The Authority can issue three flood messages:

To see the current status, click here

A FLOOD WARNING - a notice declaring that flooding is imminent and requires action by municipalities, emergency services and residents

A FLOOD ADVISORY - serves to notify municipal flood co-ordinators and other primary contacts that the potential for flooding exists in the near future

A WATERCOURSE SAFETY OR WATERSHED CONDITIONS BULLETIN - a general notice of conditions that pose a risk to personal safety or may report general watershed conditions. Flood Safety Bulletins may be posted when streams are flowing near bankfull levels, when ice conditions are unsafe or when stream banks are soft or slippery.

Click to see Flood Forecast Centre, Procedure During Flood Event Flow Chart.

To find out if a flood message has been issued please consult the following:

1. Radio, Television and daily print media will air flood messages
2. Go to the home page of the Nottawasaga Valley Conservation Authority and click on FLOOD STATUS. Check back often as messages can change without notice
3. Dial the Authority flood information line at 705-424-1479 extension 702
4. Contact your local municipality.

If you have an urgent flooding concern, please contact your municipality. If you are unable to reach someone, please contact our Flood Duty Officer at 705-309-0405 and we will attempt to contact the municipality on your behalf.

Emergencies should always be called in to 911 service, or to the appropriate emergency service number for your location.

Roles and Responsibilities of Participating Organizations
A number of agencies, municipal departments and individuals bear responsibility, in varying degrees, for the efficiency of the flood warning system. They are: 

Ontario Provincial Police through the District Headquarters in Orillia operates a communications link with municipal officials and enforcement departments which complements the system operated by the NVCA. During a flood emergency, the OPP is responsible for carrying out rescue operations, obtaining necessary medical aid and maintaining law and order within affected areas.
Radio, Television and Newsprint Media Services operating within the NVCA's jurisdiction provide the primary means of relaying flood related information to affected residents.
The Ministry of Natural Resources maintains the provincial streamflow forecast centre in Peterborough, which advises the NVCA of potential storm-producing weather patterns that may affect watershed flooding conditions. Through the local Flood Response Coordinator (Midhurst District Manager for the Nottawasaga Watershed), the Ministry directs and delivers the provincial response to a municipal request for assistance, when a flood emergency has escalated beyond the capabilities of local resources.
Municipal Officials are initially responsible for the welfare and protection of their residents from floods. It is crucial that each municipality establish an all risk emergency plan with specific reference to flooding, compatible with those of other agencies, which will assist officials with the orderly implementation of local resources. NVCA assistance in the development of the flooding component of such plans will be available upon request.
Municipal Residents have an obligation to safeguard themselves and their belongings to the best of their abilities after being duly warned of flood danger. Residents should prepare their own flood emergency plan including an evacuation plan and should know where the flood susceptible areas in their region are located. Residents are responsible for obeying municipal and other agencies warnings, instructions and directions as they are received.

How does the Authority Forecast a Flood?
Authority staff perform a "Daily Planning Cycle" for flood forecasting and warning. Information on predicted weather is collected from various sources (Internet, Environment Canada, MNR Streamflow Forecast Centre) and compared to current watershed conditions. The cycle provides base information for staff on the conditions of the watershed.

Data is collected from a stream flow stations monitoring network using a specialized software program. This program telephones the gauges, downloads stream level, rainfall or temperature data, and processes and stores the data in a database. The level information is used to calculate the current flow within the watercourse using level/flow relationships (rating curves). The flow value is then compared with historic flow records to determine the current status of the watershed with respect to flood or low water applications.

Flooding FAQ's

What's New?
Authority staff are endeavoring to predict river levels using mathematical flood forecasting models and are developing the 'Hydrological Simulatoin Program-Fortran (HSPF) model. The model uses forecasted weather and current watershed conditions to estimate water levels in a particular location, and is currently being calibrated for use in the Nottawasaga Valley watershed.

Authority staff are endeavoring to predict river levels using mathematical flood forecasting models and are developing the 'Hydrological Simulatoin Program-Fortran (HSPF) model. The model uses forecasted weather and current watershed conditions to estimate water levels in a particular location, and is currently being calibrated for use in the Nottawasaga Valley watershed.

Characteristics of the Nottawasaga Watershed for a Widespread Rainfall/Snowmelt Event
Heavy rain or snowmelt floods the river systems in the south half of the watershed, which eventually drains through the Minesing Wetlands prior to entering the lower reach of the Nottawasaga River upstream of Wasaga Beach. The Wetlands is like a huge sponge which fills with vast quantities of water and releases it at a much slower rate.

In the upper reaches of the Nottawasaga River, a flood peak (highest point in the flood) can pass by a location very quickly - whereas downstream of the wetlands it can take weeks. The shape of the peak in the upper portions is sharp and is reduced and broadened before entering Wasaga. As many homes, roads and cottages are present in the floodplain in Wasaga Beach, without the beneficial and moderating impact of Minesing Wetlands, the annual damage in the Beach might be quite costly.

The water fills Minesing Wetlands for two reasons:

1. The wetlands is a vast, flat area, where floodwater in excess of the channel capacity can spread out to great distances. River levees have built up on the Nottawasaga River and are much higher than the flat overbank areas. These levees are overtopped and floodwater spills into the wide overbank areas and are stored. The levees prevent the water from coming back into the channel.
2. At the end of the wetlands is a feature called the Edenvale Morraine, which is like the stopper in your bathtub. It is quite small compared to the floodplain in the wetlansd, and acts as the bottleneck to the entire system.