Cyanobacteria advisory (harmful blue-green algae) reported, Mar 16, 2023
Advisory active · Florida Department of Environmental Protection (Algal Bloom Sampling)
Source: Florida Department of Environmental Protection (Algal Bloom Sampling) via Florida DEP Algal Bloom Sampling, blooms and toxins by site, record 39b23161-4753-48cc-9889-946358e62c9b, updated by the source Oct 26, 2026, 12:05 PM EDT, retrieved 2026-11-05 01:05 UTC · Read the original notice
Current status from this report
Discharge or advisory reported not linked to a mapped water: Official advisory in effect. Current rule period ends Nov 9, 2026, 11:05 AM EST. This is not a water-quality test.
Why this status: Discharge or advisory reported: official advisory.
Why we use this rule: An official advisory is listed. We show it while the authority keeps it in place; an old or missing update does not mean the advisory was lifted.
A report is not a test of the water. See how we assign statuses.
Read the original notice · Report an error
1. Where the advisory applies
Issued by: Florida Department of Environmental Protection (Algal Bloom Sampling). Place named: “Lake Howell - NW Shore”. Location: 28.64335, -81.31778; location source: given in the source record, accurate to about 10 metres.
2. Waters named in the notice
The notice names: “Lake Howell”. Not linked to a mapped water.
Map sources: water outlines and launches from OpenBoatLaunch and OpenStreetMap contributors (Open Database License); wastewater outlets from EPA and state records; downstream estimates by DirtyWaterWatch using U.S. Geological Survey maps and flow data. Base map: OpenFreeMap and OpenMapTiles.
When it happened and when it was reported
Event and notice times use Eastern Time (EST or EDT). Retrieval times use Coordinated Universal Time (UTC).
- Started
- Ended
- not reported
- Detail provided by the source
- Times known to the minute
- Reported to the source
- not given
- Published
- not given
- Source last updated
- Last retrieved by DirtyWaterWatch
What was reported
- Type
- Cyanobacteria (harmful blue-green algae) can make water unfit for contact; the issuing authority decides when its advisory ends.
- Status in the record
- Advisory active
- Material
- “algal bloom (Dominant taxon: Microcystis aeruginosa; Co-dominant taxa were: Microcystis aeruginosa and Microcystis wesenbergii; Co-dominant taxa were: Microcystis aeruginosa and Planktolyngbya limnetica; Co-dominant taxa were: Microcystis aeruginosa and Microcystis sp.; Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii; Dominant taxon: Planktolyngbya limnetica; mixed algae; no dominant species in sample; Co-dominant taxa were: Microcystis aeruginosa and Botryococcus braunii; Co-dominant taxa were: Raphidiopsis raciborskii and Planktolyngbya limnetica)”
Advice from Florida Department of Environmental Protection (Algal Bloom Sampling)
This report includes no advice. Check current local health notices.
- Advice period
- This report does not state a period. See the rule DirtyWaterWatch applies and its source.
- Basis
- not stated
Status history from this report
- Discharge or advisory reported a water not yet on the map: Official advisory in effect, Mar 16, 2023, 1:22 PM EDT to Nov 9, 2026, 11:05 AM EST (the end is scheduled: a new report can change it)
Source: DirtyWaterWatch calculations using this report and the published status rules. Updated 2026-11-05 01:25 UTC.
