There are three "Drought Levels" defined in the Ontario Low Water Response. Following are the definitions and the terms and conditions for
each of the three levels.
For each Drought Level, a Threshold is stated - for both streamflow and precipitation - below which the next level is triggered. For streamflow, the Threshold is stated in terms of the percentage that the current flow in a given river or stream is compared to the average in a normal year. For Level 1, the Threshold is 70%; for Level 2, the threshold is 50%; for Level 3, the Threshold is 30%. The flow figure is taken from the lowest of the summer monthly stream flows - that is for July, August and September. For precipitation, the Threshold is based on the percentage of precipitation for the lowest summer month compared to normal.
DROUGHT INFORMATION SHEET
(Note: This information will be posted on the Tay River web site shortly - www.tayriver.org)
1. EXPLANATION OF THE DROUGHT LEVELS
SUMMARY OF THE CONDITIONS FOR THE THREE DROUGHT LEVELS
There are three "Drought Levels" defined in the Ontario Low Water Response. The information below provides details of the terms and conditions for each of the three levels.
For each Drought Level, a threshold is stated, in terms both the volume of the stream flow and the amount of precipitation, below which the next level is triggered. For stream flow, the threshold is stated in terms of the percentage that the present flow in a given river or stream is compared to the average in a normal year. For Level 1, this threshold is 70% - that is, the stream flow is only 70% of what it is in a normal year. For Level 2, the threshold is 50%; for Level 3, the threshold is 30%. The flow figure is taken from the lowest of the summer monthly stream flows - that is for July, August and September.
For precipitation, the threshold is based on the percentage of precipitation for the lowest summer month compared to normal.
The Ontario Low Water Response for 2001 (May 2001)
In addition to the technical data and criteria relating to precipitation and stream flows, the Ontario Low Water Response states that certain other criteria are also factored into local information, such as social, economic and environmental (no examples have been given for these). Any one of these indicators may signal signs of a potential problem. However, the Government states that all of these factors should be considered carefully and become part of the decision making process when declarations of Level conditions are made.
There are three condition levels described in the response plan. These, and the primary actions associated with each, are:
Level I (first indication of potential water supply problems - primarily a warning level)
· MNR (Ministry of Natural resources) receives information/data, analyses of data & calculation of indices (monthly)
· MNR generates Conditions Reports and Maps for distribution
· MNR issues alert notices (when data falls below indicator levels)
· The local Conservation Authority (CA) assesses alert data and confirms a Level 1 condition
· MNR assesses "weeks without rain" on affected watershed
· MNR then provides weekly precipitation and streamflow data
· CA begins to form a local Water Response Team (WRT) initiates meetings/actions
· MNR provides support and information to CAs developing WRTs
· CA/WRT begins to gather database of water users (all sources)
· WRT leads in efforts/encouraging a target of voluntary 10% reduction in water use
Level II (indicates potentially-serious problem - key focus is conservation of water & restrictions on non-essential uses)
· Ontario Water Directors' (OWD) Subcommittee is formed by Province (MNR Chair)
· OWDC Subcommittee meets on regular basis and links with local WRT (Level II)
· WRT targets a further 10% voluntary water use reduction (e.g. contacts key users and enforces water restriction bylaws etc.)
· MNR continues to provide weekly data and month-end data
· WRT increases monitoring and conservation practices
· WRT begins to assess essential and non-essential water use and potential actions which may be required if conservation efforts can not address water supply
· WRT through provincial representatives, links with OWD Subcommittee to discuss status and conditions on the watershed and make recommendations
· OWD Subcommittee in conjunction with WRT assesses and monitors success of Level II efforts and any need to shift to a lower or higher level
Level III (indicates failure of water supply to meet demand - key focus is on restrictions)
· WRT focuses on water allocation since supply does not meet demand at this level
· Actions move from primarily voluntary compliance to regulatory control
· WRT provides detailed updates and recommends water allocations on the watershed to OWDC Subcommittee (municipal bylaws, restrictions and possible revocation of Permits to Take Water are considered)
· Note: If Level III is agreed to, the Province declares it
· Existing legislation is used to implement water allocation decisions
· MNR continues to support local WRTs and OWDC and provide updated data
· OWDC Subcommittee in conjunction with WRT assesses and monitors success of Level II efforts and timing to revert to a lower level
2. STATUS OF THE TAY RIVER AND MISSISSIPPI WATERSHEDS
Water Response Teams have been formed for the Rideau Valley and the Mississippi Valley Conservation areas. These teams include local community representatives as well government agencies and ministries.
The WRTs meet periodically to review the status of the drought for each area. The Rideau Valley CA declared a Level II Drought Condition in their latest meeting - the week of August 20th; the Mississippi CA declared it the previous week.
The WRTs will meet again to monitor developments and consider whether they will recommend to the Province to go to a Level III.
The MOE is responsible for sending out the drought notices and they state that, as part of the Level II declaration, they have sent notices to all the permit holders in the area asking them for voluntary reductions in useage. This is not monitored for compliance.
Under Level III, the permits can be rescinded entirely.
Tay River watershed
The Tay River does not meet the minimum flow trigger level simply because it is a managed stream and Parks Canada have been maintaining a higher flow level on it to supplement the falling Rideau Canal. However, it does meet the precipitation threshold, and is, therefore, included in the Level II Drought advisories.
The organizations that would have/should have received advisories are: OMYA, Links o'Tay; Ducks unlimited;
The stream flow indicates a Level II, and it was declared. It is not yet at a III condition, but is close.
The farmers' especially have been concerned about available water for stock.
The recent rain helped somewhat but the river is falling off again.
The MVCA is developing information for the use by the municipalities in case a Level III is declared. Eg. Assistance that can be provided in hauling water to dry wells.
The organizations that would have received advisories include OMYA (quarry).
Ottawa City, as a member of the Water Response Team, has been slow to agree to moving to the next drought level, because the Ottawa River, their source, has not been providing a problem.