The following statement summarises current conditions in the Tay waterway between Bobs Lake and Port Elmsley.
Tay Waterway Water Level Update - March 31, 2022
As of Wednesday, March 30, water levels along the Tay Waterway are generally at a normal high level for the spring
'freshet' period. This is expected to continue, although
there is potential for increased precipitation in early April.
Christie Lake Association has provided the following report based on Parks Canada's update of March 29th.
"The Snowpack for the 2021/22 winter season was average and, due to recent spring conditions, approximately 80% of the snowpack in the Tay River drainage area has melted. The rapid melt has resulted in high water levels on Bobs Lake and Christie Lake; however, flooding conditions are not forecast.
In anticipation of additional moisture in the form of rain and/or snow
through the first half of April, Parks Canada will be increasing the flow from
Bobs Lake. Parks Canada has indicated that they see no reason that flood levels
on Christie Lake will be reached and that they will continually monitor the
water levels on Christie Lake throughout the 2022 Spring Freshet. They will
contact the downstream stakeholders should conditions change."
The foregoing could affect levels in the mid-waterway area (Christie Lake to Glen Tay).
A positive note - Eagle Lake level peaked on March 28 and started to drop.
Water levels at Perth are at normal high freshet level and have decreased since March 26th. As in other parts of the waterway, this is earlier than the usual spring peak. Levels above Perth to Glen Tay have been very high, possibly due to ice build-up, but have been dropping since over the past two days.
Port Elmsley levels were increasing over in the past week, due to high water upstream of the Beveridge Dam in the Tay Canal sector. The level at Port Elmsley is presently (March 30th) amongst the highest of the past three years, however, as these were not peak years, there is still room for increase. This is being monitored.
For current water levels:
Tay Waterway: A 2021 Review
Over the past 12 months, water levels along the Tay waterway experienced substantial, and often unseasonal, fluctuations, which some long-term residents have described as unprecedented.
For the first eight months of January to August 2021, water levels from Bobs Lake to Port Elmsley were extremely low. Most prominently, Christie Lake was consistently near, and often below, its minimum historic low level, and Perth experienced periods when the flow was as low as 50% under normal. The initial cause was the low snowpack of the 2020/2021 winter, followed by below normal precipitation in the spring. During this period, the flow from Bobs Lake Dam was not increased, and the lake level was maintained at close to its historic average.
In early August, the flow from Bobs Lake Dam was suddenly doubled, which caught the attention of downstream residents when some docks ended up under water. This happened at a time when the level in the Rideau Canal was dropping, and presumably additional water was needed to maintain the canal's 5-foot target draft.
A quick turnaround in the fall, beginning in October, brought extremely high water levels, which were maintained through December in most parts of the waterway. In November, Christie Lake was close to its Historic High. In Perth, high rainfall in December raised the flow to 100% over average.
Since then, entering the New Year with the winter freeze, levels have dropped substantially - in some areas, to below average.
The foregoing level fluctuations would not be significant if more were known about where climate change is taking us. To summarise, for most of 2021, Parks Canada maintained the Bobs Lake level at close to its Historic Average. Because there have been major dry and wet spells affecting Christie Lake and the rest of the waterway, this can only happen if a priority is being given to maintaining levels at Bobs Lake, to feed the Rideau Canal system, rather than to care for the 45 km waterway as a whole. Of note, this was also the case in late 2020, when the waterway was high, while Bobs Lake was maintained at a normal level. This situation was certainly exacerbated by Parks Canada withdrawing daily public access to Bobs Lake flow data.
Information and updates on the Tay Net Program may be seen on the website at
November 28, 2021
Following unusually high water since late October, at some sectors of the waterway, levels started to drop in mid-late November. However, levels and flow are still well above average throughout the waterway, with the sole exception of Bobs Lake.
Christie Lake is presently just below its Historic High. Levels between Christie Lake and Perth are the highest since last winter. Flow at Perth is 18% over its Historic Average, having dropped from a November 19 peak. Beveridge Lock level is currently close to its Historic High, as the upper watershed excess passes through it. As this excess is mainly sent through to Port Elmsley, the level there, on November 20th, was its highest since last January.
For most of this year, Parks Canada has maintained the Bobs Lake level at close to its Historic Average. Because there have been major dry and wet spells, this can only happen if a priority is being given to maintaining levels at Bobs Lake, rather than to care for the 45 km waterway as a whole. Over the past year, Christie Lake and the waterway have experienced both serious highs and lows. The situation has been exacerbated by Parks Canada withdrawing daily public access to Bobs Lake flow data.
August 13, 2021
Water Levels and Flow along the Tay waterway increased substantially between August 6 and 7, due to a large increase in flow from the Bobs Lake (Bolingbroke) Dam.
