The following data are summarized as seasonal average values for lake and river sampling locations located within the watershed. While these data are useful to serve as a general picture of watershed health, these data must be viewed with caution because these samples have been taken from ecologically different water resources.

Rivers:

Samples from most rivers located in this watershed are averaged as part of these data summaries.

Season	Total Nitrogen	Nitrate (NO3)	Total Phosphorus	Orthophosphate	Number of Sample Stations	Number of Samples
JAN-MAR 2024	1,470 ug/l		872 ug/l	0.47 mg/l	11	13
OCT-DEC 2023	1,498 ug/l		756 ug/l	0.55 mg/l	12	16
JUL-SEP 2023	1,274 ug/l		1,348 ug/l	1.05 mg/l	6	8
APR-JUN 2023	1,480 ug/l		1,167 ug/l	0.67 mg/l	8	13
JAN-MAR 2023	1,621 ug/l		751 ug/l	0.53 mg/l	13	17
OCT-DEC 2022	1,569 ug/l		1,286 ug/l	0.95 mg/l	15	20
JUL-SEP 2022	1,506 ug/l		1,116 ug/l	0.86 mg/l	14	16
APR-JUN 2022	1,351 ug/l		1,191 ug/l	0.57 mg/l	15	21
JAN-MAR 2022	1,515 ug/l		770 ug/l	0.64 mg/l	14	19
Five Year Seasonal Graph	Graph		Graph	Graph
Five Year Graph of All Samples	Graph		Graph	Graph

Source(s): Quarterly Routine Water Monitoring, EPC Monthly Routine Water Monitoring, Hillsborough County Lake Assessments, EPC Water Quality Data, LAKEWATCH Volunteer Water Quality Monitoring, FDEP Historic Data from Legacy STORET, Polk County Parks & Natural Resources Division, FDEP Watershed Monitoring Section, IMC Agrico (Florida), SWFWMD Water Quality Sampling Data, FDEP Southwest Regional Operations Center, Stream Waterwatch Water Quality Data, Volunteer , USGS National Water Information System, FDEP Watershed Monitoring Section, Environmental Protection Commission of Hillsborough County, Polk County Natural Resources Division, Southwest Florida Water Management District, FDEP - Southwest Regional Operations Center

Lakes:

Samples from most lakes located in this watershed are averaged as part of these data summaries.

Season	Total Nitrogen	Nitrate (NO3)	Total Phosphorus	Orthophosphate	Number of Sample Stations	Number of Samples
JAN-MAR 2024	1,292 ug/l		336 ug/l		2	2
OCT-DEC 2023	1,124 ug/l		390 ug/l		2	2
JUL-SEP 2023	1,360 ug/l		551 ug/l		2	2
APR-JUN 2023	1,170 ug/l		540 ug/l		2	2
JAN-MAR 2023	1,060 ug/l		365 ug/l		2	2
OCT-DEC 2022	1,190 ug/l		683 ug/l		2	2
JUL-SEP 2022	1,273 ug/l		522 ug/l		2	2
APR-JUN 2022	1,214 ug/l		400 ug/l		2	2
JAN-MAR 2022	1,535 ug/l		374 ug/l		2	2
Five Year Seasonal Graph	Graph		Graph	Graph
Five Year Graph of All Samples	Graph		Graph	Graph

Source(s): LAKEWATCH Volunteer Water Quality Monitoring, Polk County Parks & Natural Resources Division, FDEP Watershed Monitoring Section, SWFWMD Water Quality Sampling Data, FDEP Southwest Regional Operations Center, SWFWMD Water Quality Monitoring Program Data, USGS National Water Information System, Florida LAKEWATCH, Polk County Natural Resources Division, FDEP - Southwest Regional Operations Center, FDEP - Watershed Assessment Section

Southwest Florida Water Management District calculates the Aquifer Resource Indicator (ARI) for their three groundwater regions each month. The ARI was created to provide the public with a gauge of groundwater levels in their area, so they can develop an understanding of the severity and cycles of drought and recovery. The three regions include: North (Citrus, Hernando, Lake, Levy, Marion, and Sumter counties), Central (Hillsborough, Pasco, Pinellas, and Polk counties), and South (Charlotte, DeSoto, Hardee, Highlands, Manatee, and Sarasota counties). Learn More about the Aquifer Resource Indicator >>

To determine the ARI for a region, each well is compared weekly to its respective low-normal value and the difference is calculated. The weekly differences are reduced to a monthly value for all monitoring wells within a region, and the resulting ARI value represents how far water levels in the aquifer must rise or fall to reach their respective low-normal values.

Source: SWFWMD Hydrologic Data Section Data

River	Flows Whole River Range	Flows Data by Segment	Levels Whole River Range	Levels Data By Segment
Alafia River - North Prong	In the past 30 days Average river flow is slower than it has been historically.	Flows Data Table and Graph	In the past 30 days Average water levels are higher than they have been historically.	Levels Data Table and Graph
Alafia River - South Prong	In the past 30 days Average river flow is slower than it has been historically.	Flows Data Table and Graph	In the past 30 days Average water levels are higher than they have been historically.	Levels Data Table and Graph
Thirtymile Creek	In the past 30 days NO DATA Recent river flow data is unavailable.	No data table or graph available	In the past 30 days Average water levels are higher than they have been historically.	Levels Data Table and Graph

Source(s): Not Available

Source(s): Not Available