Source and versions
- Source
- Florida DEP Algal Bloom Sampling, blooms and toxins by site
- Source record number
- 39b23161-4753-48cc-9889-946358e62c9b
- Original notice
- Read the original notice
- Earlier version
- None: this is the first record
- Later versions
- None
Record details
| Record identifier | fl-dep-habs:39b23161-4753-48cc-9889-946358e62c9b |
|---|---|
| Source identifier | fl-dep-habs |
| Source record number | 39b23161-4753-48cc-9889-946358e62c9b |
| Earlier version | Not provided |
| Type | Cyanobacteria advisory (harmful blue-green algae) |
| Status in the report | Advisory active |
| Sewer operator identifier | Not provided |
| Sewer operator | Not provided |
| Federal wastewater discharge permit (NPDES) | Not provided |
| Outlet number | Not provided |
| Outlet name | Lake Howell - NW Shore |
| Water named in the report | Lake Howell |
| Linked waters | Not provided |
| How this report was linked to the water | not linked to a mapped water |
| Latitude | 28.643 |
| Longitude | -81.318 |
| Location source | given in the source record |
| Location accuracy, in metres | 10 |
| Started | Mar 16, 2023, 1:22 PM EDT (2023-03-16T13:22:00-04:00) |
| Ended | Not provided |
| Detail provided by the source | to the minute |
| Reported to the source | Not provided |
| Published | Not provided |
| Source last updated | Oct 26, 2026, 12:05 PM EDT (2026-10-26T12:05:00-04:00) |
| Last retrieved by DirtyWaterWatch | Nov 4, 2026, 8:05 PM EST (2026-11-05T01:05:45Z) |
| Material | algal bloom (Dominant taxon: Microcystis aeruginosa; Co-dominant taxa were: Microcystis aeruginosa and Microcystis wesenbergii; Co-dominant taxa were: Microcystis aeruginosa and Planktolyngbya limnetica; Co-dominant taxa were: Microcystis aeruginosa and Microcystis sp.; Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii; Dominant taxon: Planktolyngbya limnetica; mixed algae; no dominant species in sample; Co-dominant taxa were: Microcystis aeruginosa and Botryococcus braunii; Co-dominant taxa were: Raphidiopsis raciborskii and Planktolyngbya limnetica) |
| Volume, in gallons | Not provided |
| Volume as reported | Not provided |
| How volume was determined | not stated whether estimated or measured |
| Authority | Florida Department of Environmental Protection (Algal Bloom Sampling) |
| Advice | Not provided |
| Advice period, in hours | Not provided |
| Basis of the advice period | Not provided |
| Original notice | https://services1.arcgis.com/nRHtyn3uE1kyzoYc/arcgis/rest/services/AlgalBloom_Final_View/FeatureServer/0/query?where=globalid%3D%2739b23161-4753-48cc-9889-946358e62c9b%27&outFields=objectid,globalid,SampleDateTime,MonitoringGroupPublicFacing,County,esrignss_latitude,esrignss_longitude,BloomObserved,MeterReadingsOnly,SampleDepthDesc,AnalyzedBy,AlgalIDResult,ToxinPresent,Microcystin,OtherToxin,locationString,EditDate,CyanobacteriaDominant&f=json |
Original source data
{
"site": "Lake Howell - NW Shore",
"site_key": "lake howell nw shore",
"county": "Seminole",
"group": "CEROC",
"visits": [
{
"time": "2023-03-16T13:22:00-04:00",
"globalid": "39b23161-4753-48cc-9889-946358e62c9b",
"bloom_observed": "Yes",
"toxin_present": "No",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: not detected; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Microcystis aeruginosa",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:20:27.157000-05:00"
},
{
"time": "2024-05-23T11:21:00-04:00",
"globalid": "1a86520b-cd2c-44eb-9789-9fde0e1f6e80",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "1.8 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.68; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Microcystis wesenbergii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:27:09.600000-05:00"
},
{
"time": "2024-06-10T14:19:00-04:00",
"globalid": "90f8827a-131f-486d-9855-220853f610f2",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.57 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: 0.28 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Cylindrospermopsin: 0.69; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Microcystis wesenbergii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:27:35.292000-05:00"
},
{
"time": "2024-06-26T13:05:00-04:00",
"globalid": "5eca40a5-666e-44e5-bd09-cd0efe973899",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: 1.1; Cylindrospermopsin: 1.8; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Planktolyngbya limnetica",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:27:57.977000-05:00"
},
{
"time": "2024-07-10T14:44:00-04:00",
"globalid": "1f3e430b-3acd-4cf6-8f52-e0b379a94940",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.51 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 2.8; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Microcystis aeruginosa",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:28:14.357000-05:00"
},
{
"time": "2024-07-31T11:04:00-04:00",
"globalid": "ba2acc32-3319-403a-9a94-0c6dc268e5f2",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.22 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 1.9; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Microcystis wesenbergii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:28:46.575000-05:00"
},
{
"time": "2024-08-19T12:45:00-04:00",
"globalid": "5c891b2f-2129-4f1a-a3b7-076af4f07fa9",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.10 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 1.0; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Microcystis sp.",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:29:00.342000-05:00"
},
{
"time": "2024-09-09T10:48:00-04:00",
