The Petitcodiac River is a river in south-eastern New Brunswick, Canada. Referred to as the "chocolate river" by local tourist businesses, it is characterized by its brown mud floor and brown waters. The river has a meander length of and is located in 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. Before the construction of a causeway in 1968, the river had one of the world's largest tidal bores, which ranged from in height and moved at . 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, and used it as part of a portage route between Shubenacadie and the village of Petitcodiac, where they had a winter camp. Acadians from Port Royal, Nova Scotia colonised the region in 1698, but were expelled in 1755 during the Seven Years' War. Acadian resistance fighters in Village-des-Blanchard (now Hillsborough) fought under the command of French leader Charles Deschamps de Boishébert in the Battle of Petitcodiac to fend off British troops and suffered the destruction of most of their settlement. The British troops revisited the river three years later and conducted the Petitcodiac River Campaign. In the 1840s, the Greater Moncton area saw a shipbuilding boom, but this was halted following the arrival of the steam train, and forced the town to unincorporate. These changes eventually marginalised the Petitcodiac River. In 1968, a controversial rock-and-earth fill causeway was built 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 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