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LakeQuality

Old Mount Olive Reservoir

NR
Not yet rated
35 acres

Old Mount Olive Reservoir in Macoupin County, Illinois is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 35 acres.

Area
35 acres

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Why Old Mount Olive Reservoir has no grade

We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Old Mount Olive Reservoir, no water-quality sampling on record for this lake.

Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.

Sampling is run by Illinois EPA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.

Old Mount Olive Reservoir is a 35-acre lake in Macoupin County, Illinois.

Source: EPA Water Quality Portal sampling records, Illinois EPA, last sampled recent years. Grade methodology: LakeQuality methodology.

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Swimming Safety

Not rated

Elevated nutrients

Not rated for swimming — there is not enough monitoring data to judge this lake

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Water quality measurements for Old Mount Olive Reservoir

These readings exist but are not enough for an A–F grade — see why.

No clarity data. Trophic State Index: undefined.

MetricValueGrade
Water Clarity (Secchi Depth)No recent samples
PhosphorusNo recent samples
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)

Where to stay near Old Mount Olive Reservoir

Compare lakeside cabins, hotels, and vacation rentals near Old Mount Olive Reservoir in Macoupin County, Illinois — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.

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Lake Details

CharacteristicValue
Surface Area35 acres

No bathymetric survey has been published for Old Mount Olive Reservoir, so its depth is not documented here.

Fishing Old Mount Olive Reservoir

Nearby Lakes in Macoupin County

Frequently asked questions about Old Mount Olive Reservoir

Where is Old Mount Olive Reservoir?

Old Mount Olive Reservoir is a lake in Macoupin County, Illinois. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.

What is the water quality grade for Old Mount Olive Reservoir?

Old Mount Olive Reservoir in Macoupin County, Illinois is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 35 acres.

Is Old Mount Olive Reservoir safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Old Mount Olive Reservoir is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.

Where this data comes from

Measurements for Old Mount Olive Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.