"globalid": "72eb50b3-29ae-4c5e-b322-dfce00785b44",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.37 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Microcystis aeruginosa",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:29:25.979000-05:00"
},
{
"time": "2024-09-30T10:42:00-04:00",
"globalid": "733d08ee-2193-4632-8f43-df5f721d3d62",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.15 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Microcystis aeruginosa",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:29:43.522000-05:00"
},
{
"time": "2024-10-23T12:00:00-04:00",
"globalid": "614aaab6-2bbd-475c-b936-91c38586fd72",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.12 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Microcystis aeruginosa",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:30:06.954000-05:00"
},
{
"time": "2024-11-12T10:19:00-05:00",
"globalid": "91f77de7-d212-4b45-89e4-3f3161274acd",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.13 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Microcystis aeruginosa",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:30:18.258000-05:00"
},
{
"time": "2024-12-02T10:32:00-05:00",
"globalid": "48b43e47-a735-46ce-88be-98372a076ad6",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.11 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:30:29.728000-05:00"
},
{
"time": "2025-01-02T12:30:00-05:00",
"globalid": "9445a0c0-453a-4ab2-8de1-fcfa6dcfee1d",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.11 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:30:42.675000-05:00"
},
{
"time": "2026-06-03T09:34:00-04:00",
"globalid": "df4564e0-d2ca-4312-863f-4a173f7361b6",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.92 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: 0.72 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Cylindrospermopsin: 0.68; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Planktolyngbya limnetica",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:36:53.239000-05:00"
},
{
"time": "2026-06-17T10:51:00-04:00",
"globalid": "50a40838-663c-47ef-a054-bcc18b2bd09d",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.26 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: 0.60 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Cylindrospermopsin: 1.0; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Dominant taxon: Planktolyngbya limnetica",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:37:03.241000-05:00"
},
{
"time": "2026-07-08T10:58:00-04:00",
"globalid": "e0aa3ae7-6162-4358-9839-07520f1063ae",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.57 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 1.2; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Planktolyngbya limnetica",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:37:22.386000-05:00"
},
{
"time": "2026-07-21T10:57:00-04:00",
"globalid": "c8a5937f-a5bd-484e-adc5-90de5515c7c3",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.38 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 1.0; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "mixed algae; no dominant species in sample",
"cyanobacteria_dominant": "No",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:37:33.001000-05:00"
},
{
"time": "2026-08-05T14:40:00-04:00",
"globalid": "0baae9b9-9fc9-43ba-8e4f-8296a832c627",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.28 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.96; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Botryococcus braunii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:37:46.942000-05:00"
},
{
"time": "2026-08-19T13:36:00-04:00",
"globalid": "bb540dea-49d8-4ca6-9399-a083cfca512e",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "0.12 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.)",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.67; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:38:00.443000-05:00"
},
{
"time": "2026-09-09T10:37:00-04:00",
"globalid": "02373243-5111-44c5-8d0a-cb03f003a079",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.65; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:38:20.303000-05:00"
},
{
"time": "2026-09-24T11:32:00-04:00",
"globalid": "9f0e2537-6a59-4f88-8644-8c73feed13f4",
"bloom_observed": "No",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.62; Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Raphidiopsis raciborskii and Planktolyngbya limnetica",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:38:31.753000-05:00"
},
{
"time": "2026-10-12T13:14:00-04:00",
"globalid": "b8717bc9-d966-43bb-92a0-7ea3e87fc3ce",
"bloom_observed": "Yes",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.32 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Microcystis aeruginosa and Raphidiopsis raciborskii",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:38:39.489000-05:00"
},
{
"time": "2026-10-26T12:05:00-04:00",
"globalid": "8461c910-269e-4783-a879-f7c6fe37f8ea",
"bloom_observed": "No",
"toxin_present": "Yes",
"microcystin": "not detected",
"other_toxins": "Anatoxin-a: not detected; Cylindrospermopsin: 0.21 I (I qualifier indicates that the reported value is between the laboratory method detection limit and the laboratory practical quantitation limit.); Nodularin-R: not detected; Saxitoxins: not detected",
"taxa": "Co-dominant taxa were: Raphidiopsis raciborskii and Planktolyngbya limnetica",
"cyanobacteria_dominant": "Yes",
"sample_depth": "SurfaceGrab",
"group": "CEROC",
"edited": "2026-11-04T02:38:49.018000-05:00"
}
],
"basis": "Florida DEP observed an algal bloom, or found an algal toxin, in a sample at this site. This is a sampling result, not a health advisory; the Florida Department of Health issues health alerts separately."
} Staff names, email addresses and phone numbers are removed from source data before it is stored.