South Run at Lake Mercer
Flood levels
Official flood levels at this gauge: action stage begins at 220.0 ft; minor flooding begins at 240.0 ft; moderate flooding begins at 248.0 ft.
| Action stage | 220.0 ft |
|---|---|
| Minor flooding | 240.0 ft |
| Moderate flooding | 248.0 ft |
Highest recorded crests
- 228.0 ft on Sep 9, 2011 (historic crest)
What the water does
National Weather Service impact statements for this gauge, in the Weather Service's own words.
| 220.0 ft | Backwater lake flooding likely starts to affect canoe ramps, trails, and gated service roads in Lake Mercer Park. |
|---|---|
| 234.0 ft | Dam's auxiliary spillway is activated which may cause swift water to flood nearby downstream trails. |
| 240.0 ft | Lake water may approach a cul-de-sac on Wagon Trail Lane. All trails in Lake Mercer Park are likely flooded. |
| 245.0 ft | Lake water may approach the back of some homes, especially along Golden Sunset Lane, Daum Court, and Galla Knoll Circle. |
| 248.0 ft | Flooding of structures is possible if water enters lower levels of homes along Golden Sunet Lane, Daum Court, and Galla Knoll Circle. |
| 252.0 ft | Water starts to overtop the Lake Mercer Dam. |
Forecast office: NWS Sterling · River Forecast Center: Middle Atlantic River Forecast Center.
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Nearby stations and gauges
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- Unnamed Tributary at Lake Braddock in Burke NWS gauge · 4.4 mi