Lag Lake
Volusia County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Lag Lake. Here is what has been measured.
- Eutrophic
- Impaired · Algal growth
Lag Lake in Volusia County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 2.3 ft visibility. Phosphorus: 43.1 µg/L.
Lag Lake is a productive, nutrient-rich eutrophic lake in Volusia County, Florida. Water clarity is declining over recent sampling years. Compared to the 29 other monitored lakes in Volusia County, Lag Lake ranks #19 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-01-22. Methodology: how these readings are compared.
Swimming conditions
Readings onlyRecreation use not supported
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. Lag Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for algal growth, mercury, nutrients (phosphorus, nitrogen), salinity / chlorides. Check local advisories before you swim.
Whether Lag Lake is safe to swim in today is a call for the Florida Department of Environmental Protection and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Lag Lake
These are the measurements Florida DEP publishes for Lag Lake, 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 43.1 µg/L. TSI 62.
| 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 | 43.1µg/L | Fair 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. | 62 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lag Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lag Lake typically sits around 73°F at the surface in October. Summer average is about 85°F. Usually warmest in Jun (about 85°F) and coldest in Dec (about 50°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (50°F) to its warmest (85°F).
Typical surface water temperature by month, from 218 field readings (2010–2025) via the EPA Water Quality Portal. See the full Lag Lake water temperature breakdown →
Stays via Stay22
Stays near Lag Lake
Compare lakeside cabins, hotels, and vacation rentals near Lag Lake in Volusia County, Florida — 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.
Top-rated places to stay near Lag Lake
Prices for Oct 16–18, 4 adults. Change dates on the map below.
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Fishing Lag Lake
Water Quality Trend: Stable
Based on 5 years of monitoring (2020–2024).
Water clarity
Worsening5 years
Phosphorus
Improving-9.28 µg/L/yr5 years
EPA Impairment Status
Lag Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Aquatic life, Fish consumption, Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit FL2893A · Official waterbody report
Nearby Lakes in Volusia County
Frequently asked questions about Lag Lake
Where is Lag Lake?
- Lag Lake is a lake in Volusia County, Florida. Its water-quality measurements are published by Florida DEP and shown on this page as reported.
What is the water quality of Lag Lake?
- Lag Lake in Volusia County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 2.3 ft visibility. Phosphorus: 43.1 µg/L.
Is Lag Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lag Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for algal growth, mercury, nutrients (phosphorus, nitrogen), salinity / chlorides. Check local advisories before you swim.
What is the water temperature of Lag Lake?
- Lag Lake typically sits around 73°F at the surface in October, from 218 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
Explore Lag Lake across LakeQuality
Planning a trip around Fort Matanzas?
Lag Lake is about 38 miles from Fort Matanzas National Monument. Crowds there swing hard by season, so the month you pick changes both how busy the park is and what lodging costs.
Best time to visit Fort Matanzas →More lakes in Florida
Other Lakes in Florida
Eutrophic Lakes in Florida
Where this data comes from
150 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- St. Johns River Water Management District
21FLSJWM_WQX150 samples · 2020–2025
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