November, 2026 

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The chart above tells the story of two very different summers on Pike Lake. In 2025, hot, dry conditions caused water levels to drop significantly. This summer, frequent rain and thunderstorms brought much higher levels. News reports highlighted the record-setting drought across much of Eastern Ontario in 2025, followed by Ottawa’s wettest July on record in 2026.

 

Pike Lake responds to both nature and water management. Rainfall, drought and seasonal dam operations all influence water levels, with impacts on our shorelines, runoff, water temperatures, aquatic plants and wildlife. Comparing these two summers is a useful reminder of how much conditions can vary from year to year, and why understanding these changes helps us care for our lake.

 

What can we learn from this summer’s water levels?

 

Following substantial rainfall in August 2026, the Rideau Valley Conservation Authority (RVCA) reported elevated water levels and flows in parts of the Rideau Valley watershed. Although flooding was not anticipated at the time, residents were cautioned about fast-moving water and unstable banks.

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Our Pike Lake chart provides a local picture of these changing conditions. While it records water levels on our lake, watershed reports help explain the broader weather patterns affecting our region.

 

Read the RVCA’s August 10, 2026 watershed update for more information.

 

How does the Grants Creek Dam fit in?

 

The Grants Creek Dam follows a “rule curve”, a chart of target water levels throughout the year, designed to mimic the seasonal pattern of a natural lake, with higher levels in spring and lower levels heading into winter. Managing the dam involves balancing Pike Lake’s seasonal water levels with the importance of maintaining downstream flow in support of aquatic habitats and the natural functioning of the creek and local ecosystem.

 

In spring, stop-logs are adjusted to help manage rising water from snowmelt. In a typical year, the planned base flow of 10 cubic feet per second (cfs) into Grants Creek helps lower the lake over the summer. Heavy rainfall can mean additional adjustments are needed. The heavy rain in early August pushed Pike Lake above its operating limit, prompting the Ministry of Natural Resources (MNR) to remove some of the smaller stop-logs. Another log was removed in mid-September, with the remaining logs removed at the end of September. The resulting decline was intentional and consistent with the operating plan, bringing the lake closer to its winter target.

 

Operating levels are measured above the dam’s concrete sill:

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• Summer target: 0.98 metres

• Winter target: 0.61 metres

• Upper operating limit: 1.04 metres — just 6 cm above the summer target

 

For waterfront residents both high and low water bring challenges. Heavy rainfall and high water can increase shoreline erosion and runoff, while prolonged dry conditions can affect water supplies, aquatic habitats and wetlands. A few practical steps can help protect your property and our lake:

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• Keep your shoreline green. Natural vegetation helps slow runoff and hold soil in place.

• Check your waterfront after heavy rain. Look for erosion, unstable banks and changes around docks or other structures.

• Use water wisely during dry spells. This is especially important if your property relies on a private well.

• Stay informed. Follow local water safety and low-water advisories.

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Want to learn more?

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• RVCA – Streamflow and Water Levels: Explore available streamflow, water-level and weather-monitoring data.

• RVCA – Current Watershed Conditions: Check current watershed statements and water safety information.

• FOCA – Water Levels: Highs and Lows: Find practical advice on high water, drought, flooding and waterfront property preparedness.

 

For questions about Grants Creek Dam operations, contact the Kemptville–Kingston Ministry of Natural Resources office at kemptville-kingston.mnrf@ontario.ca.