Seaman Reservoir
Larimer County, Colorado125 acresView mapDirections
No nutrient or algae sampling on record from Colorado WQCD for this lake.
- Impaired · Metals (other than mercury)
Seaman Reservoir in Larimer County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Surface area: 125 acres.
Seaman Reservoir is a 125-acre lake in Larimer County, Colorado.
Source: EPA Water Quality Portal sampling records, CDPHE. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Seaman Reservoir is listed impaired under Clean Water Act §303(d) (IR 5) for metals (other than mercury), oxygen depletion (low DO). Check local advisories before you swim.
Whether Seaman Reservoir is safe to swim in today is a call for the Water Quality Control Division of the Colorado Department of Public Health and Environment and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Seaman Reservoir
These are the measurements Colorado WQCD publishes for Seaman 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 Seaman Reservoir
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
125 acres
Shoreline
3.9 mi
No bathymetric survey has been published for Seaman Reservoir, so its depth is not documented here.
Stays via Stay22
Stays near Seaman Reservoir
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Fishing Seaman Reservoir
EPA Impairment Status
Seaman Reservoir is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Drinking water, Aquatic life.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit COSPCP20_B · Official waterbody report
Nearby Lakes in Larimer County
Frequently asked questions about Seaman Reservoir
Where is Seaman Reservoir?
- Seaman Reservoir is a lake in Larimer County, Colorado. Its water-quality measurements are published by Colorado WQCD and shown on this page as reported.
What is the water quality of Seaman Reservoir?
- Seaman Reservoir in Larimer County, Colorado has water-quality measurements published by Colorado WQCD, shown here as reported. Surface area: 125 acres.
Is Seaman Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Seaman Reservoir is listed impaired under Clean Water Act §303(d) (IR 5) for metals (other than mercury), oxygen depletion (low DO). Check local advisories before you swim.
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Where this data comes from
Measurements for Seaman 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