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Current Conditions Yearly Table View

Select a Year, Sampling Location, and Parameter:

2025 Chesapeake Bay Mainstem - Bottom Dissolved Oxygen (mg/L)

Click on hyperlinked stations to view charts of water quality trends.

Stations Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
CB1.0 - Susquehanna River 14.1 14.2 12.9 10.7 -
CB1.1 - Susquehanna River - - 11.1 11.1 7.6
CB2.1 - Turkey Point - 13.9 11.1 10.3 7.9
CB2.2 - Still Pond - 13.4 10.1 7.9 6.8
CB3.1 - Gunpowder Neck - 12 8.5 5.7 5.6
CB3.2 - Swan Point - 11.2 8.6 6.6 5.1
CB3.3W - Bay Bridge (NW) 11.1 6.9 9.7
CB3.3E - Bay Bridge (NE) 11.6 8.2 9.9
CB3.3C - Bay Bridge 9.7 10 10.4 6.8 2.4
CB4.1C - Kent Point (SW) 9.9 10.2 10.8 7.1 2.2
CB4.1E - Kent Point (S) 10.8 7.3 3.7
CB4.1W - Horseshoe Point 11.3 9.2 9.4
CB4.2E - Tilghman Island 11.7 9.9 8.9
CB4.2C - MD Mid Bay 11.2 10.4 10.8 7.6 2.7
CB4.2W - Plum Point 11.8 9.8 8.5
CB4.3W - Dares Beach 11.7 10.6 8
CB4.3E - Mouth of Choptank River 10.8 7.6 2.4
CB4.3C - Dares Beach 11.2 10.5 10.9 7.6 3.2
CB4.4 - Cove Point 11.3 11 9.7 7.9 4.4
CB5.1W - Mouth of Patuxent River 12.3 10.7 11.8 10.1 9.6
CB5.1 - Cedar Point 11.3 10.9 9.6 8 4.8
CB5.2 - Point No Point 11.4 11.1 9.5 8.5 5.1
CB5.3 - Smith Point 11.2 11.5 9.8 8.8 7

Bottom Dissolved Oxygen (mg/l)
0.0 - 0.2 (anoxia - kills most life)
0.2 - 2.0 (hypoxia - harms bottom organisms)
2.0 - 3.0 (stresses smaller fish and crabs)
3.0 - 5.0 (stresses larger fish)
5.0 - 10.0 (healthy)
10.0 + (could indicate an algal bloom in summer)
No Data

Dissolved oxygen (DO) in the water sustains life for Bay organisms. Nutrients, such as nitrogen and phosphorus, from agricultural, sewer/septic and urban sources can fuel algal blooms that can starve the water of DO. DO levels above 5 mg/l are normally sufficient to support most life.

More info on: "Our Monitoring Explained"