Grand Lake Southwest of Gueydan
Cameron Parish County, LouisianaView mapDirections
This is the name LDEQ records for this water. It can describe one sampling location rather than the water as a whole.
LDEQ publishes the water-quality measurements for Grand Lake Southwest of Gueydan. Here is what has been measured.
- Hypereutrophic
- Impaired · Pesticides
- Limited data
Grand Lake Southwest of Gueydan in Cameron Parish County, Louisiana has water-quality measurements published by LDEQ, shown here as reported. Phosphorus: 140 µg/L.
Grand Lake Southwest of Gueydan is a highly nutrient-loaded hypereutrophic lake in Cameron Parish County, Louisiana.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2023-10-03. Methodology: how these readings are compared.
Swimming conditions
Readings onlyLimited data
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. Grand Lake Southwest of Gueydan is listed impaired under Clean Water Act §303(d) (IR 4A) for pesticides, turbidity. Check local advisories before you swim.
Whether Grand Lake Southwest of Gueydan is safe to swim in today is a call for the Louisiana Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Grand Lake Southwest of Gueydan
These are the measurements LDEQ publishes for Grand Lake Southwest of Gueydan, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Phosphorus 140 µg/L. TSI 75.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 140µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 75 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Grand Lake Southwest of Gueydan
Answers come straight from the public measurements and survey records on this page.
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Stays near Grand Lake Southwest of Gueydan
Compare lakeside cabins, hotels, and vacation rentals near Grand Lake Southwest of Gueydan in Cameron Parish County, Louisiana — 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 Grand Lake Southwest of Gueydan are listed below.
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Fishing Grand Lake Southwest of Gueydan
EPA Impairment Status
Grand Lake Southwest of Gueydan 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: Aquatic life.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit LA050701_00 · Official waterbody report
Nearby Lakes in Cameron Parish County
Frequently asked questions about Grand Lake Southwest of Gueydan
Where is Grand Lake Southwest of Gueydan?
- Grand Lake Southwest of Gueydan is in Cameron Parish County, Louisiana. This is the name LDEQ records for this water. It can describe one sampling location rather than the water as a whole. Its water-quality measurements are published by LDEQ and shown on this page as reported.
What is the water quality of Grand Lake Southwest of Gueydan?
- Grand Lake Southwest of Gueydan in Cameron Parish County, Louisiana has water-quality measurements published by LDEQ, shown here as reported. Phosphorus: 140 µg/L.
Is Grand Lake Southwest of Gueydan safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Grand Lake Southwest of Gueydan is listed impaired under Clean Water Act §303(d) (IR 4A) for pesticides, turbidity. Check local advisories before you swim.
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Where this data comes from
20 measurements from 1 monitoring station, 2022–2023. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- LDEQ/Water Planning and Assessment (Louisiana)
LADEQWPD_WQX20 samples · 2022–2023
Analytical methods
- Total Phosphorus After Block Digestion
- 2130 B ~ Nephelometric Method
Monitoring station identifiers (1)
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.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database