the name refers to a wall of water rushing in: "now they call that petakuyak. [It] means 'sound of thunder,' well, the rush of water coming in like a thunderstorm."Dr. Peter Paul interview with anthropologist Harald E.L. Prins and Bunny McBride, Hallowell, Maine, 12/02/1988, in In Memoriam: Peter Lewis Paul, 1902-1989, edited by K. Teeter, 19-21. Hull:Canadian Museum of Civilization, Canadian Ethnology Service. Mercury Series Paper 26, 1993. If the term has a Mi'kmaq origin, it could be linked to "Petkootkweăk," meaning "the river that bends like a bow", possibly a reference to the river's right angle bend near Moncton. The Acadians adapted the name to Petcoudiac or Petitcoudiac, which was later modified to Petitcodiac by British settlers.
The river gained the nickname "Chocolate River" due to its heavy sedimentation, resulting in a distinctive brown tint. With the construction of the Petitcodiac River Causeway, an additional of sediment began to accumulate in the 4.7 km (2.9 mi) stretch downstream from the causeway.
Geography
Course
The river measures about from its source near Three Rivers to its mouth at Shepody Bay; its source derives from the confluence of the Anagance and North rivers in western Westmorland County.Watershed Alliance 2009, p. 49 The Anagance River arises from its tributaries, Hayward Brook and Holmes Brook, and drains from the south-east of the Petitcodiac River, while the North River drains from the north. From the confluence, the river passes under the bridge on Route 106 in Petitcodiac; the road then follows the river to Moncton on the left side of the river. Route 1 crosses the river a few kilometres downstream to join Trans-Canada Highway 2. The community of River Glade precedes Petitcodiac River's right tributary, Pollett River, with a watershed of . As the waterway runs past Salisbury, its final major right tributary,Riverkeeper 2000, p. 51 Little River (formerly known as Coverdale River), joins it. Little River's watershed is . The river passes Coverdale and is joined by Turtle Creek before widening as it approaches Moncton.
The causeway, built in 1968, formed a wall blocking all but of water as the river flowed downstream toward the Gunningsville Bridge. Before the causeway's construction, the river's area would expand through Moncton, attaining a width of 1.6 km (one mile). A series of banks to both sides precede the 90-degree turn to the south, a feature that gave Moncton its original name, Le Coude (The Elbow). The river passes Dieppe on its eastern side and Hillsborough on its western side before it approaches its mouth.
The Memramcook River, which has a watershed area of , joins the Petitcodiac River near its mouth. The Petitcodiac River then widens and drains into Shepody Bay, where there is a wetland. Once past the Hopewell Rocks, Shepody Bay merges with the Cumberland Basin, which runs south-west toward Chignecto Bay. Chignecto Bay drains into the Bay of Fundy, which flows into the Gulf of Maine, which proceeds south-east into the Atlantic Ocean through the Northeast Channel.
Watershed The Petitcodiac River watershed is about . The average yearly precipitation in the watershed is , with average temperatures of in the summer and in the winter. The watershed is located in the Kings, Westmorland, and Albert counties in south-east New Brunswick, with some of it crossing into the Caledonian Highlands to the south-east. It borders the Bay of Fundy and three other designated watersheds in the province: the lower Saint John River to the north-west, the Shediac Bay to the north-east, and the Kennebecasis River to the south. Although the Petitcodiac River's watershed is geographically distinct from that of the nearby Memramcook River, some groups merge the two for categorisation purposes.
The area has been occupied by Europeans since the late 17th century. Moncton's population has grown rapidly since the 19th century, rising from fewer than 100 people in 1825, to over 15,000 people in 1917, and to 126,000 people in 2006.Watershed Alliance 2006, p. 1 In spite of this growth, most of the area remains relatively undisturbed: 80 percent of the watershed is covered with forest, a tenth is used for agriculture and three percent is occupied by wetlands. Only four percent of the area is used for commercial, residential, or private usage. Nevertheless, the Petitcodiac Watershed Monitoring Group noted in 2001 that this growth is one of the main factors for the ongoing "environmental degradation" of the river.PWMG 2001, p. 25
Hydrology
Water quality
The Petitcodiac River was listed in 2003 as the most endangered river in Canada by Earthwild International, and was listed second, behind Quebec's Rupert River, in 2002. The causeway was cited as one of the major factors behind the river's degraded health. The Canadian Council of Ministers of the Environment's Water Quality Index gave two study sites an "excellent" rating, 20 sites a "good" rating, 27 sites a "fair" rating, and five sites a "marginal" rating.
Since 1999, the Petitcodiac Watershed Alliance (known as the Petitcodiac Watershed Monitoring Group at the time) has collected water samples from May to October to study bacteria, nutrient, pH, dissolved oxygen (DO), and sediment levels.Watershed Alliance 2009, p. 1 Two sampling sites, one upstream from the causeway and one downstream, were used during the 2009 study.Watershed Alliance 2009, p. 49. The river had an average temperature of in August at the upstream location, in contrast to the average of at the same site over the total period of the study.Watershed Alliance 2009, pp. 50–51Watershed Alliance 2009, p. 9 E. coli levels were high upstream, and above recreationally safe levels downstream in June, July, and August. Nitrates and phosphates failed to meet the safe quality threshold on occasion. A publication by the New Brunswick Department of Environment in 2007 showed that the watershed did not meet the quality guidelines for E. coli in 10 percent of samples, for dissolved oxygen in 5 percent of samples, and pH in 3 percent of samples; in contrast, the river was always within safe nitrate levels.
During their 2001 study, the Petitcodiac Watershed Alliance noted the effects of agriculture on the river's water quality, and recommended to work with local farmers to install cattle fencing around streams which run through their properties, and "eventually phase out" cosmetic pesticide usage.PWMG 2001, p. 45–46 The Petitcodiac Riverkeeper holds a stronger position on the issue: the organisation notes that pesticides "find their way into the surface and ground water by leaching into the soil or as part of stormwater runoff." They request that, while measures have been taken in 2009 by the provincial government to regulate cosmetic pesticide usage, the province must forbid its usage altogether and require chemical manufacturers to disclose health warnings and all ingredients on labels.Riverkeeper 2010, pp. 13–14 The New Brunswick Department of Environment also warned of the erosion caused by the removal of the river's riparian zones, which is a common "land use practice".
Although mining around the area essentially stopped with the closure of the gypsum mines in 1982, uranium mining has surfaced as a potential problem for the river.Riverkeeper 2010, pp. 14–15 The province was the subject of a controversy in 2007 when it gave Vale Limited (formerly known as CVRD Inco) the right to mine for uranium at Turtle Creek, where the Greater Moncton water reservoir is maintained. Environmentalists warned of the dangers related to the move, fearing that contaminants could be pushed into the surrounding water. The Petitcodiac Riverkeeper also noted uranium mining's "irreversible effects to the health of ecosystems, watersheds, wildlife, agriculture, recreation, and public health", and joined 30 other environmental groups in asking the provincial government to establish a ban on the act. The province would later restrict uranium mining to from residential areas and ban it from protected drinking water areas. Another controversy in 2006 involved exploration for oil and gas deposits in the same area, but access was blocked by the municipal government.