San Diego Water Quality Monitoring

Dinoflagellates emitting bioluminescence make us happy.

It means San Diego’s water does not have harmful levels of toxic chemicals that can harm plants, fish and bugs. And it’s one of the tests we conduct during our monthly water quality monitoring events.

Coastkeeper has monitored San Diego’s waterbodies since 2000. We use the data collected by our volunteers to identify polluted waters and reduce sources of pollution. San Diego’s local government agencies have limited resources and they monitor infrequently, providing only a snapshot of water quality. Data collected by Coastkeeper volunteers increases the amount available so regulators can assess more comprehensive water resources data to make more effective decisions on how to reduce sources of pollution.

Coastkeeper staff and its crew of trained volunteers (we train more than 450 volunteers each year) currently collect and analyze water samples that are analyzed for ambient measurements, basic water chemistry, bacteria,and  toxicity from nine out of 11 watersheds in San Diego County on a monthly basis. To ensure that our data meets the highest quality standards possible, Coastkeeper follows a rigorous quality assurance and control plan and standard operating procedures that have been approved by our state regulatory agencies.

To our knowledge, we are the largest volunteer-based water quality monitoring program in the state. Through this program, we create community involvement and stewardship by educating the public on the importance of good water quality in our coastal and inland waters. It adds the scientific data component to Coastkeeper's work. We are tremendously grateful to the volunteers and partners who share our passion for keeping our waters clean and healthy.

Please keep reading about our Water Quality Monitoring data or skip to:

• Uses for San Diego Water Quality Data

• San Diego Volunteers and Water Quality Monitoring

• San Diego Water Monitoring Consortium Partners

San Diego Water Quality Monitoring Data

We collect scientifically sound data backed by state-approved quality control standards. We test:

• Ambient Measurements

pH: We measure whether water is acidic or basic.

Oxygen: Organisms need enough oxygen to survive and thrive. We determine how much oxygen is dissolved in the water.

Conductivity: Conductivity is the electrical charge between non-organic solids in the water.

Temperature: Plants and animals have a normal range of water temperatures above which it becomes too stressful for them.

• Water Chemistry

Nitrates (NO₃) – We test for dissolved levels of nitrates, which is one form of nitrogen found in the environment. Although nitrates are an essential plant nutrient, they can cause significant water quality problems when levels are too high. Excessive levels of nitrates in waterways can cause problems like hypoxia (very low levels of oxygen in the water) and at very high levels can be toxic to animals. Some typical sources of excessive nitrates include fertilizer runoff from residential, agricultural or recreational areas like golf courses.

Phosphates (PO₄) - We test also for dissolved levels of phosphates, which is one form of its parent element, phosphorus, and is an essential plant nutrient. However, phosphorus is often in short supply in freshwater ecosystems, so small additions can lead to big changes in our local waterways. Too much phosphorus can cause excessive plant and algae growth and can lead to low levels of oxygen. Sources of phosphates are often present in detergents and other cleaners, runoff from fertilized lawns and agricultural fields, discharges from wastewater treatment plants and failing septic systems.

• Microbiology

Bacteria - We test water sample for bacteria levels that indicate the presence of waste from humans, wild animals, or domestic animals. We measure total coliform, Escherichia coli and Enterococci.

• Toxicity

We currently work with Assure Controls to assess the potential toxicity of our watersheds. We rapidly asses all sites each month for toxic events, using marine plankton (dinoflagellates) as a bioindicator.

As part of their normal life cycle, dinoflagellates emit light (bioluminescence). The amount of light that a population of dinoflagellates can emit will be less when exposed to biologically harmful levels of chemicals. We use Assure Controls small benchtop instrument to measure the light output of the organism after they have been exposed to water collected from creeks and lagoons. The availability of this test has made toxicity detection an affordable and achievable technique for Coastkeeper, providing the capability to confirm or update existing information and perform critical contaminant screening of water bodies.

Click on the map to see what our Water Quality Monitoring program finds in your local waters.

Uses for San Diego Water Quality Data (return to top)

After our volunteers have completed the laboratory analyses of the water samples, we check the data to ensure that it met our quality assurance standards. We post the approved data to our Watershed Monitoring Website so that our volunteers and members of the public can see the trends in the health of San Diego’s watersheds.

In addition, Coastkeeper submits the data to the State Water Resource Control Board (SWRCB), the state agency in charge of protecting the water quality in California. Every two years, the SWRCB must determine a list of water bodies that do not meet state mandated water quality standards. Federal law requires that water bodies included on this list of impaired waters or 303(d) list must also have a pollution budget and clean-up plan created to restore it, which is called a TMDL - the Total Maximum Daily Load.

This process can take a very long time; and we are less patient. In order to facilitate the identification and elimination of sources of water pollution, we also share our data with local stormwater pollution prevention agencies--the "police" who enforce water quality regulations.

San Diego Volunteers and Water Quality Monitoring (return to top)

Coastkeeper’s Watershed Monitoring Program creates a pathway for residents to get involved and learn the science tools they need to understand their watersheds and directly influence local resource management.

Once a month, the Coastkeeper offices turn into a training center. The monitoring event starts when volunteers come into the office, get coffee and breakfast and begin training. Coastkeeper staff teach new volunteers about the program, what will be monitored and why. Then the hands-on training begins. New volunteers are shown how to properly collect water samples from Coastkeeper’s demo watershed (the water fountain in our courtyard).

We then pair new volunteers with returning volunteers to create site teams, each with a Watershed Captain. Watershed Captains are local residents that have deep connections to certain waterbodies and “adopt” them – they frequently visit their watersheds and act as vigilant observers of what happens regularly and notice changes when they occur.

While in the field, these site teams will use sampling poles, bottles and meters to collect and analyze water. Additional water is collected for other measurements that cannot be done in the field. At the end of the day, site teams return the samples to the Coastkeeper lab for analysis. Another smaller group of volunteers will then analyze the water samples for the more complex laboratory analysis.

The data collected by these volunteers is a powerful tool – it will fill in the gaps created by the limited agency resources. This information can then be used to help protect sensitive ecosystems, identify and abate pollution sources, track the effectiveness of pollution prevention plans, and prevent further degradation of our precious water resources.

San Diego Water Monitoring Consortium Partners (return to top)