There has not been a notice from Parks Canada, who manage the dam, regarding the amount of the increased flow. Water levels in Bobs Lake, above the dam, have been normal for several months, but the flow had not been increased to address the extremely low levels that have existed since February along the rest of the Tay waterway.
For some months, the flow at Perth has varied between 25% and 50% of normal historic flow. Christie Lake, just downstream from Bobs Lake dam, had been close to, and often under, its minimum historic level.
As a result of the increased flow, water levels on the Tay in many areas have reached historic average for the first time this year. Perth flow increased to over the historic average, as of this date.
Parks Canada have not announced the reason for the sudden increase. However, streamflow charts for some parts of the Rideau downstream, including Merrickville, had recently showed water
levels below average, indicating a need in the Rideau Canal system.
May 31, 2021
Water levels along the Tay waterway have been substantially below historic levels since late January
- and, in most sectors, close to their minimum historic levels for this time of year. This would indicate that the waterway is not well-situated to meet the normally dry summer season ahead, without considerable precipitation, which has been well below average this year to date.
Sectors displaying the most apparent low levels are Christie Lake and the Town of Perth. These are also the most vulnerable to significant level changes
- the lake because of cottage properties and local roads and the town for its dependence on the river for water supply.
This is a considerable turnaround from the exceptionally high watershed levels late last year. At that time, Christie Lake was above its historic average high, while Parks Canada was allowing Bobs Lake to remain at its normal level.
In May 2021, the two waterway sectors located above Parks Canada dams (Bobs Lake and Beveridge Lock Dam) are being held at close to their normal historic levels, despite the need for water downstream. Levels along the Tay River between Christie Lake and Perth, and Port Elmsley bridge, have been unusually low for this time of year. This has potential to impact the general environment, including wildlife habitat, in addition to limiting use by residents - and even some recreation access, at a time when encouraging
'getting out' would seem a priority for government.
Tay Waterway Readings by Location, Late May 2021, including Tay Net Watchers
Electronic Water Level or Flow Gauge Sites:
Bobs Lake Dam, Bolingbroke - close to historic average level; slight trend down
Christie Lake exit - close to the minimum historic average level, trending down
Perth Haggart Island - 70% below historic average flow
Beveridge Locks - is being maintained at historic average level
Tay Net Monitoring Sites - Low to extremely low levels: Bathurst Concession Two Bridge; Bowes Road Bridge; 471 Christie Lake Road Bridge; Rogers Road Bridge; Beckwith Bridge; Craig Street Bridge; Port Elmsley Bridge.
December 14, 2020
Water levels in the Tay waterway between Bobs Lake and Port Elmsley have been unusually high due to rain in the Fall and then melting snow in early December. The obvious exception is Bobs Lake, where levels have been held consistently at ‘normal’ (that is, the historic average) since July, despite increased flow from one main source, Eagle Lake.
Christie Lake on the other hand, just below Bobs Lake, has been at the historic maximum levels since August, dipping only briefly in November before returning to maximum this month. Immediately downstream from there, levels are close to the highs experienced last spring (and, also, the unusual January flood). This is the same just above Perth.
The flow into Perth has usually been above historic average since August, and on December 13th was 40% above historic average. This should reduce with the colder weather arriving in mid-December, however, as noted above, there remains a substantial amount of water upstream.
Below Perth, Port Elmsley level (124.11m) is the highest since spring (124.37m) and last January flood (124.33m) Note: the readings are metres above sea level.
September 1, 2020
Following the major rainfall on August 29th, water levels and flow in most areas of the waterway again increased, with the biggest impact at Perth (flow increased from 6.7cms to over 9. The historic average is 4.9). Bobs Lake level moved above its historic average but is well below its 'maximum'. Eagle Lake had increased substantially but is trending down. Christie Lake continues to increase, above its maximum. Downstream from Christie Lake, including Perth and below, levels remain high; at many locations just below spring peaks.
August 28, 2020
As anticipated, water levels and flow along the waterway have continued to drop following the substantial rain and resultant increases earlier in August. In particular, Bobs Lake and Christie Lake have dropped considerably, but Christie Lake still remains above its historic maximum level. The level at Bobs Lake is slightly above the historic average. The flow at Perth is still high, at 6.8 cubic metres per second (cms), which is 50% above the historic average of 4.5 cms.
In the past, water levels along the Tay waterway have dropped continuously from early fall.
For current and recent water levels and flows at selected sites on the waterway, see the links to electronic gauges below.
* Qualification of Statements:
This statement is based on information provided by the association's network of 'Tay Net' reporters and by data on the
Rideau Valley Conservation Authority
Because online flow data was withdrawn for the Bolingbroke Dam in 2018 by Parks Canada, and waterway conditions can change rapidly, the association is unable to take responsibility for the accuracy of the data and statements.
Click here for a description of the Tay Net Waterway Reporting Program.