Water Quality Monitoring

Click here to see CBA's Water Quality stations.




The Choctawhatchee Basin Alliance (CBA) of Northwest Florida State College works with the University of Florida's Florida LAKEWATCH program to conduct monthly water quality monitoring of more than 140 stations in throughout the watershed, including Choctawhatchee Bay, Choctawhatchee River, and Walton County's coastal dune lakes. This collaboration allows us to establish baseline water quality data for our local water resources, which can then be used to help identify areas of poor water conditions, determine the causes of water degradation, and identify solutions to improve water quality throughout the basin. CBA’s data are uploaded to the State’s STOrage and RETrival data base (STORET) and are available to the public. The data that CBA collects is public knowledge and the data is available upon request. Currently, CBA is working on creating an interactive map that will display data trends within the watershed. The data collected is used by local municipalities as well as state and federal agencies to manage and regulate our waters.

Our water quality monitoring program is conducted almost wholly by a large group of dedicated citizen scientist volunteers. In the field, a surface- and bottom-level reading of the following parameters are recorded at each station: temperature, dissolved oxygen, pH, salinity, oxygen saturation, and water clarity. In addition, two water samples are collected which are analyzed by the Florida LAKEWATCH program for nutrient concentration (total nitrogen and total phosphorus) and algae content (chlorophyll).

Check out this Video from our friends at the Good Samaritan Institute about CBA's Citizen Scientists and water quality monitoring program along the Coastal Dune Lakes!

Recruitment and Training of Volunteers

The Choctawhatchee Basin Alliance training goal is to maintain qualified citizen monitors over the 130+ sampling sites located within the Choctawhatchee Bay, Choctawhatchee River, all the coastal dune lakes in Walton County, and even in the Gulf of Mexico, just off shore in Okaloosa and Walton County. Click here to view a map of CBA's current sampling stations. CBA staff conducts approximately 15 training sessions per year to maintain almost 34 active volunteers in the CBA water quality monitoring program. If you are interested in participating in this program, please email Brandy, our Monitoring Coordinator, your contact information (

Citizen scientist volunteers are trained by professional staff from CBA on the proper procedures for collecting surface (1.5 feet) water samples and determining water clarity as measured by a Secchi disc. Volunteers are also trained to use a Quanta Hydrolab Water Quality Monitoring System provided by CBA to record surface and bottom measurements of temperature (°F), dissolved oxygen (mg/L), pH, salinity (ppt), dissolved oxygen saturation (%), and turbidity (NTU). Citizen volunteers are usually instructed on their waterbody during a two to four hour training session, which includes the selection and/or identification of sampling stations and water sampling procedures for both the Florida LAKEWACH Program and the CBA hydrolab. After receiving instructions, citizens are expected to sample their water body once each month. Volunteers are required to contact CBA monthly to schedule their sampling date to ensure availability of the Hydrolab Quanta Water Quality Monitoring System and to coordinate the pick-up and return of sampling equipment. When a volunteer is unable to sample, CBA staff tries to collect water samples in their place. All volunteers are given sampling materials and booklets describing the water quality sampling procedures for future reference.


Field and Laboratory Procedures

On each sampling date, citizen volunteers use their own boats or dedicated CBA watercraft to collect surface and bottom readings as well as surface water samples from three to ten open-water locations. Sometimes large water bodies are split into smaller areas, and each smaller area of the large water body is then sampled monthly by different citizen volunteers. For example, Western Lake in Walton County has a surface area of 220 acres (Shafer et al. 1986). Western Lake was split into three smaller areas for sampling by volunteers: Western, Western Northeast, and Grayton. Western’s three sampling stations are located south of the 30A bridge, Western Northeast’s three sampling locations are located on the north side of the 30A bridge, and Grayton’s three sampling stations are located in the west basin around the Grayton subdivision.

CBA water monitoring efforts by citizen volunteers are a part of the statewide effort of the Florida LAKEWATCH Program. The Florida LAKEWATCH Program is run through the University of Florida’s Institute of Food and Agricultural Sciences’ Department of Fisheries. It is the largest citizen volunteer monitoring program in the nation. Surface samples for total phosphorus (µg/L), total nitrogen (µg/L), color (Pt-CO Units) and specific conductance (µS/cm @25°C) are collected at lake sampling stations in 250-ml, acid-cleaned, triple-rinsed Nalgene bottles and at bay sampling stations in 500-ml, acid-cleaned, triple-rinsed Nalgene bottles. Citizens also measure water clarity at each sampling location with a Secchi disc and collect additional surface water at each location in tap-water rinsed plastic jugs. Volunteers also use a Hydrolab Quanta Water Quality Monitoring System provided by CBA to record the following parameters at the surface and bottom of each sampling station: temperature (°F), dissolved oxygen (mg/L), pH, salinity (ppt), dissolved oxygen saturation (%), and turbidity (NTU).

Upon returning to their residences, volunteers place the 250-ml or 500-ml Nalgene bottles in a freezer. To estimate the concentration of planktonic algae at each sampling station, volunteers filter a measured volume of water taken from the plastic jugs through a Gelman 47mm Type A-E glass fiber filter. Filters are then stored over silica gel desiccant and frozen.

Water samples and the glass fiber filters are stored frozen at the homes of the citizen volunteers or at one of two LAKEWATCH collection centers located in Okaloosa and Walton Counties for one to four months. All frozen samples along with Secchi disc information are then delivered by Florida LAKEWATCH staff to the Department of Fisheries and Aquatic Science's water quality laboratory. All samples and filters are analyzed for total phosphorus, total nitrogen and chlorophyll concentrations monthly. Color is run quarterly on composite water samples for all lakes. Color and specific conductance (µS/cm @ 25°C) are run quarterly on bay stations.

At the laboratory, total phosphorus concentrations (µg/L) are determined using the procedures of Murphy and Riley (1962) with a persulfate digestion (Menzel and Corwin 1965). Total nitrogen concentrations (µg/L) for all lake samples are determined by oxidizing water samples with persulfate and determining nitrate-nitrogen with second derivative spectroscopy (D’Elia et al. 1977; Simal et al. 1985; Wollin 1987). A total nitrogen equivalency study of nitrogen in surface waters demonstrated that this method is a suitable substitute for the standard USEPA method involving the sum of nitrate-nitrogen and Kjeldahl-nitrogen as measured with an automated analyzer (Sylvia S. Labie, Administrator Florida Department of Environmental Regulation Quality Assurance Section, 1991). Total nitrogen concentrations (µg/L) for bay samples are determined by oxidizing water samples with persulfate and determining nitrate-nitrogen with an autoanalyzer, (Method 4500-NO3-F ; APHA 1992). Chlorophyll concentrations (µg/L) are determined spectrophotometrically (Method 10200 H; APHA 1992) following pigment extraction with ethanol (Sartory and Grobbelaar 1984). Specific conductance (µS/cm @ 25°C) is measured using a Yellow Springs Instrument Model 35 conductance meter. Color (Pt-Co Units) is determined by spectroscopy (Bowling et al. 1986).