ChipLakeNEWS InfoSheet

This InfoSheet is number: 1007

Summary: This is a transcription of the information brochure about the St. Croix River Basin put out by the St. Croix Waterway Commission and the International Joint Commission

The St. Croix River runs along 185 km (115 miles) of the international boundary between Canada and the United States. This portion of the boundary lies between Maine and New Brunswick and includes the main stem of the river and its headwaters. The river basin covers an area of about 4,230 sq. km (1,630 sq. miles) making it the fourth largest river basin in New Brunswick and the seventh largest in Maine.

The St. Croix River has always played an important role in the development of this area because the economy is based largely on natural resources and tourism. The river is known for its fisheries and recreational resources as well as being a source of hydro-electric power and municipal and industrial water supply.

As part of the international boundary between Canada and the United States, the St. Croix River is subject to the terms and conditions of the [International] Boundary Waters Treaty.


The purpose of the Boundary Waters Treaty, signed in 1909, is to prevent or resolve disputes over the use of waters shared by the United States and Canada. The International Joint Commission, with members from Canada and the United States, was established by the Treaty and given responsibilities in two general areas:

First, in the absence of a special agreement between the two federal Governments, uses, obstructions or diversions of waters flowing along the boundary that affect the natural levels or flows on the other side of the boundary require the approval of the International Joint Commission. Similar approval is required for works downstream from the border in rivers that flow across the boundary if these works raise levels on the upstream side of the boundary. Projects approved by the commission must be operated in accordance with Commission Orders of Approval.

Second, the Commission can be asked by the Governments of the two countries to investigate and recommend solutions to other problems such as the pollution or apportionment of boundary and transboundary waters.


Because certain dams and other works affecting levels and flows in boundary waters come under the Boundary Waters Treaty, a number of structures in the St. Croix River have required the approval of the International Joint Commission. In 1915, the Commission gave its approval for the construction and operation of the dam at Grand Falls. Similar approvals were given in 1934 for the dam at Milltown; in 1965 for the dam at Vanceboro; and, in 1968 for the dam at Forest City.

St. Croix River water quality issues have also been addressed under the Boundary Waters Treaty. Historically, the St. Croix River was famous for a major Atlantic salmon run. It also served as a recreational resource and as a source of water and hydro-electric power for communities and industries along the river. The combination of dam construction, log driving and waste discharges to the river led to the disappearance of the salmon runs early in this century and diminished the value of the river as a suitable supply of drinking water and its appeal as a recreational resource.

By 1950 the river was severely polluted. Something needed to be done. In 1955, the Governments of Canada and the United States, under the Boundary Waters Treaty asked the International Joint Commission to study and recommend actions for the improvement of the use, conservation regulation of the basin’s water resources.

In a 1959 report to Governments, the Commission made a number of recommendations including water quality objectives that should be met to maintain the river in satisfactory condition. The Governments adopted the water quality objectives for that portion forming the boundary and agreed that pollution abatement measures would be undertaken to meet these objectives.

Much of the work to regulate and clean-up the St. Croix River has been done under the authority or on the advice of the International Joint Commission which relies heavily on an advisory board, the International St. Croix River Board.

Originally, there were two boards established by the IJC, the St. Croix River Board of Control and the Advisory Board on Pollution Control - St. Croix River. The current River Board represents the combination of both prior boards and is made up of equal numbers of Canadian and U.S. members who serve the Commission in their personal and professional capacities rather than as delegates from their primary agencies.


The International St. Croix River Board of Control, consisting of two members, was established by the International Joint Commission in 1915 to oversee the construction and operation of the dam at Grand Falls. Similar responsibilities for the dams at Forest City, Vanceboro and Milltown, constructed for power generation and water storage purposes, and fishways in the boundary waters of the St. Croix system were added later.

The main objective of the Board of Control was to ensure that levels of the lakes and flows in the river, which are controlled by various dams, are maintained within the limits set by the Commission’s Orders of Approval. The Board also conducts annual inspections of the system and reports annually to the Commission on its activities.


The International Joint Commission was requested by the two Governments to maintain continuing surveillance over progress towards compliance with the water quality objectives and established the six member International Advisory Board on Pollution Control - St. Croix River in 1962 for this purpose.

The main objective of the Advisory Board on Pollution Control was to monitor the water quality and advise the Commission on the general state of health of the St. Croix River. In its annual reports to the Commission, the Board provides information on:

1) Progress in pollution control particularly in the area of pulp mill operations.

2) Progress in meeting water quality objectives established by the Commission for the river.

3) Efforts to restore the salmon fishery to the river.

4) Areas where water quality improvements are required, terms of the water quality needs of fish populations, recreational users, industry and local residents.


The water quality of the St. Croix River has improved dramatically in the past twenty years. Salmon have been reintroduced and other migratory fish such as alewives, eels and shad have returned. The river’s water quality is improving and there is a growing number of recreational users. However more remains to be done for the river to reach its full potential and become a wholesome and valuable resource to be shared by all users in Maine and New Brunswick. While resource management is generally the responsibility of the state and provincial governments, the International Joint Commission, through it's River Board, continues to monitor water levels and flows, water quality, pollution abatement efforts and fishery restoration activities along the river in order to make recommendations to Governments on what needs to be done.

Public input to the International Joint Commission’s considerations is welcome. Comments and requests for additional information should be directed to the International Joint Commission at the following addresses:

IJC, 2001 S. Street N.W., Second Floor, Washington D.C. USA 20440 (202)673-6222
IJC, 100 Metcalfe Street, 18th Floor, Ottawa, Ontario Canada K1P-5M1 (613)995-2984

ChipLakeNEWS Pages: List of InfoSheetsMapsHome Page