Connecticut River Reservoir
Grafton County, New Hampshire541 acresView mapDirections
No nutrient or algae sampling on record from NHDES for this lake.
- Impaired · Mercury
Connecticut River Reservoir in Grafton County, New Hampshire has water-quality measurements published by NHDES, shown here as reported. Surface area: 541 acres.
Connecticut River Reservoir is a 541-acre lake in Grafton County, New Hampshire.
Source: EPA Water Quality Portal sampling records, your state environmental agency. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Connecticut River Reservoir is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Connecticut River Reservoir is safe to swim in today is a call for the New Hampshire Department of Environmental Services and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Connecticut River Reservoir
These are the measurements NHDES publishes for Connecticut River Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. TSI undefined.
Ask about Connecticut River Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
541 acres
No bathymetric survey has been published for Connecticut River Reservoir, so its depth is not documented here.
Stays via Stay22
Stays near Connecticut River Reservoir
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Fishing Connecticut River Reservoir
EPA Impairment Status
Connecticut River Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit NHIMP801030203-01 · Official waterbody report
Nearby Lakes in Grafton County
Frequently asked questions about Connecticut River Reservoir
Where is Connecticut River Reservoir?
- Connecticut River Reservoir is a lake in Grafton County, New Hampshire. Its water-quality measurements are published by NHDES and shown on this page as reported.
What is the water quality of Connecticut River Reservoir?
- Connecticut River Reservoir in Grafton County, New Hampshire has water-quality measurements published by NHDES, shown here as reported. Surface area: 541 acres.
Is Connecticut River Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Connecticut River Reservoir is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
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Where this data comes from
Measurements for Connecticut River Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database