Water Quality Monitoring Programs

Pinellas County monitors the water quality of creeks, lakes, bays and intracoastal waters through a variety of programs to ensure we’re successfully managing our watersheds and meeting regulatory program requirements.

Pinellas County has monitored the quality of surface waters (creeks, lakes, bays and intracoastal waters) since 1991. If a waterbody does not meet the State standards indicative of a healthy system, it is considered impaired, and actions are required to improve water quality. More detailed Pinellas County water monitoring data can be viewed through the Pinellas County WaterAtlas.

You can view more information about our monitoring sites and results on our Watershed Information page, or for more information on the county’s monitoring programs, email watershed@pinellas.gov.

Two Pinellas County employees monitor water quality in a local pond.

Monitoring Program Components

Ambient Water Quality Monitoring

Throughout the year, Pinellas County collects samples from various streams, lakes and coastal waters around the county. Samples are analyzed to measure pH, dissolved oxygen, conductivity and salinity, water temperature and nutrients. 

This data is submitted to the Florida Department of Environmental Protection (FDEP) periodically for Clean Water Act assessments. The FDEP website presents the current water quality status of waters throughout the state.

Pinellas County Environmental Management taking samples

Bay Benthic Monitoring

The bottom of a waterbody is known as the benthic zone, and it’s a critical habitat for plants and animals. The plants and animals that live in, on or near the bottom are known as “benthos.”

Pinellas County participates in a bay-wide monitoring program to assess the health of the benthic environment. The health of the benthos can be determined by what organisms are found there, as well as what chemicals, such as metals and nutrients, are stored in the sediments.

The county collects data about sediment grain-size, sediment toxicity, water chemistry, water clarity and benthic macroinvertebrates and produces a report on these results every few years. The most recent report indicates local benthic environments are in fair to good condition and appear to be improving over time.

A Pinellas County employee checks the water quality of a local creek.

Biological Monitoring Program

Pinellas County’s biological monitoring program evaluates our freshwater streams, canals and lakes to ensure they are healthy, with a well-balanced population of fish and wildlife.

The FDEP has established methods to determine the health of an ecosystem.

This includes monitoring flowing waters (streams, canals, ditches) for levels of macroinvertebrates, algae and aquatic plants, as well as important attributes of available habitat. The county also monitors lakes for native, invasive and sensitive species.

View Pinellas County’s watershed summaries for local biological monitoring assessment results.

Pinellas County Environmental Management taking samples

Phytoplankton Monitoring Program

Phytoplankton are microscopic organisms that live in watery environments. Under certain conditions, phytoplankton populations can grow explosively, creating a “bloom” which can potentially have adverse effects. 

Pinellas County monitors phytoplankton in Lake Seminole and Lake Tarpon on a regular basis, and marine waters are monitored regularly during the wet season. The County also collects samples for analysis in response to potential blooms, as indicated by a visible color or the presence of dead organisms in the water.

Why monitor phytoplankton?

  • The relative abundance of phytoplankton species in an aquatic system can give an indication of general water quality conditions.
  • Phytoplankton are particularly sensitive to changes in nutrients, water clarity and other water quality parameters due to a short life cycle.
  • Some phytoplankton may impact human health as well as the health of aquatic organisms.

Harmful algal blooms (HABs) are tracked by the state and can be viewed on the FDEP Algal Bloom Sampling Status dashboard. You can also report a suspected HAB on this site. Red Tide is an example of a phytoplankton bloom that has impacted Pinellas County and surrounding areas recently. Learn more about this type of algal bloom on the county’s Red Tide information web page.

green algae in a pond

Seagrass Monitoring

Seagrass is an important coastal resource ecologically, recreationally and commercially. Seagrasses can reduce shoreline erosion and help improve water quality by trapping suspended sediments.

Pinellas County participates in a regional, multi-governmental seagrass monitoring program developed by the Tampa Bay Estuary Program (TBEP). The program was designed to characterize the general health and condition of seagrass meadows around the Tampa Bay area.

Historic seagrass acreage estimates for Tampa Bay from  1950 to 2018, showing 40,000 acres in 1950 then a drop to 20,000 acres in 1984. Acreage increases steadily over time until the total is back to 40,000 in 2018.

Pinellas County monitors seagrass in Tampa Bay, Boca Ciega Bay, Clearwater Harbor, and St. Joseph Sound. Results are summarized every two years, after compiling annual field data. The acreage of seagrass in Tampa Bay has increased significantly in recent years and is reaching targets set in the Tampa Bay Estuary Program’s Comprehensive Management Plan for Tampa Bay.