Toisnot Reservoir
Wilson County, North CarolinaView mapDirections
NC DEQ publishes the water-quality measurements for Toisnot Reservoir. Here is what has been measured.
- Eutrophic
Toisnot Reservoir in Wilson County, North Carolina has water-quality measurements published by NC DEQ, shown here as reported. Water clarity: 2.3 ft visibility. Phosphorus: 90 µg/L. Chlorophyll-a (algae): 18 µg/L.
Toisnot Reservoir is a productive, nutrient-rich eutrophic lake in Wilson County, North Carolina. Overall water quality is declining over recent sampling years. Compared to the 3 other monitored lakes in Wilson County, Toisnot Reservoir ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, NCDEQ, last sampled 2025-09-10. Methodology: how these readings are compared.
Swimming conditions
Readings onlyAlgae risk
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Toisnot Reservoir is safe to swim in today is a call for the North Carolina Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Toisnot Reservoir
These are the measurements NC DEQ publishes for Toisnot Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 2.3 ft of visibility. Phosphorus 90 µg/L. Chlorophyll-a 18 µg/L. TSI 64.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2.3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 90µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 18µg/L | Fair GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 64 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
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Stays via Stay22
Stays near Toisnot Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Toisnot Reservoir in Wilson County, North Carolina — 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. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Toisnot Reservoir are listed below.
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Fishing Toisnot Reservoir
Water quality readings over time
2 seasons of samples on record (2020–2025). Calling a direction takes at least 4 years of the same measurement.
Phosphorus
Stable-1 µg/L/yr2 years
Chlorophyll-a
Worsening+4.28 µg/L/yr2 years
Nearby Lakes in Wilson County
Frequently asked questions about Toisnot Reservoir
Where is Toisnot Reservoir?
- Toisnot Reservoir is a lake in Wilson County, North Carolina. Its water-quality measurements are published by NC DEQ and shown on this page as reported.
What is the water quality of Toisnot Reservoir?
- Toisnot Reservoir in Wilson County, North Carolina has water-quality measurements published by NC DEQ, shown here as reported. Water clarity: 2.3 ft visibility. Phosphorus: 90 µg/L. Chlorophyll-a (algae): 18 µg/L.
Is Toisnot Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Explore Toisnot Reservoir across LakeQuality
More lakes in North Carolina
Other Lakes in North Carolina
Eutrophic Lakes in North Carolina
Where this data comes from
53 measurements from 2 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- North Carolina Dept of Environmental Quality NCDEQ-DWR WQX
21NC03WQ53 samples · 2020–2025
Analytical methods
- WSSSOP
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
- 2130 B ~ Nephelometric Method
Monitoring station identifiers (2)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.