Flood Forecasting & Warning
The melting of winter’s snow along with the new spring rains can create serious flooding and disastrous effects from the devastation caused by flood waters. Forecasting possible flooding, and warning residents along the Mississippi and Carp Rivers and their tributaries of the danger, are key responsibilities of Mississippi Valley Conservation (MVC).

At locations across the watershed, water levels and related information is recorded through an extensive network of stream gauges, staff gauges and snow course sites. These measurements, weather forecasts and radar information on temperature and rainfall predictions, along with historical data, are all taken into consideration when developing a flood forecast. There are 15 stream gauges located throughout the watershed which are directly connected to the MVC office through a telephone link. They are able to send up-to-the-minute recordings of water levels which are used to calculate the flow rate of the water. Staff gauges are also used to record water levels. Staff gauges are similar in appearance to a large metal ruler, these gauges are secured to structures such as bridges or retaining walls. Water levels are read and reported by MVC staff as well as area volunteers. A snow course consists of a series of 10 wooden stakes driven into the ground 30 metres apart, usually in a straight line. The depth of snow, type of crust on the snow and condition of the ground are recorded at each of the stakes. Most importantly, the water content of the snow is calculated based on the weight of the snow in a core sampler.

Accurate flood forecasting and an effective warning system can minimize the risk to human life and property damage that can result from flooding. It is the role of MVC to act as an advisor for watershed municipalities.

Once it has been determined that there is a potential for flooding within the watershed, municipalities are warned. In most instances, MVC is able to provide 48 hours advanced warning, but depending on the specific conditions, forecasts may only be available a few hours in advance of the start of a flood.

Flood advisories are faxed, emailed and/or phoned to the affected municipalities and to newspapers, television and radio stations within the watershed. Updated flood advisories or flood warnings are prepared as conditions demand.

When a severe flood occurs, as was the case in 1998, a Flood Control Centre is established at the MVC office where the municipalities, media and residents can receive up-to-the-minute information on the situation.