Mississippi WatershedOver the past number of years, the Mississippi watershed has been experiencing more severe weather events, whether due to global climate change or to the natural long-term fluctuations in climate and weather. These unpredictable severe rainfalls and droughts make the job of managing water levels that much more difficult. The watershed historically receives approximately 870 mm of precipitation annually, and it loses about 530 mm to evaporation and transpiration, leaving only 340 mm to re-supply the round water, and fill the upper lakes.

Mississippi Valley Conservation collects rain data in heated tipping buckets at all of the eight Water Survey Canada stream flow gauges in the Mississippi Watershed. Manual gauges are operated by volunteer observers following Environment Canada protocol.

Mississippi Valley Conservation operates 14 snow sites in the Mississippi Watershed, where snow pack data is collected.

Adapted from MVC: Mississippi River Water Management Plan Final Report

Mississippi WatershedHistorically, the maximum flows and levels occur in late March or early April, however, recent trends have shown peak flows can occur at any time of the year. The highest recorded floods on the Mississippi River system occurred in April 1998 as a result of the ice storm, combined with a significant snow pack, an unusually warm 4 day period and significant rainfall.

Mississippi WatershedThere are approximately 269 lakes within the watershed, the largest lakes being Mazinaw, Kashwakamak, Big Gull, Mississagagon, Buckshot, Crotch, Dalhousie, Sharbot, Bennett,  Palmerston, Canonto, Mississippi and Clayton Lakes.  The western portion of the watershed contains the bulk of these lakes with the most significant storage lakes being Shabomeka, Mazinaw, Kashwakamak, Mississagagon, Big Gull and Crotc

Traditionally stormwater management has been involved in controlling the flow of water from peak flow events. Stormwater management has evolved into a more integrated approach that includes development policies, environmental goals, water quality and other aspects. Stormwater management is related to watershed and subwatershed planning which investigate the natural functions and features of the watershed.

Mississippi WatershedShoreline erosion is a problem which can be caused by shoreline development, flooding, clearing of vegetation. Unstable shorelines can be easily washed away. It is important to maintain a ‘buffer’ of vegetation along river and lake shorelines in order to reduce erosion.

Click on the map image to see areas in your watershed that are vulnerable to erosion.

Mississippi WatershedMunicipal and Private Water Taking

Water use in the watershed is a mixture of drinking water, recreational, ecological, agricultural and industrial uses. Within Ontario, any use of more than 50,000 L/day requires a permit to take water (PTTW). The PTTW program is operated and enforced by the Ministry of the Environment (MOE). The MOE maintains a PTTW database which lists all large water users and permitted water takings. It should be noted that the current PTTW database is only the maximum daily permitted water withdrawal amount and not the actually daily usage. Permit holders are now required to document their actual water takings and future iterations of the PTTW database will improve the knowledge of the actual usage of water.

There are a number of water-taking permits issued for the Mississippi River. Of these, only four result in a direct extraction of approximately 14,000 cubic metres of water per day (m3/d), which is equivalent to 0.16 cubic metres per second (cms). The most notable of these is for the municipal water supply at Carleton Place, which has a maximum taking of water at 12,000 cubic metres of water per day (m3/d).

Hydro-electric Generation

There are a total of 5 hydro electric generating stations along the Mississippi River, these being High Falls Generating Station (owned by Ontario Power Generation), the Appleton  and Galetta Generating Stations (owned by Canadian Hydro Developers Inc.), the Enerdu Generating Station (owned by Enerdu Power Systems Ltd.) and the Almonte Generating Station (owned by the Mississippi River Power Corporation).  The total installed capacity of these 5 hydro-electric stations is 8 megawatts with the average annual production based on current water flows being roughly half the installed capacity.

Adapted from MVC: Mississippi River Water Management Plan Final Report

Get involved in one of the many events taking place in the Mississippi Watershed! Find more information about water flow programs happening in the Mississippi watershed.

Learn about volunteer opportunities at the MVC website