Paudash Lake water level variations explained

We’re all wondering what determines the seasonal water levels in Paudash Lake. PLCA reached out to the Crowe Valley Conservation Association (CVCA) for an explanation. We hope you find this information helpful.

Generally speaking, drawdown happens sometime in the fall. On Paudash Lake it usually starts around Sept 12th, depending on lake levels (earlier if the water is high). The Crowe Valley Conservation Authority (CVCA) aim to have the lake down to winter level by the first week in October. They try to get the levels to a lower target level going into the winter to reduce the severity and potential for flooding come spring. 

The process involves removing logs from the Paudash dam. Normally one log is pulled the first week, one log the week after and a third log before the end of September to try and achieve the winter level. The number of logs can also depend on how much rain has fallen. In 2022, three logs were pulled, and the lake was close to winter level by the first week of October. One log was put back in the dam to keep the lake from dropping any lower. The objective is to lower the lake approximately 12 inches to allow for the spring runoff.

The lake level on Nov 3, 2022 was roughly 4 inches over the winter level and has been at this level since October 20th. If large amounts of rainfall occurs, another log may have to be removed to keep the lake close to the winter level.

The timing of the drawdown depends on current and future conditions. Starting with higher water levels will result in an earlier and prolonged draw down. Heavy rains experienced during this time could stall/prolong it further. Then there are certain nuances with each lake. Some lakes have a lower threshold to ensure that water lines will not be affected. With Paudash for example, there is a lower threshold that should not be passed in order to avoid having negative impacts on lake trout spawning. Paudash is one of the first lakes to be drawn down to allow the lake trout to spawn. Lake trout usually spawn in early October in shallow water. If the lake was lowered after the spawn, the eggs could dry up or freeze. The lake may seem lower this year (2022) as the water was higher than the summer level in early September. 

The year 2022, as a whole, was rather dry and this trend continued into early fall. The lakes have approached/reached their target draw down levels without much coaxing. So although CVCA does have a hand in managing water levels, the primary determination of whether levels are high or low, is the conditions dealt by mother nature in a given year. 

Over 30+ years of observations, Paudash fluctuates approximately 75cm from extreme lows (drought scenario) to extreme highs (flooding). 

Paudash Lake is part of the Crowe Valley watershed. The Crowe Valley watershed gets its headwaters near Paudash Lake in Wilberforce, Ontario. From here, many rivers gather momentum and size as they drain south of Marmora, where the Crowe River drains into the Trent River on its journey towards the Bay of Quinte and Lake Ontario.*

*https://www.crowevalley.com/what-is-a-watershed/

Information provided by A. McIntyre and N. McConkey, Crowe Valley Conservation Association CVCA