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 2025	697 ug/l		77 ug/l	0.06 mg/l	3	3
OCT-DEC 2024	1,031 ug/l		173 ug/l	0.12 mg/l	7	13
JUL-SEP 2024	1,115 ug/l		227 ug/l	0.18 mg/l	8	15
APR-JUN 2024	665 ug/l		143 ug/l	0.11 mg/l	7	13
JAN-MAR 2024	839 ug/l		127 ug/l	0.06 mg/l	10	16
OCT-DEC 2023	862 ug/l		149 ug/l	0.11 mg/l	9	17
JUL-SEP 2023	784 ug/l		183 ug/l	0.15 mg/l	5	7
APR-JUN 2023	915 ug/l		202 ug/l	0.13 mg/l	8	14
JAN-MAR 2023	760 ug/l		197 ug/l	0.13 mg/l	8	12
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, EPC Water Quality data gathered from reports, LAKEWATCH Volunteer Water Quality Monitoring, FDEP Historic Data from Legacy STORET, FDEP Watershed Monitoring Section, 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, 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
Five Year Seasonal Graph
Five Year Graph of All Samples

Source(s): LAKEWATCH Volunteer Water Quality Monitoring

• Water Quality Sampling Locations - View a map showing the point locations of water quality monitoring stations which collect data being presented on the Water Atlas.

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
Bullfrog Creek	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
Little Manatee River	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 lower than they have been historically.	Levels Data Table and Graph

Source(s): Not Available

Source(s): Not Available