The Ottawa River has over 50 major dams and 13 reservoirs. It is a highly regulated river. The dams were constructed either as a means of flood control, energy production, or to improve navigation.

A total of 43 hydroelectric generating stations and dams are located in the Ottawa River basin, and these are important for the two provinces’ economies. The generating stations are owned by Ontario Power Generation (a for profit company, formerly Ontario Hydro), or by Hydro Quebec, or by Public Works and Government Services Canada, and one is jointly owned and operated by Ontario Power Generation and Hydro Quebec (Chats Falls, 56 km northwest of Ottawa).

Link to real-time water flow data

Link to real-time water level data

Flood Management

The Ottawa River Regulation Planning Board was established in 1983 by the governments of Canada, Quebec, and Ontario to ensure integrated management of the principal reservoirs of the Ottawa River Basin. The goal of this integrated management approach is to, “provide protection against flooding along the Ottawa River and its tributaries, particularly in the Montreal Region, and at the same time maintain the interests of the various users particularly in hydro-electric energy production.” A secretariat has been established in the Ottawa-Hull area as an "executive arm" of the board, and to provide a coordinating centre for all matters pertaining to management of the basin.

Reservoirs have been built to control water flow in the Ottawa River for aiding navigation, hydroelectric energy production and for flood control. Because of the watershed's size, shape and topography, highly varied meteorological conditions result in equally varied responses in water levels from tributaries. Different times of response of the main tributaries combine to produce two distinct flood peaks, about three weeks apart.

• The first flood peak in the Ottawa River originates from unregulated flows from its southern tributaries and occurs about mid-April.
• The second peak results from a combination of high flows from the tributaries of the north shore together with flows from headwater areas, about three weeks later, and is partially regulated.

While the first peak is generally the lesser of the two, it can cause considerable flood damage since ice is still in the river and ice jams can occur.

There are no simple solutions to the flood problems of the Ottawa River basin. For example, the southern portion of the basin is unregulated and reservoir storage has a limited effect on the first flood peak. The second peak is strongly influenced by reservoir operations. Normal operations at the principal reservoirs can ensure that a significant portion of the spring runoff is stored. This should substantially reduce the magnitude of the second peak.