Iatt Lake Southwest of Fairfield
Grant Parish County, Louisiana7,100 acresView 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 Iatt Lake Southwest of Fairfield. Here is what has been measured.
- Hypereutrophic
- Public access
- Limited data
Iatt Lake Southwest of Fairfield in Grant Parish County, Louisiana has water-quality measurements published by LDEQ, shown here as reported. Phosphorus: 100 µg/L. Surface area: 7100 acres.
Iatt Lake Southwest of Fairfield is a 7,100-acre highly nutrient-loaded hypereutrophic lake in Grant Parish County, Louisiana. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 1 other monitored lakes in Grant Parish County, Iatt Lake Southwest of Fairfield ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2022-09-07. Methodology: how these readings are compared.
What Iatt Lake Southwest of Fairfield is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Big water7,100 acres
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. Check local advisories before you swim.
Whether Iatt Lake Southwest of Fairfield 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 Iatt Lake Southwest of Fairfield
These are the measurements LDEQ publishes for Iatt Lake Southwest of Fairfield, 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 100 µg/L. TSI 71.
| 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 | 100µg/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. | 71 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Iatt Lake Southwest of Fairfield
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
7,100 acres
Public access
Yes
Listed by LDEQ
No bathymetric survey has been published for Iatt Lake Southwest of Fairfield, so its depth is not documented here.
Recreation & Access
- Dam LandingPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Iatt Lake Southwest of Fairfield
Compare lakeside cabins, hotels, and vacation rentals near Iatt Lake Southwest of Fairfield in Grant 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 Iatt Lake Southwest of Fairfield are listed below.
Top-rated places to stay near Iatt Lake Southwest of Fairfield
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Fishing Iatt Lake Southwest of Fairfield
Reservoir Info (USACE NID)
Iatt Lake Southwest of Fairfield is a man-made reservoir impounded by the Iatt Lake Dam (completed 1956), built primarily for recreation on the Bayou Rigolette; earth-type dam, 36 ft tall and 5,310 ft long.
- Surface area
- 7,100 ac
- Normal storage
- 31,000 ac-ft
- Max storage
- 167,000 ac-ft
- Drainage area
- 242 sq mi
- Hazard class
- High
- Owner
- State of Louisiana
Source: USACE National Inventory of Dams, NID ID LA00018 · Operator website · Matched by proximity (0.43 km)
Nearby Lakes in Grant Parish County
Frequently asked questions about Iatt Lake Southwest of Fairfield
Where is Iatt Lake Southwest of Fairfield?
- Iatt Lake Southwest of Fairfield is in Grant 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 Iatt Lake Southwest of Fairfield?
- Iatt Lake Southwest of Fairfield in Grant Parish County, Louisiana has water-quality measurements published by LDEQ, shown here as reported. Phosphorus: 100 µg/L. Surface area: 7100 acres.
Is Iatt Lake Southwest of Fairfield safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Are there boat ramps on Iatt Lake Southwest of Fairfield?
- Iatt Lake Southwest of Fairfield has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Dam Landing. Public access is listed as yes.
Can I fish at Iatt Lake Southwest of Fairfield?
- Iatt Lake Southwest of Fairfield has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Louisiana's fish and wildlife agency, so check its current regulations before you go.
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Hypereutrophic Lakes in Louisiana
Where this data comes from
21 measurements from 1 monitoring station, 2021–2022. Retrieved from the EPA Water Quality Portal on 2026-08-21.
Collected and reported by
- LDEQ/Water Planning and Assessment (Louisiana)
LADEQWPD_WQX21 samples · 2021–2022
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
Named boat-access points from the USGS National Boat Ramps inventory